Going staggered - opinions wanted

Post in this forum for topics relating to tires and wheels

Moderators: GRNSHRK, ron, bfons

Post Reply
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Going staggered - opinions wanted

Post by DRPM635CSi »

Here's one for the wheel gurus in here. First off a disclaimer: I'm a non-staggered guy. I don't believe staggered wheels belong on anything less than a 911.

Now that's out of the way, here's what's happening. I have a bog stock M635CSi with (supposedly) 286bhp. It currently sits on this set of 1988 ALPINA closed lugs in 17x8 winter wheel size with 235/45-17 tyres all round. Handling and road holding is great. No complaints. Perfectly balanced, looks great, I love it.

Shortly the car will be getting this chip and these Fritz's Bits headers installed. Rich @ Fritz claims the headers are worth 21bhp and SSSquid claims the chip will be worth 15bhp. I don't expect to be able to prove or make good either of those optimistic claims on my car, but together they must be worth something, so for the sake of this exercise let's be ultra-conservative and say combined together, maybe an additional 15bhp will result plus some extra torques as well. This will take the engine power over 300bhp.

I like my ALPINAs and want to keep them. My options for going staggered therefore are limited to a pair of matching 1988 closed lug 17x9.5" running 265/40-17 tyres. This webpage tells me I need a 9.5" wide rim to run a 265 and this webpage tells me I need to run a 265 tyre if going staggered to match the rolling diameter + sidewall height of the fronts.

Now given all this, do you think 300+ bhp justifies going staggered on an M635CSi when that stagger will be as extreme as an extra 30mm tread width + an extra 1.5" of wheel width in the rear?

Edit: The car already has a rear strut brace installed under the parcel shelf, so the loads of bigger wheel/tyres in the rear should not overpower the suspension's ability to control them.

Image
Image
GazM3
Posts: 1791
Joined: Wed Oct 26, 2011 12:55 pm
Location: Melbourne, Australia

Re: Going staggered - opinions wanted

Post by GazM3 »

I have staggered wheels by 1” but tyres are only 235 and 245. I run more front negative camber and a thinner front roll bar and I have neutral to oversteer handling. I have same fritz headers with chip and 240rwhp.

With good quality tyres and a working lsd have no problem putting down with 245 Michelin ps4.
BMW’s
84 E24 M635csi
90 E34 M5 3.6
94 E34 540i/6 SC E85
97 E36 M3 euro SC U/C
97 Z3 2.8 widebody

OTHERS
11 Audi S5 3.0 SC
19 VW Amarok V6
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

GazM3 wrote: Thu Jul 26, 2018 6:09 am I have staggered wheels by 1” but tyres are only 235 and 245. I run more front negative camber and a thinner front roll bar and I have neutral to oversteer handling.
Did you especially find you were still getting too much push after going staggered such that the neg+soft sway was necessary to dial it out?
GazM3 wrote: Thu Jul 26, 2018 6:09 am I have same fritz headers with chip and 240rwhp.
Gazzle, do you have any power/torque curves for that chipped engine of yours pre+post install you could share with me?
sskoda
Posts: 54
Joined: Thu May 29, 2014 12:17 am
Location: N Ireland
Contact:

Re: Going staggered - opinions wanted

Post by sskoda »

What's the intention? Do you plan to drive harder, significantly faster? I would submit that there is no need to change anything, and if you did want to spend some money, an upgrade to the tyres might see more gain than an increase in width.
Wider tyres are effectively (a non-expert view) for more grip - large HP on skinny wheels will spin them up. So unless you are planning to start launching harder, there's no need to alter your current setup - notwithstanding that grip/traction is closer related to torque than HP anyway, and you can use tiny skinny wheels on a high HP vehicle as long as the torque is low, as LSR cars would demonstrate.
Current projects: E21 316 / E24 635i / E24 M635csi x2 / E28 M535i x2 / E30 325i Sport x3 / E32 740i / E34 525tdsT / E34 535i Sport x2 / E34 550i / E36 M3 x4
GazM3
Posts: 1791
Joined: Wed Oct 26, 2011 12:55 pm
Location: Melbourne, Australia

Re: Going staggered - opinions wanted

Post by GazM3 »

I just started upgrading bits to the suspension.

Firstly done the front bushes and steering hardware, and put the upgrade sterringbracket on for a good improvement.
Then added some custom offset roll centre adjuster blocks to get -2deg. Helped for sure but the big change was when I put the front brace on it all came to life. Put the rear brace on after and it made it neutral to oversteer now.

The final puzzle was the Michelin ps4 tyres. Handling now is just amazing and that’s without doing any rear end bushes or alignment.


On the power I dynoed it when I first got it (had fritz headers). Got 161rwkw (215rwhp). I added chip, replaced injectors, replaced rubber intake bellows with silicone and refreshed linkages, aligned throttle bodies and new plugs. I think the chip on its own made a small difference but hard to quantify as different. Dyno on different days.

I’ll see if I have the plots.
BMW’s
84 E24 M635csi
90 E34 M5 3.6
94 E34 540i/6 SC E85
97 E36 M3 euro SC U/C
97 Z3 2.8 widebody

OTHERS
11 Audi S5 3.0 SC
19 VW Amarok V6
GazM3
Posts: 1791
Joined: Wed Oct 26, 2011 12:55 pm
Location: Melbourne, Australia

Re: Going staggered - opinions wanted

Post by GazM3 »

Found them



First one
Image


Second one
Image
BMW’s
84 E24 M635csi
90 E34 M5 3.6
94 E34 540i/6 SC E85
97 E36 M3 euro SC U/C
97 Z3 2.8 widebody

OTHERS
11 Audi S5 3.0 SC
19 VW Amarok V6
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

sskoda wrote: Thu Jul 26, 2018 11:49 am What's the intention? Do you plan to drive harder, significantly faster?
I would like the ability to corner faster and accelerate earlier coming out if the conditions and speed cameras allow without a nagging feeling in the back of my mind that the car might suddenly snap oversteer and swap ends on me wrapping itself around the nearest metal light pole.

I don't want to induce understeer because nobody enjoys understeer, but by the same token I don't want a car that will eat or shred rear tyres for being undergripped and I do want the ability to be able to just mash the throttle into the carpet in 3rd gear and leave it there until my fear of the speed cameras takes over without the added fear that the car will launch me up a tree backwards if I do that.
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

GazM3 wrote: Thu Jul 26, 2018 10:08 pm the big change was when I put the front brace on it all came to life. Put the rear brace on after and it made it neutral to oversteer now.
Suspension tower top strut braces?
On the power I dynoed it when I first got it (had fritz headers). Got 161rwkw (215rwhp).
You had a pretty healthy car to begin with in that case. The rule of thumb with conventional Panhard layout cars is that the kW engine number is what you'll see on a dyno at the rear wheels in bhp isn't it? So, using that theory, 210 rwhp is what should be expected yeah?
I added chip
What flavour chip have you got Gazza? And what's your car's VIN?
GazM3
Posts: 1791
Joined: Wed Oct 26, 2011 12:55 pm
Location: Melbourne, Australia

Re: Going staggered - opinions wanted

Post by GazM3 »

I have the fritz chip. I don’t buy into the power conversion from rear wheels to flywheel debate as there are 2 many anomalies with it. The fritz chip should give more timing which is what lacks with the std setup.

If u wanna start tuning it up prob good idea is to invest in an AEM air/fuel gauge and wideband. You can get some good gains by playing around with the airflow meter spring, and if you have an idea what you are doing with the mixtures I can get some nice results.
Can get them of eBay for $280ish. I just fix mine in with Velcro so no screws into precious trim etc.

And yes it’s a strut tower brace. When I put the front one on everything worked together. There must be lots of front end flex in the e24 chassis. Installed one on e34 and hardly noticed any difference
BMW’s
84 E24 M635csi
90 E34 M5 3.6
94 E34 540i/6 SC E85
97 E36 M3 euro SC U/C
97 Z3 2.8 widebody

OTHERS
11 Audi S5 3.0 SC
19 VW Amarok V6
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

GazM3 wrote: Fri Jul 27, 2018 5:15 am I have the fritz chip. I don’t buy into the power conversion from rear wheels to flywheel debate as there are 2 many anomalies with it.
Nah, it's just a dodgy bros., back of fag packet, rule of thumb thing obviously. No-one's gonna beat anyone up over it. Every car's gonna be different on every day of the week.
And yes it’s a strut tower brace. When I put the front one on everything worked together. There must be lots of front end flex in the e24 chassis.
Oh heaps! The E24 chassis is like jelly wrestling in a bouncy castle on a shaker table floating on a boat above an erupting undersea volcano. The first things that need to go in are strut braces. It's just a shame the rear one is such a complete bastard to get in there.
User avatar
Da_Hose
Platinum Member
Platinum Member
Posts: 3236
Joined: Fri Mar 07, 2008 8:15 am
Location: Santa Ana, CA.

Re: Going staggered - opinions wanted

Post by Da_Hose »

I only drive my M6 on the road, and it is setup with euro headers, Conforti chip, A100 exhaust gear, and silicone reducers instead of accordions. Pretty much what you are looking at power-wise. I have not dyno'd, but I see people with my same configuration posting numbers around 290HP.

I upgraded my rear sway bar to an M5 version, and the rest of my suspension is far from stock. I converted to poly-filled rear subframe bushings, and fabricated spherical bushings for my control arms. So I have a VERY tight rear suspension. Up front I have installed HD bushings everywhere and fabricated custom roll center spacers. I don't have a strut bar in front, though.

I am running 275/35-18 in rear, and 245/35-18 in front. That setup doesn't understeer unless I really cook into a corner, or if I just hammer it mid-turn. Coming out of turns, I feel very safe to use all the throttle with my staggered setup. If I had stock wheels all around, I would have to be way more careful coming out of turns. In all, I am quite happy with a staggered setup on my M6.

Jose
1987 M6 - My dream car
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Going staggered - opinions wanted

Post by Brucey »

there is a thread somewhere which has comments in it from a BigCoupe member involved in performance tyre development. IIRC he doesn't think that staggered wheels are really necessary on this type of car. Looks aside, I agree; there is plenty to do with suspension setup and weight distribution before you need wider rear tyres. Maybe if you had another 150bhp things would be different. Gawd, if the optimistic increases in bhp created by bolt on goodies were real, and all added up, buying an extra 150bhp would be easy....

IIRC most NA tuning will increase peak power more by increasing the rpms at peak torque than increasing peak torque itself; this being the case the thrust the tyres are transmitting to the road is about the same in each gear as it was before, just held until a higher road speed. This means the effect on the car's handling is different than if (say) you whacked a turbo onto it and made 300bhp at 4000 rpm or something.

Pragmatically speaking, all running wider tyres is likely to do is increase your tyre bill; the tyres on this car are meant to be rotated front to rear (to even out the wear) and you obviously can't do that any more if you have a staggered set fitted. This can mean that the tyres are worn out in about 1/3rd the usual mileage.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
Jono B good
Posts: 188
Joined: Mon Jun 04, 2018 10:33 pm
Location: Victoria, B.C., Canada

Re: Going staggered - opinions wanted

Post by Jono B good »

Let me ask a noob question here so we all have LSD's I am going to assume that the right wheel will always spin first from a stand still point, is this correct? And I recently pulled the spare wheel out to remove dead weight, but the left side of my 6er rose about 2" looked really odd to say the least I should probably replace the spare for proper weight distribution.
Image
~Cirrusblau-Metallic~
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

Brucey wrote: Fri Jul 27, 2018 10:41 pm there is a thread somewhere which has comments in it from a BigCoupe member involved in performance tyre development.
This one?
Pragmatically speaking, all running wider tyres is likely to do is increase your tyre bill; the tyres on this car are meant to be rotated front to rear (to even out the wear) and you obviously can't do that any more if you have a staggered set fitted. This can mean that the tyres are worn out in about 1/3rd the usual mileage.
I agree with you. I may still go ahead and do it anyway if a pair of wheels in the right size present themselves to me at a not ridiculous price I can use. I will still keep my square set of 17x8's though. If I decide to keep the staggered setup, then I'll just rotate the four fronts around the front axle as necessary and keep the rears for the rear only obviously. It's something I would like to try even if only for aesthetics, though I concede it is probably not going to be necessary from a shear grip perspective.
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

Jono B good wrote: Sat Jul 28, 2018 2:57 pm Let me ask a noob question here so we all have LSD's I am going to assume that the right wheel will always spin first from a stand still point, is this correct? And I recently pulled the spare wheel out to remove dead weight, but the left side of my 6er rose about 2" looked really odd to say the least I should probably replace the spare for proper weight distribution.
Could you please explain your thinking for why the right wheel will spin first? Assuming coefficients of friction are identical between the two rear tyres and the roadway, tyre pressures same, etc, why will the right wheel spin first? Are you thinking about weight distributions? The engine spins CW when viewed from the front so the reaction torque is down on the RHS of the car (or lifting the LHD driver if you prefer). Have you considered that?

I'm genuinely curious. Why do you think the right wheel will spin first?
User avatar
Jono B good
Posts: 188
Joined: Mon Jun 04, 2018 10:33 pm
Location: Victoria, B.C., Canada

Re: Going staggered - opinions wanted

Post by Jono B good »

As previously stated it was a noob question. LSD stands for Limited Slip Differential. From a stand still spot both wheels will spin at the exact same time with no deviation what so ever then unless in cornering thanks for confirming this. I have just recently purchaced a full set used TRX rims with Michilen tires, my spare is mint condition where as the others are more used. I was going to install the less used one on the right side, also when my spare is removed the car will raise itself about 2" on the left side. With 3/4 full tank of gas. The air ride suspension has been removed and she sits on Bilstiens. Thanks for answering my nooby question mate.
Image
~Cirrusblau-Metallic~
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

Jono B good wrote: Sat Jul 28, 2018 9:30 pm I was going to install the less used one on the right side, also when my spare is removed the car will raise itself about 2" on the left side. With 3/4 full tank of gas. The air ride suspension has been removed and she sits on Bilstiens. Thanks for answering my nooby question mate.
Okay, so you were just considering weight distribution as the determining factor then. That's OK, but in my case with a RHD M635CSi, the weight over the right rear wheel would I expect be greater than the left. On the right I have the driver, fuel tank, fuel pump, filler hatch/neck, fuel vapour expansion bottle, Hirschman antenna and the DIN85MF battery and cabling/battery box etc. as well as the warning triangle. I also have the reaction torque of the engine twisting the chassis down on that side too.

On the left is the spare wheel, the jacking equipment and the medical/first aid box. Inside the spare wheel is also the auxiliary fuel canister with another 9 litres of fuel in it. Whilst I don't want to downplay the weight of the spare wheel, I don't think it's anywhere close to counterbalancing all the stuff on the right hand side.
User avatar
Jono B good
Posts: 188
Joined: Mon Jun 04, 2018 10:33 pm
Location: Victoria, B.C., Canada

Re: Going staggered - opinions wanted

Post by Jono B good »

Thanks for the well thought out answer mate, cheers from Canukistan. :D
Image
~Cirrusblau-Metallic~
User avatar
Da_Hose
Platinum Member
Platinum Member
Posts: 3236
Joined: Fri Mar 07, 2008 8:15 am
Location: Santa Ana, CA.

Re: Going staggered - opinions wanted

Post by Da_Hose »

Back in the day, Rug Cunningham used a TRX shod M6, and beat tons of performance cars with major staggered setups (Panera, 911, and others) in the Carrera Panamerica. My M6 came with staggered wheels and a set of 17's. I had planned on switching to the 17's, but the staggered look has grown on me. I did eventually learn that with 245's on the rear, stomping the throttle in the wet would break the rear loose. With 275's, no more breaking loose. So I do believe traction is improved by the stagger, which will also benefit corner exit speeds. So I don't think it's about how much power you have on tap, but how you drive. Low HP cars can blow the doors off bigger competition with balanced suspension, great brakes, and wide/sticky tires, because the driver knows how to use what he/she has got.

Jose
1987 M6 - My dream car
User avatar
DRPM635CSi
Posts: 280
Joined: Thu Jul 09, 2015 6:50 am
Location: Perth, Australia
Contact:

Re: Going staggered - opinions wanted

Post by DRPM635CSi »

Da_Hose wrote: Mon Jul 30, 2018 5:24 am Back in the day, Rug Cunningham used a TRX shod M6, and beat tons of performance cars with major staggered setups (Panera, 911, and others) in the Carrera Panamerica.
He did too. I've just found my copy of the video of that called '89 LaCarrera Panamericana with Rugs Cunningham.

Any interest in me ripping it and encoding to MP4 for sharing? It's a pretty cool early racecam video of a US M6 going stupidly fast for long, long distances in the desert.
User avatar
hornhospital
Platinum Member
Platinum Member
Posts: 2931
Joined: Sun Jul 11, 2010 6:46 pm
Location: Silverhill, AL
Contact:

Re: Going staggered - opinions wanted

Post by hornhospital »

The whole video is available on YouTube, here:

https://www.youtube.com/watch?v=e5YxcDAB3JE

The language is a bit raw towards the end. :oops:

It's 1:06:14 long, posted by our own tschultz. =D>
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
User avatar
tschultz
Posts: 2515
Joined: Wed Jul 07, 2010 10:54 pm
Location: Colorado
Contact:

Re: Going staggered - opinions wanted

Post by tschultz »

IMO, square setup is the way to go for performance and wear. Allows your to change side to side, get 4 of the same tires, and swap around if wear isn't quite even. Just select a better compound tire and keep things simple with a square wheel setup.
http://www.Drive4Corners.com
Image
'79 635CSi Revival
'80 635CSi
'83 633CSi Callaway Turbo continued as 1988 535is Turbo
SOLD: '81 635CSi/A
User avatar
Jono B good
Posts: 188
Joined: Mon Jun 04, 2018 10:33 pm
Location: Victoria, B.C., Canada

Re: Going staggered - opinions wanted

Post by Jono B good »

Watching the vid now thanks 8)
Image
~Cirrusblau-Metallic~
User avatar
Jono B good
Posts: 188
Joined: Mon Jun 04, 2018 10:33 pm
Location: Victoria, B.C., Canada

Re: Going staggered - opinions wanted

Post by Jono B good »

DRPM635CSi wrote: Mon Jul 30, 2018 10:31 am
Da_Hose wrote: Mon Jul 30, 2018 5:24 am Back in the day, Rug Cunningham used a TRX shod M6, and beat tons of performance cars with major staggered setups (Panera, 911, and others) in the Carrera Panamerica.
He did too. I've just found my copy of the video of that called '89 LaCarrera Panamericana with Rugs Cunningham.

Any interest in me ripping it and encoding to MP4 for sharing? It's a pretty cool early racecam video of a US M6 going stupidly fast for long, long distances in the desert.
I am really enjoying this vid Thank you all for sharing this. VERY VERY COOL!!!! =D>

favorite quotes from Alan the co pilot;

"Rug how the hell you talk me into this SHIT!"

"It's Miller time!"

"Man I need a drink!.. I'm sorry!"

"What the *uck is that!?"

"Our speedometer is just *ucking burried, we don't know how fast we're going!"

"I'm done...I'm *unking done! I'll never do this again!"
Image
~Cirrusblau-Metallic~
Post Reply