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m635 Exhaust options

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raykoke
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Re: m635 Exhaust options

Post by raykoke » Tue Mar 27, 2018 2:24 am

Mine took 6 months to arrive... 6 years ago....

It's a nice item.

Cheers,
'85 ///M635

brickwhite
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Re: m635 Exhaust options

Post by brickwhite » Fri May 11, 2018 3:10 pm

Having the headers JETHOT coated...


Before

Image

$355 (with shipping) dollars later.... Should be here next week....
- 12 535i
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Re: m635 Exhaust options

Post by ericono » Fri May 11, 2018 6:34 pm

Are your new headers carbon steel or stainless?

How do the the rectangular pieces that bolt to the head look? Are they in line and flat? Did you try test fitting them already?

What coating are you getting?

Thanks,

Eric
'85 M635, '00 528iT, '98 Z3

brickwhite
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Re: m635 Exhaust options

Post by brickwhite » Fri May 11, 2018 7:14 pm

Headers are Stainless. The flanges seemed pretty straight. I haven't test fit them yet.

https://www.jet-hot.com/colors/

0100-Classic Polish Silver (Only with Extreme 1300)

Not sure on how they did the coating with the flanges.

I'll post some pictures next week when they come in.
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brickwhite
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Re: m635 Exhaust options

Post by brickwhite » Tue May 15, 2018 7:51 pm

My headers came back today from Jet-Hot coatings.

These are EBay from Germany Stainless Exhaust headers.

Look pretty good.. Looks like Chrome feels like powder-coat.

Better packaging than I sent...

Image

Dent was there already...

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Image

Image

Inside is coated too

Image

Image

Image
- 12 535i
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- 63 Triumph Tr-4

brickwhite
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Re: m635 Exhaust options

Post by brickwhite » Thu May 24, 2018 6:47 pm

The Old Comes down...

Image

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And fix other stuff while there!

left Tranny mount if very squishy.

Steering box subframe mount it torn...

Image
Last edited by brickwhite on Thu May 24, 2018 7:59 pm, edited 1 time in total.
- 12 535i
- 92 325ic
- 88 535is
- 85 M635csi

- 63 Triumph Tr-4

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ericono
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Re: m635 Exhaust options

Post by ericono » Thu May 24, 2018 7:55 pm

Good progress. It was certainly time for some new exhaust pieces. Looking forward to hearing how pulling the current header off goes. I got mine off, but had also dropped the front cross member due to planned work on the suspension, and it was still a bit of work getting them off. I had to remove the large heat shield protecting the A/C lines.

I like your TR4 in the background. I've had TR3s and 6s, but haven't gotten a 4 yet. Seems like it would be a good mix between the 2.

Keep up the good work!

Eric
'85 M635, '00 528iT, '98 Z3

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Re: m635 Exhaust options

Post by cofred » Sun Jun 10, 2018 1:03 pm

Eagerly anticipating updates......
Heath
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Re: m635 Exhaust options

Post by Sixracer1 » Mon Jun 11, 2018 8:41 pm

Looking to do a new exhaust on my car this summer. How do you like the Super Sprint?
'85 M635CSi #64
'01 325XiT
(Formerly "Sixracer")

brickwhite
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Re: m635 Exhaust options

Post by brickwhite » Mon Jun 11, 2018 10:14 pm

it looks nice, but don't have it installed yet, have to replace center bearing and clutch .. it will be a while.
- 12 535i
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Re: m635 Exhaust options

Post by EdwasRed » Wed Jun 20, 2018 3:48 pm

Just ordered rear muffler 18-12-1-309-004 for my Shark. Supposed to be here in a week...fingers crossed.
1985 635CSi M Euro M88

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Re: m635 Exhaust options

Post by brickwhite » Mon Jun 25, 2018 10:12 pm

More removal...

Exhaust manifold....(not original euro manifold)

Start with the 24 9mm nuts 4 nuts per exhaust port.

Image

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Drop the sway bar and front reinforcement bar.

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Pull out the manifolds.

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out!

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Nice weld job!

Image
- 12 535i
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Re: m635 Exhaust options

Post by GazM3 » Mon Jun 25, 2018 10:25 pm

Those old headers look fantastic. Can’t understand why you are replacing them lol
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DRPM635CSi
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Re: m635 Exhaust options

Post by DRPM635CSi » Mon Jul 23, 2018 6:20 am

For those in RHD-land:
Image

More

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Jono B good
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Re: m635 Exhaust options

Post by Jono B good » Sun Aug 05, 2018 5:53 pm

brickwhite wrote:
Tue May 15, 2018 7:51 pm
My headers came back today from Jet-Hot coatings.

These are EBay from Germany Stainless Exhaust headers.

Look pretty good.. Looks like Chrome feels like powder-coat.

Better packaging than I sent...

Image

Dent was there already...

Image

Image

Image

Inside is coated too

Image

Image

Image
Beautiful, any updates?
Image
~Cirrusblau-Metallic~

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DRPM635CSi
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Re: m635 Exhaust options

Post by DRPM635CSi » Mon Aug 06, 2018 2:12 am

Looks awesome like something out of a Terminator movie. Not for me, but it's certainly going to make the engine bay 'pop' when you open the bonnet. Shame about the dent, I guess that's a risk you have to take buying from somewhere where it has to be posted. I'd have cut the join tags between the flanges myself before the jet coating, but again that's just personal preference.

Mine too had joined flanges and incomplete welds when I got mine. I corrected all that before getting them coated. The pipes were fine, but the flanges were total ghetto like an afterthought they just didn't care about. They looked like the fabricator just lost all interest in the job after the pipes were done and he flung them at the apprentice to do the flanges with some scrap plate they found in the dumpster outside. Here's what they looked like when I got them:
Image
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ericono
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Re: m635 Exhaust options

Post by ericono » Mon Nov 05, 2018 8:06 pm

DO you have any after pics that show what you did to them before and/or after sending to get coated? Did yours come from Germany as well?

Eric
'85 M635, '00 528iT, '98 Z3

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Re: m635 Exhaust options

Post by baders » Tue Nov 06, 2018 2:14 am

DRPM. What was the source for those headers ? Will they clear engine mount/control arm mount/steering box for RHD ?
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Re: m635 Exhaust options

Post by bpoliakoff » Tue Nov 06, 2018 3:37 am

Something I find interesting is that on the euro 635s at least the E12 based cars, the exhaust does not exit in center of the car but angles out to the left. This is evidenced by the cut out in the rear pan being off center to the left, Is this not so on the later euro cars? I ask this as all the rear muffler pictures I see posted for any cars have the exhaust exiting dead center. When i bought my car it had a Billy Boat system, and the muffler was built with the pipes correctly fitted to exit left and fit perfectly. Possibly the previous owner brought the original system in and had it matched to size as BB is a local manufacturer
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flickr.com/photos/bertsphotos.

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Brucey
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Re: m635 Exhaust options

Post by Brucey » Tue Nov 06, 2018 9:03 am

baders wrote:
Tue Nov 06, 2018 2:14 am
DRPM. What was the source for those headers ? Will they clear engine mount/control arm mount/steering box for RHD ?
they look like fritz's manifolds to me,

http://www.fritzsbits.co.uk/exhausts-manifolds

so yes they are designed to clear the RHD steering box arrangement.
DPRM635CSi wrote:...Mine too had joined flanges and incomplete welds when I got mine. I corrected all that....
Cutting the flanges to separate them isn't a bad idea. However whilst it doesn't seem to be a problem, if you want to relieve the thermal stresses on the flange (which expands at a different rate to the head) then all that is required is cutting a couple of slots between each exhaust port, to leave a 'Z' shaped connection. [If you are worried about looks then you are wasting your time; the water rail on an M88 and the block slant see to that].

However 'welding them all the way round' is of highly questionable benefit; the reason they are not 'welded all the way round' is almost certainly that the exhaust is more likely to fail if you do this. Such failures are not uncommon in cheapo e-bay manifolds;

Image


In the fritz's system The pipes are welded all the way round to make a seal near the head face, and the two welds on the outside are positioned so that they are unlikely to suffer thermal fatigue. This method of construction has been established over many decades of racing experience; AIUI Fritz's use a subcontractor (who makes road and race systems for all kinds of cars) to make their exhaust systems; the design and method of manufacture are very well proven.

In case you are in any doubt about the standards of craftsmanship concerned, just look at the finish inside the fritz's system near the exhaust ports and compare it with Brickwhite's pictures above. The former is smooth and offers no obstruction to the gas path and the latter is, well, er, 'not like that'. Nor are many (most?) systems that are 'welded all the way round'.

Given the choice between pretty flanges and a good gas flow path I know which I'd rather have....

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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DRPM635CSi
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Re: m635 Exhaust options

Post by DRPM635CSi » Sun Nov 11, 2018 3:56 am

baders wrote:
Tue Nov 06, 2018 2:14 am
DRPM. What was the source for those headers ? Will they clear engine mount/control arm mount/steering box for RHD ?
They're the Fritz's Bits headers from UK. Yes, they are designed to clear the steering box and engine mount in RHD. You give up equal length primaries for that though. That's the compromise you must make if you're RHD. Equal length primaries is a lot less important in fuel injected engines though, so the power loss would be negligible and probably completely unnoticeable in all but the very extremes of performance just before the rev-limiter cuts in.

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Re: m635 Exhaust options

Post by DRPM635CSi » Sun Nov 11, 2018 4:39 am

Brucey wrote:
Tue Nov 06, 2018 9:03 am
Cutting the flanges to separate them isn't a bad idea. However whilst it doesn't seem to be a problem, if you want to relieve the thermal stresses on the flange (which expands at a different rate to the head) then all that is required is cutting a couple of slots between each exhaust port, to leave a 'Z' shaped connection. [If you are worried about looks then you are wasting your time; the water rail on an M88 and the block slant see to that].

However 'welding them all the way round' is of highly questionable benefit; the reason they are not 'welded all the way round' is almost certainly that the exhaust is more likely to fail if you do this.
I welded them all round to match the way the M30B34 headers also by Fritz's Bits were supplied. I couldn't find a justifiable technical reason for why the M88/3 headers were so backyard looking compared to the comparatively professional finished looking M30B34 headers with their removable leg-out-of-bed cylinder #1 primary that goes under the engine mount. The M30B34 headers have suffered no ill-effects whatsoever from having separate flanges and being having the tubes welded all the way round to the flanges, so I anticipate no issues either by doing the same thing to the M88/3 set.

There was no flex at all from the flanges when they were cut to separate them. Everything remained in perfect alignment. Despite the engine cant and the water pipe being there, I am having mine fitted without replacing the steel heat shield. I don't think the steel heatshield will clear the Fritz headers anyway, so it can't go back on regardless. The ceramic coating is there to replace the heat soak problems that can be expected when the factory heat shield is discarded.

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Brucey
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Re: m635 Exhaust options

Post by Brucey » Mon Nov 12, 2018 10:56 am

FWIW I bought a set of Fritz's headers (in fact a full system) for my M30 about fifteen years ago and the flanges were welded as per the M88 set you have just bought. I guess since I bought mine they have started to make the M30 headers differently (i.e. 'welded all round') but they have continued to make the M88 headers in the same way as they used to make the others too.

It might be something as simple as which subcontractor they use to make the headers in question, but there are other possibilities, e.g. that they think they can get away with the (cheaper* and less good IMHO) 'welded all round' approach on the M30 engines but for (tuned especially) M88 engines it won't work so well. As I said before I have seen plenty of the 'welded all round' types which have cracked; the thermal stresses around that joint are about as horrible as you can imagine, and they just get worse when you weld it all round, plus the microstructure in the weld HAZ just loves to have a crack running around it.

(*) Note that the current price for a set of RHD M30 headers from Fritz's is only a bit more than it was fifteen years ago. I suspect that they have been able to hold the price down by making them more cheaply, and 'welded all round' may well be part of that.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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Re: m635 Exhaust options

Post by ron » Mon Nov 12, 2018 11:21 am

Brucey wrote:
Tue Nov 06, 2018 9:03 am
In case you are in any doubt about the standards of craftsmanship concerned, just look at the finish inside the fritz's system near the exhaust ports and compare it with Brickwhite's pictures above. The former is smooth and offers no obstruction to the gas path.
I bought a full M88 Fritz's system about 2 weeks ago. You could cut your finger on the inside of the ports. I smoothed everything with a high speed grinder and small flapper wheel.

I contacted Richard and he apologised and was going to have a stern word with his sub-contractor.
They are ALWAYS rustier than you thought!!!!!!
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Brucey
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Re: m635 Exhaust options

Post by Brucey » Mon Nov 12, 2018 9:24 pm

that is a bit disappointing. Even so I would warrant that they were still much better than the average cheap crap on ebay.....?

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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