BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Track / Autocross / Dragstrip / Driving Techniques
 
GetBMWParts
Post Reply
 
Thread Tools Search this Thread
      08-06-2013, 01:05 AM   #1
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

Ride height for street & track?

I'm dropping my EDC car with a spring/sleeve kit (it works with the GC camber plates I already have and was cheap; if unsatisfactory, I'll go coilovers, but brakes killed my mod budget for this year).

Anyway, I've had some trouble finding posts on a good ride height for a tracked, mostly street car. Here's what someone posted for the factory setup on a 2012 M3 E92 ZCP, which seems like a good starting point:

-F 14.2"
-R 14.0"

(I got that from this post: http://www.m3post.com/forums/showpos...80&postcount=7 but now I wonder if I'm reading it correctly... it seems like he means those are stock and then goes on to say how he modified it. So, when he says a R 0.25" rake, does he mean the rear is 0.25" higher than front?)


As for my goals, I know I don't need to lower it, but I have coilovers on my A4. It's not slammed, but dropped a little below the factory S4 ride height. I have grown to love its firm ride and the connected feeling of driving it. I've never liked the M3's ride as much, on any EDC setting. I'm hoping the stiffer springs and a slight drop will help.

BTW, both cars have 18" wheels with 35-aspect tires. It seems like a good track setup, and the streets around here would not be kind to 19" wheels.


Thoughts?
__________________

Last edited by Drifty//; 08-06-2013 at 01:44 AM.
Drifty// is offline   United_States
0
Reply With Quote
      08-06-2013, 01:11 AM   #2
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

BTW, I have a non-ZCP car, so that's why I'm looking to ZCP as a step in the right direction, but still street-friendly.
__________________
Drifty// is offline   United_States
0
Reply With Quote
      08-06-2013, 10:41 PM   #3
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

Well, can anyone at least advise on what amount of rake to use? Do I want higher in the rear? Is 0.25" good?
__________________
Drifty// is offline   United_States
0
Reply With Quote
      09-06-2013, 11:05 PM   #4
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

I noticed this thread, which lists the factory ride height:
E92 M3 Factory Alignment Specifications and Ride Height
I went with a 0.5" drop, in front, which is ~13 mm. So, just a tiny bit lower than ZCP. I'm using a 0.5" rake, so the rear is adjusted accordingly (I'll post that number if I find it). Seems planted on the track, and I really like the way it handles on the street.

I upgraded the front & rear springs to Ground Control's EDC-compatible coilover conversion kit. I think the front spring rate is now 440 pounds (the invoice says something about that). I don't know the rate of the new rear springs. It adds firmness and really helps in corners, but EDC comfort mode is still very compliant (if a bit bouncy).

I'm finally rather pleased with the way my car rides, both street & track (previously, I was not very happy with either). It's still not optimal, but my current thinking is that I'll probably upgrade the rear subframe bushings before doing anything more with springs/dampers/coilovers, if ever.
__________________
Drifty// is offline   United_States
0
Reply With Quote
      09-19-2013, 05:21 PM   #5
spr
Lieutenant
 
Drives: e92 M3
Join Date: Nov 2008
Location: San Diego

Posts: 455
iTrader: (0)

GTS specs:

32 00 Wheel Alignment E92 / M3 GTS
Observe test conditions

FRONT AXLE:
Total toe-in 0 10 8'
Adjustment total toe-in* 0 10 6
Toe difference** single wheel between left/ right max. 12'
Camber (difference between left/right max. 30') -1 10 20
Adjustment camber* -1 10 10
Toe difference angle (difference between left/right max. 30')
- with inner cornering wheel at 20 steering angle -2 02 30'
Castor angle (difference between left/right max. 30')
Front wheel offset 0 15'
Maximum steering angle
- Inner cornering wheel approx.
- Outer cornering wheel approx.
REAR AXLE:
Total toe-in 0 10 6
Adjustment total toe-in* 0 10 6
Camber (difference between left/right max. 30') -200 15
Adjustment camber* -2 00' 10'
Geometrical driving axis 0 12'
*Note: To minimise adjusting errors (measuring inaccuracies), use a narrower tolerance for adjusting toe/camber.
*Note: Toe difference front axle = criterion for steering wheel inclination

31 00 Front axle - ride height E92 / M3 GTS
Ride height in normal position (DIN empty)

Attach tape measure to bottom middle of rim flange and measure to lower edge of wheel arch


Tolerance ride height in
-Normal position +/- 3mm
SERIES
19" wheel rim mm 613


33 00 Rear axle - ride height E92 / M3 GTS
Ride height in normal position (DIN empty)

(attach tape measure to bottom middle of rim flange and measure to lower edge of wheel arch)


Tolerance ride height in
Normal position +/- 3 mm
Difference ride height between left/right in
Normal position +/- 3 mm
Series
19" wheel rim mm 597


31 00 ...
Notes on threaded chassis M3 GTS

The BMW M3 GTS features a threaded chassis with the following range of adjustments:
- Vehicle height
- Camber on front axle
- Rebound/compression stage, shock absorber

This can be used to adjust the chassis to different road profiles and driving styles.
The chassis has two preset setups:
- Road setup = factory setting for operation in traffic
- Racetrack setup = setting for operation on a racetrack only
Important!
For operation in traffic, the factory settings (road setup) must be used!



Note the following procedures for setting the various setups:
• Ride height
• Rebound and compression stage setting

Recommended adjustment values:
Road setup Rebound stage Compression stage Ride level
Front Axle 8 clicks open 5 clicks open 613
Rear axle 9 clicks open 4 clicks open 597
Racetrack setup
Front Axle 8 clicks open 3 clicks open 597
Rear axle 9 clicks open 2 clicks open 585
spr is offline  
0
Reply With Quote
      09-19-2013, 05:37 PM   #6
SlowSaloonM3
Major General
 
SlowSaloonM3's Avatar
 
Drives: m3 saloon in granny mode.
Join Date: Dec 2009
Location: lost angeles

Posts: 6,570
iTrader: (0)

wish someone had a GTS on these boards and would post some actual yumminess.

I would stay stock until full suspension upgrade.
__________________

When is this episode coming?!
My thoughts on M5/6 vs M3/4...i wonder if tuned panamera turbo S owners are laughing at gt3 owners because they have "no chance in a race"
SlowSaloonM3 is offline  
0
Reply With Quote
      09-19-2013, 05:39 PM   #7
spr
Lieutenant
 
Drives: e92 M3
Join Date: Nov 2008
Location: San Diego

Posts: 455
iTrader: (0)

I just posted the exact setup for the GTS dude.
spr is offline  
0
Reply With Quote
      09-20-2013, 09:58 AM   #8
SlowSaloonM3
Major General
 
SlowSaloonM3's Avatar
 
Drives: m3 saloon in granny mode.
Join Date: Dec 2009
Location: lost angeles

Posts: 6,570
iTrader: (0)

Quote:
Originally Posted by spr
I just posted the exact setup for the GTS dude.
Talking about some real pics of their own gts. Not a spec sheet.
__________________

When is this episode coming?!
My thoughts on M5/6 vs M3/4...i wonder if tuned panamera turbo S owners are laughing at gt3 owners because they have "no chance in a race"
SlowSaloonM3 is offline  
0
Reply With Quote
      09-20-2013, 10:14 AM   #9
Billj747
First Lieutenant
 
Billj747's Avatar
 
Drives: Everything
Join Date: Feb 2009
Location: Wellington, FL

Posts: 397
iTrader: (0)

Send a message via AIM to Billj747
Quote:
Originally Posted by pkim1079 View Post
wish someone had a GTS on these boards and would post some actual yumminess.

I would stay stock until full suspension upgrade.
GTS = KW Clubsports with custom valving:

http://www.m3post.com/forums/showthread.php?t=385970
__________________
Billj747 is offline   United_States
0
Reply With Quote
      09-20-2013, 10:20 AM   #10
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,612
iTrader: (5)

i was under the impression that for track use a slightly raised front compared to the rear was needed. need more front travel under braking than rear.
__________________

02 Tiag e46 M3|6MT|GC plates|MCS c.o.|GC bars|GC race control arms|GC bushings & bearings|BW eng. & tran. mounts|subframe kit|BW race shifter|BW Jaffster|Euro header|BW race|K&N c.a.i.|Epic race tune|Rouge pulleys|Seibon CF hood|CSL bumper|ST-40|XR-2|SS lines|half cage|Recaro profi|Profi 2 harness|BMWpedals|BW studs|
1MOREMOD is offline   United_States
0
Reply With Quote
      09-20-2013, 10:56 AM   #11
SlowSaloonM3
Major General
 
SlowSaloonM3's Avatar
 
Drives: m3 saloon in granny mode.
Join Date: Dec 2009
Location: lost angeles

Posts: 6,570
iTrader: (0)

Quote:
Originally Posted by 1MOREMOD
i was under the impression that for track use a slightly raised front compared to the rear was needed. need more front travel under braking than rear.
Isnt the stock setting like that too? My front sits higher than rears but theres still some rake.
__________________

When is this episode coming?!
My thoughts on M5/6 vs M3/4...i wonder if tuned panamera turbo S owners are laughing at gt3 owners because they have "no chance in a race"
SlowSaloonM3 is offline  
0
Reply With Quote
      09-20-2013, 11:16 PM   #12
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

Quote:
Originally Posted by pkim1079 View Post
I would stay stock until full suspension upgrade.
Well, I had stock EDC and really wasn't happy with it on the track. After installing the GC spring & sleeve kit + camber plates, with the ride height and camber settings I mentioned above, I'm very pleased with it on the track, yet it's very usable on the street. Until the EDC dampers need replacement, I don't see any reason for furher upgrades. Even then, there's a 50/50 chance I'll keep the same setup and just buy another set of EDC dampers.
__________________
Drifty// is offline   United_States
0
Reply With Quote
      09-20-2013, 11:23 PM   #13
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,612
iTrader: (5)

Quote:
Originally Posted by Drifty// View Post
Well, I had stock EDC and really wasn't happy with it on the track. After installing the GC spring & sleeve kit + camber plates, with the ride height and camber settings I mentioned above, I'm very pleased with it on the track, yet it's very usable on the street. Until the EDC dampers need replacement, I don't see any reason for furher upgrades. Even then, there's a 50/50 chance I'll keep the same setup and just buy another set of EDC dampers.
stock set up is not nearly firm and precise enough once you get to intermediate. once your that quick the car feels slow and wallowy. i was waiting around for the car to settle into the entry phase of the corner.
__________________

02 Tiag e46 M3|6MT|GC plates|MCS c.o.|GC bars|GC race control arms|GC bushings & bearings|BW eng. & tran. mounts|subframe kit|BW race shifter|BW Jaffster|Euro header|BW race|K&N c.a.i.|Epic race tune|Rouge pulleys|Seibon CF hood|CSL bumper|ST-40|XR-2|SS lines|half cage|Recaro profi|Profi 2 harness|BMWpedals|BW studs|
1MOREMOD is offline   United_States
0
Reply With Quote
      09-21-2013, 11:25 AM   #14
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

Quote:
Originally Posted by 1MOREMOD View Post
stock set up is not nearly firm and precise enough once you get to intermediate. once your that quick the car feels slow and wallowy. i was waiting around for the car to settle into the entry phase of the corner.
What springs were you running? The front springs in my GC kit are 440 pounds/inch. Do you remember what ride height you used?

I'm not claiming this is the ultimate track setup. Just that suspension no longer feels like a glaring weakness. So far, I'm very satisfied with how it feels on the track, and it's still very street-friendly.
__________________
Drifty// is offline   United_States
0
Reply With Quote
      09-21-2013, 12:02 PM   #15
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,612
iTrader: (5)

Quote:
Originally Posted by Drifty// View Post
What springs were you running? The front springs in my GC kit are 440 pounds/inch. Do you remember what ride height you used?

I'm not claiming this is the ultimate track setup. Just that suspension no longer feels like a glaring weakness. So far, I'm very satisfied with how it feels on the track, and it's still very street-friendly.
sorry stock springs and stock edc suspension. so changing to higher rate like that may help for the time being. stock set up is a glaring weakness once you go a little faster. now i am on 700 front and 800 rear.
__________________

02 Tiag e46 M3|6MT|GC plates|MCS c.o.|GC bars|GC race control arms|GC bushings & bearings|BW eng. & tran. mounts|subframe kit|BW race shifter|BW Jaffster|Euro header|BW race|K&N c.a.i.|Epic race tune|Rouge pulleys|Seibon CF hood|CSL bumper|ST-40|XR-2|SS lines|half cage|Recaro profi|Profi 2 harness|BMWpedals|BW studs|
1MOREMOD is offline   United_States
0
Reply With Quote
      09-21-2013, 12:45 PM   #16
KennyPowers
Brigadier General
 
Drives: .....
Join Date: Oct 2010
Location: Gulf Coast

Posts: 3,618
iTrader: (13)

Quote:
Originally Posted by pkim1079 View Post
Isnt the stock setting like that too? My front sits higher than rears but theres still some rake.
yes stock is like that and rake is due to the taller rear tire compared to the front

conceptually the front needing to be a bit higher than the rear makes sense to me.
KennyPowers is offline  
0
Reply With Quote
      09-21-2013, 06:03 PM   #17
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

Quote:
Originally Posted by KennyPowers View Post
conceptually the front needing to be a bit higher than the rear makes sense to me.
On the track? Seriously?

All three shops I've been to since installing these springs have experience in preparing cars for the track, and two of them have their own race teams. They all agreed with the idea of a forward rake (not sure if that's the right term, but I mean the rear of the chassis sitting higher off the ground than the front). The rationale for this is to create more aerodynamic downforce. And note that this is measured between the chassis and ground - not at the fenders.

And I honestly don't see why you'd need or want more suspension travel for braking. I can't see when brake dive is ever a good thing. Maybe in the snow or rain, but not in typical track conditions.
__________________

Last edited by Drifty//; 09-21-2013 at 06:10 PM.
Drifty// is offline   United_States
0
Reply With Quote
      09-21-2013, 06:06 PM   #18
Drifty//
First Lieutenant
 
Drives: A4 quattro 3.2 MT6; E92 6MT
Join Date: Mar 2012
Location: Boston

Posts: 310
iTrader: (0)

Quote:
Originally Posted by 1MOREMOD View Post
sorry stock springs and stock edc suspension. so changing to higher rate like that may help for the time being.
Okay, so that's where I started, and I can tell you that just installing the Ground Control kit and the ride height adjustment helped immensely. It also included replacement swaybar end links and I think replacement bump stops.

I actually installed the camber plates before the first time on track, so I'm just comparing stock springs/height to the GC springs w/ 0.5" drop.
__________________

Last edited by Drifty//; 09-21-2013 at 06:15 PM.
Drifty// is offline   United_States
0
Reply With Quote
      09-21-2013, 07:44 PM   #19
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,612
iTrader: (5)

Quote:
Originally Posted by Drifty// View Post

And I honestly don't see why you'd need or want more suspension travel for braking. I can't see when brake dive is ever a good thing. Maybe in the snow or rain, but not in typical track conditions.
brake dive isnt a good thing but when you slow down a 3000lb mass weigh will shift forward. its just physics. much of that is reduced with stiffer fronts but it still happens, and once you increase a cars grip with better tires you begin seeing increased braking and more weight shift again.
__________________

02 Tiag e46 M3|6MT|GC plates|MCS c.o.|GC bars|GC race control arms|GC bushings & bearings|BW eng. & tran. mounts|subframe kit|BW race shifter|BW Jaffster|Euro header|BW race|K&N c.a.i.|Epic race tune|Rouge pulleys|Seibon CF hood|CSL bumper|ST-40|XR-2|SS lines|half cage|Recaro profi|Profi 2 harness|BMWpedals|BW studs|
1MOREMOD is offline   United_States
0
Reply With Quote
      09-21-2013, 09:14 PM   #20
bigjae1976
Takes threads off topic...daily
 
bigjae1976's Avatar
 
Drives: 11 E90 M3 Individual
Join Date: Mar 2006
Location: Milwaukee, WI

Posts: 5,236
iTrader: (11)

Garage List
2004 BMW M3  [4.50]
2011 BMW E90 M3  [5.00]
2013 BMW 328i  [5.00]
Quote:
Originally Posted by Drifty// View Post
On the track? Seriously?

All three shops I've been to since installing these springs have experience in preparing cars for the track, and two of them have their own race teams. They all agreed with the idea of a forward rake (not sure if that's the right term, but I mean the rear of the chassis sitting higher off the ground than the front). The rationale for this is to create more aerodynamic downforce. And note that this is measured between the chassis and ground - not at the fenders.

And I honestly don't see why you'd need or want more suspension travel for braking. I can't see when brake dive is ever a good thing. Maybe in the snow or rain, but not in typical track conditions.
You want more suspension travel on the track, period. Running out of suspension travel means you are beyond the capabilities of the suspension to control the car. BMWs are front end heavy (like almost every other front engine sedan) so you need as much travel in the front suspension as possible.

You will find the car will rotate under all conditions much better by keeping the car pretty close to level.

My E46 M3 is pretty close to level and it rotates very well.
__________________


Sponsored by Momentum BMW #593...We Bleed BMW BLUE!
bigjae1976 is offline  
0
Reply With Quote
      09-22-2013, 10:40 AM   #21
KennyPowers
Brigadier General
 
Drives: .....
Join Date: Oct 2010
Location: Gulf Coast

Posts: 3,618
iTrader: (13)

Quote:
Originally Posted by Drifty// View Post
On the track? Seriously?

All three shops I've been to since installing these springs have experience in preparing cars for the track, and two of them have their own race teams. They all agreed with the idea of a forward rake (not sure if that's the right term, but I mean the rear of the chassis sitting higher off the ground than the front). The rationale for this is to create more aerodynamic downforce. And note that this is measured between the chassis and ground - not at the fenders.

And I honestly don't see why you'd need or want more suspension travel for braking. I can't see when brake dive is ever a good thing. Maybe in the snow or rain, but not in typical track conditions.
over-react much?

FYI I said the suspension travel / wheel gap conceptually makes sense to be more in the front than the back. most cars run taller tires in the back vs the front, so the rake is natural. never claimed to be a pro driver or race car specialist.

brake dive isn't a good thing, but it happens on any car.
KennyPowers is offline  
0
Reply With Quote
      09-22-2013, 03:07 PM   #22
Billj747
First Lieutenant
 
Billj747's Avatar
 
Drives: Everything
Join Date: Feb 2009
Location: Wellington, FL

Posts: 397
iTrader: (0)

Send a message via AIM to Billj747
FWIW:

For my 2009 E90 with 19" wheels:

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
245/35-19 3.4in 12.9in 25.8in 80.9in 783 0.0%
265/35-19 3.7in 13.2in 26.3in 82.6in 767 2.1%

= The rear tire is 0.5" larger in diameter than the front (0.25" higher rear ride height due to the larger radius).

I measured my E90 M3 at:

Front Fender (ground to lip): 26 5/8" = 26.625"
Rear Fender (ground to lip): 26 7/16" = 26.438"

Front Framerail (at jack point): 6 3/8" = 6.375"
Rear Framerail (at jack point): 7" = 7"

Thus: The front fender sits a bit higher than the rear (~0.187") while the radius of the front tire is 0.25" less. This visually should look like almost 0.5" (~0.437") of a gap more in the front between the lip of the wheel and the fender than the rear.


Rake:

Measured at the frame rail at the jacking points, the rake is 0.625" with the front of the car lower than the rear. Rake is somewhat arbitrary and what only matters is using the same point when measuring from Car A to Car B, or from setup A to setup B. You can use the fenders as a baseline for rake, but in racing they can be moved and bent so it's not the best place to measure from. At the end of the day, the chassis is nose-down while the fenders are almost even if not slightly nose-up.


I wouldn't call the M3 as "nose-heavy" since its pretty much 50/50 weight distribution. Due to the anti-dive in its suspension geometry, the front does not travel much during braking, especially when you use high spring rates. As long as the front suspension dosn't bottom-out, the front ride height or spring rate of the car does not need to be excessively high.


0.02
__________________
Billj747 is offline   United_States
0
Reply With Quote
Post Reply

Bookmarks

Tags
ride height, track

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 10:04 AM.




m3post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST