|
|
|
|
|
|
BMW Garage | BMW Meets | Register | Search | Today's Posts | Mark Forums Read |
|
BMW 3-Series (E90 E92) Forum
>
Coilovers - Front or Rear Higher?
|
|
02-01-2013, 04:57 AM | #1 |
Colonel
547
Rep 2,590
Posts |
Coilovers - Front or Rear Higher?
I've been reading like crazy about ride heights recently and wanted to see if people biased their ride height or kept it square. People say you don't want a take because of nose dive on braking but isn't our brake system rear biased hence that's why our rear wear so much quicker?
So what's everyone's opinion I'm finding so many conflicting things online. Thanks |
02-01-2013, 04:08 PM | #3 |
Colonel
547
Rep 2,590
Posts |
|
Appreciate
0
|
02-02-2013, 08:57 PM | #5 |
Lieutenant General
2280
Rep 12,565
Posts
Drives: Z4 M, X5, GX460
Join Date: Apr 2008
Location: CT
iTrader: (99)
Garage List F15 X5 xDrive35i [8.75]
E86 Z4 M [10.00] F10 550i (Retired) [9.17] F25 X3 xDrive35i (R ... [9.43] E82 135is (Retired) [9.50] E85 Z4 M (Retired) [9.41] E90 328i xDrive (Re ... [9.25] E86 Z4 3.0si (Retired) [9.20] |
Yea ignore the guy who has proven history building successful race cars lol. Perhaps we should survey the experts here with highest post counts.
OP if you're going to do this right and get a corner balance prior to alignment, the heights of all 4 corners will change anyway. Set it to what you like, looks good and is practical enough to get by. Racers will tell you rake, as long as not aggressive, won't make a huge impact. Getting it balanced is where it's at. |
Appreciate
0
|
02-03-2013, 08:36 AM | #6 | ||
Lieutenant General
2280
Rep 12,565
Posts
Drives: Z4 M, X5, GX460
Join Date: Apr 2008
Location: CT
iTrader: (99)
Garage List F15 X5 xDrive35i [8.75]
E86 Z4 M [10.00] F10 550i (Retired) [9.17] F25 X3 xDrive35i (R ... [9.43] E82 135is (Retired) [9.50] E85 Z4 M (Retired) [9.41] E90 328i xDrive (Re ... [9.25] E86 Z4 3.0si (Retired) [9.20] |
Quote:
Quote:
OP asked about dynamic weight shifting and brake bias and TCK addressed just that. However your opinion of what looks cool is about as least technical as it can get and you answered a question nobody asked. Instead of advising others to consider where others are coming from, you should simply learn to read; the question was right there to begin with. Last edited by 3002 tii; 02-03-2013 at 08:43 AM.. |
||
Appreciate
0
|
02-03-2013, 10:02 AM | #7 | |
Colonel
547
Rep 2,590
Posts |
Quote:
|
|
Appreciate
0
|
02-03-2013, 10:22 AM | #8 |
Captain
62
Rep 788
Posts |
From my personal experience on track with my xi I noticed that when I had front lower then rear the car didn't turn as well on those slow tight turns. But was great on higher speed turns. I then raised the front and turned much better. Im currently still experimenting but I have the front at 3/4" gap from fender to tire and rear at 1/2"
I'm considering raising the suspension about 1/4" more front and rear
__________________
JB4 Trebila tuned cp-e IC AMS exhaust BMS DCI AR DP's METH RB TURBO
19" VMR VB3 Stoptech BBK TC KLINE VORSHLAG SPEC STG 3 OSS design |
Appreciate
0
|
02-03-2013, 10:48 AM | #9 |
Colonel
547
Rep 2,590
Posts |
Nice, thanks Chris, so a slight negative rake, that's what I'm planning on going with. One thing us XI guys never talked bout was roll center correction.
Our control arms are probably way off or will it be soemwhat similar to the i guys with the roll angle. |
Appreciate
0
|
02-03-2013, 10:52 AM | #10 |
Captain
62
Rep 788
Posts |
I'm thinking of upgrading my front sway bar end links with the adjustable ones from HP autowerks. Cause with all that drop up front (especially on an xi= ~2.5inch drop) I'm sure something went wrong there....question is do they fit on xi ....Harold??
__________________
JB4 Trebila tuned cp-e IC AMS exhaust BMS DCI AR DP's METH RB TURBO
19" VMR VB3 Stoptech BBK TC KLINE VORSHLAG SPEC STG 3 OSS design |
Appreciate
0
|
02-03-2013, 11:04 AM | #11 | |
Colonel
547
Rep 2,590
Posts |
Quote:
What I'm worried about now is the angle of the control arms since they're suppose to be parallel with the ground when the car is under load. But with lowering the car so much, I'm wondering if our control arms are aiming upwards which is a big no no in terms or body roll. |
|
Appreciate
0
|
02-03-2013, 07:52 PM | #12 | |
Lieutenant General
2280
Rep 12,565
Posts
Drives: Z4 M, X5, GX460
Join Date: Apr 2008
Location: CT
iTrader: (99)
Garage List F15 X5 xDrive35i [8.75]
E86 Z4 M [10.00] F10 550i (Retired) [9.17] F25 X3 xDrive35i (R ... [9.43] E82 135is (Retired) [9.50] E85 Z4 M (Retired) [9.41] E90 328i xDrive (Re ... [9.25] E86 Z4 3.0si (Retired) [9.20] |
Quote:
But I agree with your intuition on the more rake you have, the more the car would understeer as it would tend to nose dive more. I'll let the xi owners chime in but is the car's weight distribution any different than a non-xi model? If not, I would imagine whatever works on a rwd should work for xi. If the xi is more front heavy, then you probably want to go with less rake. But like I said end of day, if you're willing to spend the $$$, a corner balance would yield the appropriate height for best handling (ie it'll take the guesswork out of how to set the rake). Set the overall height to what you like, and the corner balance would then tweak each corner separately (and you may see variances of up to 1/2" between corners). |
|
Appreciate
0
|
02-04-2013, 08:37 AM | #13 | |||||
45
Rep 345
Posts
Drives: Many BMW's & Porsche's
Join Date: Mar 2012
Location: Columbus, OH & Santa Barbara, CA
|
Quote:
Quote:
Quote:
Quote:
Quote:
First, let's determine where we are taking ride height measurements from. We measure from the rocker panel to the ground, not from the fender. So, at the very front of the rocker panel just where the front wheel well meets the rocker is where we take the front measurement. Then, we take the rear measurement where the rear wheel well and the rocker meet. This may add to the confusion, as we all may be picturing ride heights based on where we measure. OP, your question seemed more like a 'performance' or 'technical' question as opposed to aesthetics. DSC_OFF is correct (thanks for the backing, btw) that we have done extensive testing on the street and on the track, and this is how we recommend you set your ride height if you want your car to perform. We set our cars up for function, not form. If you are looking for a 'stance' look, I have nothing more to offer, but if you want the car to function and perform well, then set the front ride height where you want, and then raise the rear 3/4" higher than the front. That is your base setting, and then you can corner balance from there. You mentioned you don't want your car to 'nose dive' under braking......how hard are you braking on the street? That question just seemed more like a track related question Just so you are aware, the car will actually understeer more as you lower the rear end, until you hit the bump stops. Once you hit the bump stops in the rear the car will oversteer again. So as you raise the rear end, the car will want to oversteer more and understeer less. This set-up will be the same between an xi and non-xi, it does not change. If you want your car to 'perform' on the street and track, this is the race/street proven set-up (assuming your are running the proper suspension and spring rates) based on the hours and hours of testing that we have done with our E90 both on the track and off. The simple answer was 3/4" rake, but hopefully this explanation helps. If you have any more questions, please let me know |
|||||
Appreciate
0
|
02-04-2013, 11:17 AM | #14 | |
Lieutenant General
2280
Rep 12,565
Posts
Drives: Z4 M, X5, GX460
Join Date: Apr 2008
Location: CT
iTrader: (99)
Garage List F15 X5 xDrive35i [8.75]
E86 Z4 M [10.00] F10 550i (Retired) [9.17] F25 X3 xDrive35i (R ... [9.43] E82 135is (Retired) [9.50] E85 Z4 M (Retired) [9.41] E90 328i xDrive (Re ... [9.25] E86 Z4 3.0si (Retired) [9.20] |
Quote:
Btw I love how the kid deleted his posts. What's even more funny is he sent me a PM with a big F U |
|
Appreciate
0
|
02-04-2013, 11:18 AM | #15 | |
DIYER
614
Rep 5,521
Posts |
Quote:
__________________
JB4 G5, Stage 3 LPFP, Stage 2 MOTIV PI, VM 6466 ST, Custom OCC W/ SS lines, ER FMIC, ER CP W/HKS BOV, M3 control arms, M3 guide rods, M3 upper links, M3 front & rear sway-bars, HPA rear toe arms, Wavetrac LSD, HPF Gen 2, DEFIV kit, KW clubsport, Delrin solid SF bushings, stoptech rotors, Rogue Tranny Mounts, 1M bumper, M3 CF hood, M3 fenders, M3 OEM sideskirts, Mtech rear bumper, CSL trunk, MORR VS8.2 rims 245/295
|
|
Appreciate
0
|
02-04-2013, 12:33 PM | #16 | ||
45
Rep 345
Posts
Drives: Many BMW's & Porsche's
Join Date: Mar 2012
Location: Columbus, OH & Santa Barbara, CA
|
Quote:
Quote:
What's nice is that some tape measures will list on the side how 'tall' they are so you can just set it up right and pull the tape out until it hits the rocker. Add the measurement of the tape to the 'height' of the tape measure tool and you are good to go |
||
Appreciate
0
|
02-04-2013, 03:49 PM | #17 | |
Colonel
547
Rep 2,590
Posts |
Quote:
Also, the weight differential is about 215lbs more upfront on the xi so about 53/47 weight distribution. |
|
Appreciate
0
|
Bookmarks |
Thread Tools | Search this Thread |
|
|