633CSi Turbo - Not a Callaway or an E24 Anymore

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Re: 633CSi Callaway Turbo Car

Post by tschultz »

the last post was so many words, I tried to get a bunch of photos for this update:

With the head out to be reworked, I spent some time cleaning up the block. For some reason, there was a lot of build up on the deck, but going slowly I used a razor blade to get it all smooth to the touch.
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Considering the suggestions for these on this board and a few other individuals, I decided to send the manifold off to be ceramic coated by a shop here in Denver since I was waiting on the head anyway. Once I got it back, I felt silly because I realized I should have also done the turbine housing.
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Here is the TCD manifold with gaskets-- to show what I was writing about earlier.
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And the Callaway manifold for comparison. It is slightly lighter than the TCD, but overall seems like poor flow path design.
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My spare head that I thought had a good cam ended up being scored due to somebody who tightened down the banjo bolts and didn't replace the crush washers. The rebuilder didn't want to reuse it.
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So I did some research on cams. Below is a great comparison via Devinder. The cam profile detail isn't easy to find:

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The B35 cam was the best choice for bang for the buck for a replacement. The head back from the shop:
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I also went with ARP head studs as an upgrade, but elected for stock Elring gasket. So far I torqued in 3 stages to 80 ft-lbs, but wasn't sure about going to 90. The lubricating grease seems to be some useful stuff. It took me a while to apply it to washers, bolt threads and nuts as instructed.
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I also adjusted the valves. .010 on intake and .012 exhaust on the valve side per Mark Hutto
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I tried to mount the turbo in the same orientation as with the Callaway manifold, but hit an unexpected snag. I found that the compressor housing hits the block in the orientation as the Callaway turbo manifold. After wrestling with it for probably 45 minutes, I finally got it clocked to an orientation that would work, which is the orientation for TCD intercooler.
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I'm going to have to look at it and route the piping differently to use my air to air. So here are the parts otherwise all mocked up.
I have to look at the wastegate dump and see about getting that pipe remade. I didn't fit the exhaust but that may have to be adjusted slightly also. Good news was everything else seemed to fit about the same (I expected that).

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This is the space I am lookign to route the compressor outlet... maybe around the inlet pipe and down the frame rail to the intercooler piping. It's going to take a bit more time that I expected. It will also look homebrew silly, but I think that's pretty funny as long as it functions well.
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I also need to add fluids, reconnect cap/rotor/plugs/wires, and rewire a few items to work with MS2. Right now all but the TPS use harness adapters.
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

I had a chance to take the car on a 25 minute drive to make sure that air was bled from the radiator and gauges were all working.

A photo with the winter tires-- BBS Mahle RA's 15x7 et11.
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I ran without the intercooler and was certainly surprised to see that with a brief adventure into positive pressure, AIT's climbed above 150F (it was 50F ambient).
Here's a datalog also showing how my signal noise has cleaned up too

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For some reason my wastegate didn't seem to want to open so I actually hit boost cut at 160kpa. It freaked me out a bit at first until I realized what was happening. Glad to know it works... next will be to figure out why the wastegate didn't seem to open... I was expecting a scream due to the open dump at the moment, but I didn't have anything.

More slow progress to come. I will be fine tuning accel enrichment, VE table and such. I'm glad to say cold start and warmup enrichment was working the other day as the car started in 15F.


Update from yesterday:

All my parts arrived so I was able to make some progress today!

First, the setup without the intercooler:

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I had been investigating intercoolers and read a lot of theory but a few things really stood out.
-It should be sized to the flow requirements of the engine...
-Get the unit with the least amount of pressure drop (and most amount of flow)
-Place in area of turbulent air flow for maximum efficiency
-Air to air is really more efficient at the track. Water/air is arguably better for street use.
-Too big of an intercooler may simply take more time for you to reach boost threshold than the appropriate unit.

However, for track application, you need the largest intercooler possible to be able to dissipate heat after continued hard use. The larger the surface area, the better. Core depth isn't really critical as the deeper you get, there are diminishing returns and added weight.

A great read here if you wanted a bit more detail than Corky Bell's book:
https://www.mishimoto.com/engineering/2 ... selection/

Before I explain what size I selected, I did some reading about charge piping size. Basically, you size similar to the intercooler, as small as possible that will allow the CFM flow requirement. Bends and kinks will add pressure drop and make your system inefficient. As the airflow travels through a smaller diameter pipe, it will speed up. This is fine until the air travels up to a speed around mach ~.4. At these speeds, the total flow really becomes limited. So if the air flow rate approaches even .35 it is time to start thinking about upsizing intercooler piping.

My old setup used 2" piping. According to a few sources this pipe size is (street) rated for ~350hp and ~550CFM.
So for the street, this setup is probably close to the ideal size for use at my airflow levels (~380-400CFM).

2.5" piping: rated for ~575hp and 875CFM!
3" piping: rated for ~850hm and 1250CFM!

It also turns out that the compressor outlet is 2". So I elected to keep this 2".
Another suggestion is to increase pipe size as it steps past the intercooler. The idea is that the step minimizes as much pressure drop as possible post intercooler. I had 2.5" piping that I wanted to make work as it isn't too big to fit. It should provide slightly less pressure drop through to my intake manifold. The turbo will work a little less and outlet temperatures should be less, again generating an overall more efficient setup.

My previous intercooler was a 20x6.5" core. With the new piping arrangement, I decided I should bet a bigger one for hot days (I didn't like the intake temps I had with over 20F or more above ambient).

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With a new piping layout in mind, I explored intercooler sizes, layouts and placements. Ultimately I decided on an 18x11.5" core manufactured by EMUSA for less than $100 shipped. It is top inlet/out and I flipped this upside down in my head for a pipe routing that I thought would work.
The intercooler was as wide as I could go without modifying the car. It's about 50% larger than the one I had prior. It is placed where the AUX fan used to live, with a total width of 25". This is the size of the radiator cutout and the intercooler lives about 2-3" in front of the radiator.

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Basically the inlet would come from the engine bay and underneath, or from the headlight opening. With the outlet going up maybe near the headlights. When I tried it out with the intercooler only, it looked like I could make it work.

The airdam also had plenty of clearance and fit right up! The openings would be for an oil cooler, but on my car, they are obviously for my intercooler!

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So i checked to see how I could get compressor outlet to fit with the existing air filter setup. Fortunately, this Callaway pipe was close enough to work for me!

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Clearance with the airbox in place and couplers attached.

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The silicone coupler is a bending reducer opening the pipe to 2.25" gradually as it turns.
There is a 2.25" pipe elbow that bends the air again to be parallel to the ground.
The clearance to the radiator hose is pretty tight, but it isn't touching!

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Obviously it comes to the intercooler (it does this in a step to the 2.5" pipe size) and then out and turns up. (I didn't want red, but this was all my supplier had in 2.5" elbows):

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This is where a long silicone coupler brings the air past the headlight mounts and into another elbow into the engine bay.

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You will notice I am using the same divertor valve as I found the straight coupler with a hose port that would work. I did the same thing for the Idle air pathway as well! There's a step up to the 3" throttle body opening and that's all!

I am going to have a coworker add the AIT sensor on the left end of this 180* pipe, but otherwise that is all that's needed! I had a solution I will probably refine right now that sends diverted air back to the compressor intake, as well as the small amount of blow by that this engine creates.
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I don't feel like it's super pretty but I think overall it will be quite functional. After a brief test drive, spool doesn't really seem much different than without intercooler piping. Here's the video with the noises inside the car. I still need to finalize the wastegate dump, so this is OPEN with the microphone inside the car:

https://www.youtube.com/watch?v=VXgzQ_6ibo4

More updates to come as weather permits!
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by baders »

I'm following this Ted as there is some very valuable information here regarding supercharging/intercooling. I'm in a feasibility study right now regarding a little E46 M3 project I hope to get off the ground.
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by zinnocoupe »

Nice work here, As always about three levels in complexity above my ability. Amazing how much you've neatly added to the engine compartment. How much cooling effect do you expect from the intercooler? ( sorry if it was mentioned in there somewhere, if so I didn't see it) Good pics as well.
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

Good question.

The advantage of the intercooler is that as the compressor pressurizes the air, the air is heated significantly.

If my log without the intercooler you can see it heats up very quickly to over 100F when accelerating in just a single gear.

The intercooler exhchanges heat to bring this pressurized air back down close to ambient. The cooler intake temperatures into the engine mean that there is a safety factor to prevent detonation (which happens more easily when the air is warmer). The advantage being that the cooler the air, the more dense it is. So it is a safety mechanism that has a side benefit of adding some power if it works efficiently. The old intercooler I had worked great and was sized probably as big as I needed for even hard mountain drives. I simply wanted a bigger one to limit the overall temperature increase into the engine when at that road course. The bigger this is, the more it will withstand a heat soak condition where it can't exchange enough heat.

Here's the latest update:

My coworker was nice enough to help me out and weld on the IAT bung and a port for my wastegate signal. The aluminum barb was like $2.00 from Summit Racing and the bung had come with my IAT sensor originally.
My coworker did a great job with the welds and keeping smooth pathways on the inside of the pipe.

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I may have him help me finalize my wastegate dump, but I need to find a place to get the right sized piece of tube (1.5" I think). Basically cut and lengthen my current dump.

I was able to drive the car yesterday and get out on the highway since everything seemed to be working. It was ~60F and I was able to get Autotune going to start dialing in my tune.
I removed some timing to be safe and lowered my AFR table in a few places just to continue with tuning.

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Next up I did a datalog with a WOT run. I was super happy to see that IAT's only climbed about 15F. Much improved over the 50F without an intercooler.
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It made sense to plot my base runs on VirtualDyno. I did some reading and found the following:
Misuse of the smoothing feature can mask incorrect or inflated runs.The smoothing function in VD can be used to determine how accurate your power output is based on the consistency of power from Smoothing 1 to Max. A good rule of thumb is, if your power drops less then 12-15WHP from smoothing 1 to Max, then the run is accurate and will most likely make very similar numbers on a real Dynojet dyno, usually with 0-3%. If your power drops off 20-25WHP or more from smoothing 1 to Max, you should be aware that the VD chart may not be accurate and your power could be off 5%, if not more, from a real Dynojet dyno.
While it is great to have a number, I haven't been trying to get exact performance figures. Rather, I thought it would be interesting to compare estimated power levels before and after the changes. So I took some logs and filtered the data to the point that the data fit the rule of thumb above.

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Ignore the HP values and just look at torque-- I was only trying to plot max torque.

The first run from June 2nd Last year (Orange) was run with my Callaway Log, old noname intercooler and 2" piping at about 6psi. A couple of logs show this curve to be pretty accurate up to the specified RPM using the Smoothing rule of thumb.

In warmer weather I had bumped up the boost to about 10psi and taken a log (Green). It probably isn't a fair pull to use in terms of RPM and gear, but an increase of only 20lb-ft torque is all that this plot indicates. Maybe this is due to the richer fuel mixture, but I didn't extensively test 10psi so I can't really make a judgement on this curve. It was just interesting to see.

The other week I did a quick pull without an intercooler (Blue). This is with the new TCD manifold (ceramic coated), valve job, and cleaned up/opeend up exhaust flange coming off the turbo. Interestingly this log with increased IAT's still gave number similar to the old setup at 10psi. I think the Callaway manifold (sharp edges, poor pulse design) and exhaust flange were choking performance by adding increased backpressure and preventing max flow through the engine.

Finally, the new setup with intercooler and larger charge piping (Red). I know intake temperatures were much lower than all other logs due to ambient air and larger intercooler, but with the same turbo and same boost level this data shows about a 10% increase in performance. I have to do a more scientific datalog to get exact numbers, but at least I can see my changes have made a difference! Also note that max torque was 200rpm later, maybe more as it was still building.

The plan is to fix the wastegate dump and then eventually tune and settle at 8-10psi for track use.
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by baders »

Nice work ! It is addictive stuff this tuning caper.

The main advantage of charge cooling is not so much in outright power improvement per se. It is in the ability to enable a higher tune state (avoiding detonation) due to reduced charge air temperature.

To reduce intake turbulence, you could have even recessed that waste gate sensor further.

Does Auto Tune utilise VE tables ?
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

I was worried about the intake temp sensor being in the flow of air, rather than sensing the wall temperature, I think it's in a pretty good spot.

Yes, Megasquirt uses a VE table but that table is really only relevant for my configuration with injector size and such. I am still playing with it, but I can post it in table or 3D form if that was something you were interested in seeing...
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'79 635CSi Revival
'80 635CSi
'83 633CSi Callaway Turbo continued as 1988 535is Turbo
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by baders »

Sure I'd love to see that. I'm interested in VE for boosted applications. I'd have thought VE would be the cornerstone for your tuning ?
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

Here's current only tuned up to 120 kpa and ~4500rpm
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Interesting to compare to my map on the original setup in late 2016. It may not have been tuned the best at this point as I didn't have autotune and was just getting started with MS.
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I lost overall ve at 120kpa (but the comparisons were made summer vs winter so keep that in mind).

Also I gained ve in some of the middle (drivable) portions of the map.
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'79 635CSi Revival
'80 635CSi
'83 633CSi Callaway Turbo continued as 1988 535is Turbo
SOLD: '81 635CSi/A
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by baders »

Thanks ! Am I reading those correctly ? There appears no VE % readings above 86 ? I would have thought you would be setting above 100 for forced induction ?
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

This is why I was saying the actual VE values are of no use. I don't think they aren't a measure of actual volumetric efficiency, as the VE values are scaled for injector size. The global fuel constant (required fuel) in megasquirt will scale the table as required.

So if I want to run different injectors, I change the fuel constant and have a map that will be close to my old map with old sized injectors. At least that is how I understand it.


If it is a calculation of actual VE, it could be related to my altitude. I live at 5000ft (barometric pressure 84kpa) and lose a lot of performance due to that alone. So while people at sea level can run 6 psi and will be at 145kpa, I run 6psi and sit at 125kpa into the engine.
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by LandShark »

Tim, your tuning work is amazing. I know it sounds inane, but is there room for the air conditioning components?
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

LandShark wrote: Sat Jan 27, 2018 3:04 pm Tim, your tuning work is amazing. I know it sounds inane, but is there room for the air conditioning components?
Originally I thought about keeping it as the system was in place with the callaway setup. But the system was R12 and I didn't want to convert it... and the AC blower in the car didn't seem in good shape.

Now, there wouldn't be room for stock AC items. I removed the condenser and that's where the intercooler sits now. The compressor and belt is where the compressor outlet pipe is.

I am just getting into the tuning aspect, haha. I just wanted to get it running reliably (and smoothly) and understand my tuning method via megasquirt before trying to make it out to the dyno. I'm reasonably confident that very soon I'll be able to make it out to another track day with my tune on this car.
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'83 633CSi Callaway Turbo continued as 1988 535is Turbo
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

I took the car for a mountain drive a few weeks ago. We went up to 10,000 feet and I found that my car was running super rich below atmospheric pressures. It wasn't a huge deal as I was under load and got into boost a little bit, but even with EGO control at 10% authority I had mixtures of 13.5:1 where I should have been at 15.5:1 during cruise.

We stopped part way and restarting the car reset my baro setting. However, this introduced another problem. As I drove down the mountain, cruise became leaner and leaner. I suspected originally that this was baro correction as we were getting into more dense air.

Well I took the car for another mountain drive this weekend after adjusting baro correction to purely theoretical values and turning on my MAP daddy sensor for real time adjustment. I tuned it with autotune as I drove at 5500ft and stopped as we started to climb. Temperature was about 65F and I was able to notice that AFR's seemed relatively consistent based on the same throttle conditions as we went up to 7000 and 8000 feet. I did this with 0 EGO authority, so I suspect my baro correction is good and working.

On the return trip, I continued to autotune as we reached the flat areas. I have a slight miss it seems at low loads, even though AFR's looked good in 14-15 range in low load cruise.

Fast forward to yesterday, I start the car in 40F weather and instead of idling near 13.8, it was idling near 12:1 after Warm up enrichment shut off. I did not use EGO in this area, but if I can't consistently idle the same AFR, I have a problem. So obviously I have issues with temperature that is causing my problems. I suspected this over a year ago but am really frustrated as to what is going on.

I am starting to suspect that my injectors are too large (42# Green Giant's, authentic). I idle at pulse width of 1.3mS, and my dead time was set to .89mS. So i really don't have a large consistent pulse. Even at my max boost of 16psi, my duty cycle is only 50%. I am starting to think I should try putting in some ~30# injectors in and see what improves.

Still, how does temperature affect the mixture so much? I fixed my curve to 100% MAT correction, so I had no MAT adjustment from a few days earlier. Baro pressure really hadn't changed much. I need to look at pulse width and verify it was the same for both (I suspect it was).

I found this article and it is the only thing that makes any sort of sense. However, it doesn't explain why I am significantly richer:
Fuel Injector Heat soak
This one has taken me quite a while to narrow down. The symptom is that with a heat-soaked start, such as when I stop at the grocery store for 20 minutes, the car will idle significantly leaner.

The usual suspect is heat-soaked MAT but I found that even with MAT correction completely turned off I was still having the issue. The curious thing was that even at identical injector pulsewidths it was still idling much leaner. For instance, at normal operating temperature my idle PW is 2.2ms and will be at around 14.4 AFR. During a heat-soaked idle it will still be at 2.2ms but up around 16.0 AFR.

Why?

I started to hypothesize that the fuel injectors themselves were getting heat soaked and that the extra resistance in the copper coil windings was increasing the latency, therefore less of the 2.2ms PW was going towards delivering fuel.

I found some literature that showed injector latency can increase as much as 100ns which is .1ms.

If my idle PW is 2.2ms, that means the actual squirt is around 1.1ms with my normal 1.1ms latency. (squirt + latency = 2.2ms). If the latency is increased by .1 ms that means the squirt is reduced from 1.1ms to 1.0ms, a 10% reduction and certainly enough to explain the lean idle!

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A plot of injector resistance with time after a hot shutdown.


I plotted injector resistance with time after a hot engine shutdown and found that the resistance does increase significantly. I'm guessing it's the fuel that cools the injector when the engine is running. As soon as the fuel flow stops it heats up, increases the resistance which increases latency.

I was hoping that I could correlate heat soak of the MAT with heat soak of the injector but I don't think it's good enough to use for software compensation.

For now, there's nothing that can be done to compensate for this directly. Know that it exists and is not the same as MAT heat soak. I don't use closed-loop EGO at idle because it creates more instability than it solves.
I suspect my low pulse width is just non linear or not consistent for all 6 injectors. Smaller injectors and increased pulse width/duty cycle are what I am thinking of trying next. I'm going to explore injector dead time one last time before switching injectors...


I was able to get new injectors ordered and installed over the weekend. I am stepping down from 42#'s to 34#'s (@3bar) from some sort of 3.8L GM vehicle (L67 V8 supercharged)--Bosch#: 0280 155 811
These are high impedance injectors like stock and I was trying to keep the same type.

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My 1.3mS pulse width at idle changed to about 2mS and overall the car seems to run more smoothly. I have to go back through and revise my VE table, but yesterday the idle and cruise seemed smoother than before. Part of the reason I suspected the injectors as the problem was because the low speed cruise condition would give me a lean/surging feeling like the engine wasn't happy.

Well with my altitude, I have only about 83% of the air of people at sea level. So if they are close to the edge of being to big at sea level, I suspected they were actually too big for me up here.

A good article on the subject: http://www.enginelabs.com/engine-tech/t ... -with-fic/
The Problem

When an engine is driven on the street, it’s exposed to extended periods of time at idle, low speeds, and low engine loads. Which means the injectors will spend more time at shorter pulse widths (shorter spray time, less fuel delivery) than if it were only driven on a race track and rarely saw any driving below six-tenths. For many years this has put plenty of enthusiasts in a battle between drivability and injector size, often opting for the smaller injectors to retain its street friendly characteristics.

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“For a four-stroke engine your average fuel injector has two operating ranges – linear, from roughly 1 to 19 ms opening times [effective pulse width]; and nonlinear, 0 to 1 ms opening time,” explains Jilg. “In the linear range, the injectors will act in a very predictable manner. With smaller injectors [1,000 cc/min (95 lb/hr) and smaller], you will most likely only ever operate in this range. The nonlinear range comes into play on bigger injectors, over 1,000 cc/min, when at idle or even part throttle situations depending on the size.”

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Notice how choppy the injectors’ behavior becomes as they run into the nonlinear operating range (0 to 1 ms). The bigger the injector, the more pronounced and widespread the nonlinearity becomes. The bold horizontal black lines represent the estimated fuel requirements for idle (30 cc/min) and cruise (60 cc/min).

“The nonlinear range can become very unpredictable for injector operation and fuel delivery, causing sporadic engine behavior,” continues Jilg. “The majority of the problems people have with large injectors are at idle or cruise, because you are hitting this nonlinear range and the injectors no longer match close enough in flow rate or dead time. Currently, no one offers nonlinear range matching of fuel injectors, but we are working towards implementing this into our entire line of injectors.”

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In my 45 minute drive yesterday, the engine seemed to run smoother in the lower load (and lower PW conditions). I am hoping to drive the car tomorrow to work to see how the tune looks with extreme temperature variations (30F morning to 70F in the afternoon) and see if my tune is more consistent.

I need to verify my injector dead times (plotting Map/AFR on X axis vs PW on Y axis. Use intercept value from the trendline of the lower pulse width range), which I believe are lower than the suggested .9mS. Hoping to mess with that tonight.

A successful day today with positive news to report.

I installed the injectors and seemed to have smoother running in general. Based on some research I plotted a datalog to get an injector deadtime curve. This is MAP/AFR plotted against PW-- basically showing total fuel vs pulse width length (time). Extrapolating a trend lines gives a y-intercept for pulse width time. This intercept is the effective opening time (dead time).

Notice how there is a distinct change in the curve above 5KPa. Most injector's don't have a linear performance throughout their range. By setting dead time to match the trendline curve on the lower end, actual fueling will be most accurate since these opening and closing times are short. If the number isn't quite correct on the upper end, the VE table can be adjusted to compensate, and pulses are longer here anyway.
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This past week I was driving the car to work and home and saw immediate improvements in fueling in cold vs warm temperatures. It had to be the injectors causing my problems. So now I see fluctuations, but not as drastic as before. So this seems to be the change in air temperature causing my problems.
Since I am using Map daddy real time correction, I decided to research air density changes based on altitude. I set the barometric curve to measure values that I found online and have left those settings alone. Since temperature and pressure can both be changing at the same altitude, I have wondered if these two values ever fight each other. But at this point in time, I'm thinking that leaving it active and adjusting my MAT correction curve will get me as close as I can be.
The MAT curve is scaled down from the default, but I'm still working on it. I suspect my curve has to be scaled down more than those at seal level because my air density is lower than sea level.
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I found a nice open road out east and did a test boost run. Pretty happy with intake temps and it is interesting to see the change in coolant temps. This was 3rd-4th gear and a touch into 5th at 125mph. I think I need to re-gap my spark plugs as I had some breakup at 55000rpm. I'm at .032" and plan to bring them down to .025". Still running 91 octane, but notice 130kPa, that's 6.6psi for me, whereas it would probably be about 2psi if at sea level. I'm thinking of bringing it up tot 10psi to tune with, but only ~8psi for road course duty. All of the sizing software suggests the turbo doesn't hit max efficiency until 11psi or above, but I want this rig to be reliable...
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Today I was able to bring the car to a friends place to help me fix my wastegate dump and exhaust. I had never really wanted an open wastegate dump to begin with. George was nice enough to tell me he had a spare TCD turbo downpipe in his storage shed. So I decided to get it, hoping that the larger diameter and mandrel bends would further minimize back pressure post turbo. Maybe they do, maybe they don't but the main thing I wanted to fix was the exhaust connection and wastegate dump aspect. The old exhaust had a slight leak and wasn't an elegant solution. I decided that the new downpipe (ceramic coated) could likely be used and bought the vband hoping everything would fit.

Luckily we made cuts that were close to begin with so we only pulled the parts in and out a few times. My buddy asked for some photos of the work so here's a few of him cutting and welding as well.

The workspace

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Mocking up the new downpipe
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Getting the vband flange on there

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TIG welds:

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Comparison to the pipes we removed-- less sharp bends and no more bottle neck. Also I can run without a rear exhaust if I wanted and the O2/wideband sensor could still measure...:

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Fitment

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More tuning details to come, but the injectors have really made the difference to be able to continue tuning. The exhaust was about the last piece to the puzzle of the head gasket/turbo manifold upgrade.
http://www.Drive4Corners.com
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'79 635CSi Revival
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by zinnocoupe »

Great info here Tom. I see now after all this turbo stuff the real reason you’re getting more power is you are running at 55000 rpm. 😜
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1977 530i Partially restored and running now!
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

I have adjusted my tune file for a smoother idle because at 16* idle advance, the engine didn't run smoothly. Right now at 12* advance, it seems much more happy. Here is my .MSQ if anybody is interested in looking.

MSQ as of 4/5/2018: https://files.fm/u/bj3egw2k

The MAT and BARO correction seems to be working pretty well.
I tuned MAT with a scaled version of the default curve and decided to zero it out at about 80* F. So far it seems to work pretty good, I have been trying to drive it in cold mornings (30F) and warm afternoons (65+F). It turns out that in the cold with the scaled down curve, I would run slightly lean and then slightly rich in the afternoons. At least now the MAT curve was affecting my mixture, unlike last year.

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BARO curve I still need to test further but within 80-85kPA connected together with MAT, they seem to work pretty good so far.

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Lastly, AFR and VE tables.

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I'm not ready to share my ignition map, but I found removing timing from 30-40kPa region really helped to smooth out the off pedal jerkiness I had been having. I'll need to continue tuning this, but comments are welcome.
http://www.Drive4Corners.com
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

So some bad news: The delayed update is coming through because as I was tuning the MAT correction curve and general driveability, this happened.

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You can probably guess by the nature of the hit that the car won't be fixable and the cause of the collision may put me at fault. I was making a left turn and apparently did not see an incoming tuck. He didn't seem to see me either as he didn't hit the brakes or swerve in any capacity. This is my first major accident...

My wife and I were both fine and the car was still driveable minus some extra wind noise and tire rubbing on the way back home.


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I carry liability only, not comprehensive insurance, so I am on the hook for the repair. Which is fair-- if I was at fault I wanted to have to deal with the repairs (and save some $$ in the mean time).

I was really bummed bout it and was just getting it drivable to the point that I wanted to consider a repaint or other :cry:

After thinking about it, I have come to terms with the situation and the positives being that we were not injured, the expensive parts on the car are all fine, mechanically almost everything except the rear bumper and maybe gas tank will be usable in a new chassis.


Speaking of a new chassis, this car literally fell into my lap just before the accident. I had saved it from sure death being parted out and am slowly bringing it back:
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Did some searching on the previous owner to who I bought it from and found that this was Andy's car (Andy535iyes) from about 2008. It doesn't look like much maintenance has been performed since then, but here is the FS thread and a photo a decade ago.

http://www.mye28.com/viewtopic.php?t=54137

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Come to find out it doesn't have all the parts, but does have larger sway bars, larger e34 brakes, rear camber adjustment, good Bilstein's and Bav Auto springs, 3/46LSD and a rust free body :D

Reinstalled a couple doors for the tow home

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Put some wheels on it and took a short test drive.
After getting it running, the car actually drove down the road which a horrible death wobble and rear diff mount clink. Overall the exhaust on it actually sounds good and through the turns it was very stable and handled really nice. So after that first test drive I started feeling confident that this car could be a good chassis.

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I have been working on reinstalling small misc items such as turn signal switch, steering wheel, seat belt receptacles, wiper stalk, headlight switch, and various sensors and engine parts that had been removed. The other issue was wires cut on 3 of the 4 doors :roll: I have to get the C400 connector by the driver's speaker well and get them soldered together and hope the locks and windows work. I'm hoping I can get it all working.

Got the car running and driving and put some front seats in it and played with the alignment a little bit by visual inspection.

But onto some pictures of the new subject. The style 33 wheels on there were worn and didn't have centering rings. I'm not sure that I like them anyway, maybe I'll try them later.

Oh yeah, the pink tape was used to hold the door on when towing it. My wife likes it so it has remained for a little while.

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He's got a little name tag, so he's known as Burt now...
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I spy a lot more negative rear camber than what I'm used to with a lowered e28.

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The plan is to swap the good parts from the 633 into the 535is and use it as my track car now. The small dents on the driver's side are the worst of it, but this car seems to follow the theme of the 633-- a little rough around the edges but overall a solid base.I prefer the mechanical over the visual and I can fix the paint in the future still also.

The logistics are difficult to arrange for two chassis and two engine pulls so I am trying to figure out when or how I could make that work, and then leave the NA engine out of a car (or maybe put it back int he 633 so it can move and drive??).

I decided to get a start on fitting my 16x8 ET11 BBS RS211's or Rial mesh wheels and roll the fenders. I also figure I can fit BBS RK 17x8.5 et15 for light weight 17's if I want, or race slicks on naked m system wheels. The rears didn't fit on my 535i but did on my M5, so I decided to roll the fenders. Using a friends tool and advice, I worked on it last night.

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I used a heat gun to try and keep the paint flexible and heat the metal to ~130F then the Eastwood rolling tool with just a slight angle and slight pressure. The key was to be patient and work in small increments(and it really worked my arms as the rear diff locked up really well with the other side).

Here's where we started and based on experience with other wheels that fit, I needed about 9-10mm clearance to avoid rubbing when loaded. Mainly in hard cornering, we don't want a sharp edge to slice the edge of the tire. The E24 has a lot more clearance here than E28.

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Rear clearance (with RS211) at normal ride height after settling:

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It looks like I gained about 6-7mm, but the fender lip is also up and out the way so I think it will give me the clearance I need in hard corners. The photos above you can see there is more than 1/2" of room from the fender to the tire.

So overall it will be a big project the put the turbo engine and other parts in this car, but I think it is the next step for this project. I thought about other E24's for a replacement but there haven't been many rust free ones around. I looked at two and it just seemed like a lot of work with rust or just the other work required to get thinking running reliably. Plus this car is part way to my goal of a track car with welded in sway bar mounts, rear camber adjustment, a lighter/better balanced weight distribution, and satisfies in the looks department with the color and sports spoiler package.
http://www.Drive4Corners.com
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'79 635CSi Revival
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'83 633CSi Callaway Turbo continued as 1988 535is Turbo
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by GRNSHRK »

Wow Tom, kinda bitter sweet story :(

Really sorry to hear about the 6 getting totaled, but glad that you and the missus are OK [-o<

And just like that, a 535 iS falls in your lap :shock:

Go figure, kinda like good karma :wink:

Please keep us posted, we know you will =D>
:mrgreen:
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by Spasso »

Tom,
Your 633 took a hit in the worst possible way. Really hard to come back from that.
Glad you both are okay, especially with the truck and all.
I think you'll find that E28 will make a fine track car.
My brother has a 533 and swears by the handling.
Plenty of parts for these as well.
Best of luck.
(Time to add this one to your Sig.)
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

The last few weeks I started a house painting project (exterior) and have been busy. I'm not done with that but I did mess with the 535is. As I described, I was able to swap shocks and springs along with camber plates. I tried to drive the car a bit and found that it will stall out when the engine starts to get warm. I think one of the crank sensors is starting to fail as I replaced the coil, fuel pump (put in my Walbro external), fuel filter and still ended up getting the problem. I notice that if I kept the heat on high, it would take longer to happen. So I have some of those parts already on the 535is before starting this swap.

So I was able to arrange the shop space and got the cars over there earlier this Wednesday. I took off work Thursday and Friday and got there at about 6:30am to get started. My goal, which I thought might be possible, was to exchange the engines between the two cars by the end of Friday. I had access to two lifts, but one was really an alignment rack that didn't let me get the wheels off the ground (and didn't have functioning lifting jacks in the center, so they really were just in the way). Still, I knew it would be cheaper than renting two lifts for $40 per hour each.

Lucky for me, we are right at the longest daylight days of the year, so it was going to be light when I got up in the morning and I could work pretty much as long as I wanted to finish. Arriving at about 6:15, about my normal office job time. These guys who rent the space have a lot of BMW projects.

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Being a one man crew and having some the swap before, I knew it would take a while. Luckily I did get help removing the hood from the 535is the night before. My subject as we started.

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It was an exercise in futility getting the one piece exhaust off by myself with the alignment rack. But I did get it.

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Getting the engine ready for removal. We are close here.

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The hoist just fit inside the footprint of the lift. Here's me pulling it out; load leveler is key of course. It took me about 6 hours to get t this point. I'm not sure what the book time is on engine removal but I was pretty happy with this having taken so much time on getting the exhaust out.

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So in comes #2 to begin the work.

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The guy renting the space was able to come to the shop and help get the hood off the 633. He suggested that we lift it from the front so that he could park his car inside the shop and work while I worked. So I did that, but still had to jack up the rear to twist the driveshaft and get the hardware off. But this was working under the turbo. Getting the vband and exhaust was quick! But it did take some time to get the downpipe off...

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He helped me for the actual pull and we were able to get the engine out with the turbo and manifold installed. At this point, we dropped the 633 and rolled it back so that the hoist would have clearance to roll into the front of the rack. I had planned this out a bit and it worked as expected, with just enough room.

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I also got some help getting the engine in place in Burt. This took a while since the natural engine balance was a little off with the turbo and manifold. Weight was balancing the motor mount on the passenger side lower to the ground. But we got it.

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This was where I ended for the night, which was probably after about 13 hours. I was happy with what I got done and how fast I got it done. It meant I might be on track to finish by Friday night.

See you guys tomorrow!
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It was a long day and I ended up getting back to the shop at about 6:45 the next morning. I started reassembling Burt with the turbo motor and had to play with the gauges. I don't have a ton of photos, but it was reinstalling the driveshaft and turbo down pipe. I couldn't get the exhaust on due to the rack, so I focused on other tasks. I just got the gauges close so that AFR would work on my drive home. I didn't bother messing with getting everything finished and working just yet. It is a bit of a mess of wires. But I did wire them with the intention of mounting above the center vent blank plate.

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Here's a picture of my oil drain as people always wonder how this ends up with the bottom mount. I didn't touch any of this during the swap. Last time I did, but it is actually doable without removing the turbo manifold.

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I reinstalled the turbo parts without intercooler because my E24 setup wouldn't fit. To save time, I got my callaway intake pipe installed and ran non-intercooled to drive home. The car started up just fine, but I did have to reconnect the starter wiring. Ralph was able to help me install the hood at this point. And here is Burt the now turbo 535is.

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It being about 1:30pm, it meant that I was almost a bit behind schedule. I had to get going on the 633 engine install. So Burt got to watch front row as his engine got dropped into the 633. I did this pretty much all myself as Ralph was working on his own projects.

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So I put my head down to get the rest of it back together and running. He did help me put the hood on the 633 before he left for the day At one point we also moved Burt in front of the 633 so that I could install the exhaust.

The parts all swapped over without a hitch. Even the 265/6 and sheetmetal console into the '88 535is. I had been worried about the shifter.

I ended up getting it all back together and ready to start at 7:00pm. It cranked and cranked and wouldn't start. After some investigation, I found a power wire to the main relay had broken. So once I rigged something up, the car started up. At this point, I knew I could wrap up and get both cars home. So at about 7:45pm I drove Burt home.
It turned out to be about 26 hours working for me to do the two engine swaps, which I think is pretty darn good considering one was turbo. I would be interested to know what the E28 engine R&R 'book time' is. I wasn't trying to slap it together, but I did want to get it out of his space sooner than later. My wife also wanted my time on the weekend, so I wanted to finish ASAP.

The hood wouldn't close with my non-intercooled setup, but here was Friday evening

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So now that that car is home, it seems like a have an even longer list of things to do just to get it on the road and driving again:

-Reinstall front sway bar ( I took it off in advance)
-Mount gauge pod
-Finish wiring gauges/gauge lights
-Mount intercooler and map out IC piping
-Order piping and couplers to install intercooler
-Reinstall front 535is spoiler. Spray paint it maybe?
-find source of battery drain
-Bring car in for an alignment
-finish aligning doors?
-continue working through Megasquirt tuning

More updates to come
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'79 635CSi Revival
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by jps635 »

Good skills, that really is some achievement - you obviously know what you're doing.
Curious though why you put the 5 series engine back in the 6, given is write-off .
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Re: 633CSi Turbo - Not a Callaway Anymore

Post by tschultz »

The major thing for me was to have that car mobile so that I could move it. So I put it back together and have a running driving car right now until I decide where i want to part it out at. Ultimately I think that is what will happen with this one... I'm not sure anybody would want the shell.

Instead i may use the rust free parts as a donor for my euro spec 635 if I was interested in going that deep into repairs. In the mean time, I'm going to hold onto it until it makes sense to start parting it.
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Re: 633CSi Turbo - Not a Callaway or an E24 Anymore

Post by tschultz »

I was able to get some more items done on the car. First was to get the wiring a bit cleaner and see what ideas I had about the gauge pod. I wired in the lighting and decided to see if I could get the wiring through the blank plate of the HVAC. By filing out one of the ribs of the blank plate and making the opening just a bit bigger, I was able to get all of the connectors through. I also can remove all the gauges and move them later without anybody really noticing.

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I'll have to figure out where I want to mount it to be solid, but for now it is just setting in place until I decide angle/position and method of mounting.

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Next up, I removed the front valance and remaining AC bits. I was able to get the intercooler setup in place. It may not be finished yet, but I am hoping I can just tweak what I have currently. I cut very little from the valance near the tow hooks to put the intercooler in front of the radiator and inside the valance. The intent is that I could install euro bumpers and leave the piping and intercooler as is. An air dam would cover the cuts I have made in the valance. I did NOT want to cut out any of the nose or hack into the headlight parts. I wanted oem functionality.

This is what i cut from the valance.
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Here's the intercooler placement. What I don't like is at the moment the pipes hang too low. I'm going to see if I can bring everything up another inch or two, but I wasn't having a lot of luck when I tried the first time. I just had to make sure it would even be remotely close. The IS spoiler will give OK airflow here...

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The inlet/hot side is pretty much the same as I laid out in the 633. The cold side is somewhat different. Instead of bending 180* up and into the headlight compartment, I had to go under the power steering pump.

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It turns up with an elbow at the engine mount to shoot up here.

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I can now get the hood closed too. It is tighter space wise than the e24 up front near my air box.

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Replaced a tire rod and hoping to get an alignment today. Also seemed like my alternator had starting failing so I will determine later today if that is resolved or not.

Unfortunately while under there, it seems I have an oil leak from the passenger rear of the engine. Maybe the duck gasket on the back of the head? Seems to drip onto the turbo down pipe and when parked. :x :evil: I'll have to re-check the valve cover just in case.

EDIT: I think the oil leak was just a loose valve cover nut. Also, book time is about 8.3 hours for engine R&R with all necessary tools and such. Not sure if that includes removing exhaust or not.
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'79 635CSi Revival
'80 635CSi
'83 633CSi Callaway Turbo continued as 1988 535is Turbo
SOLD: '81 635CSi/A
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