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      05-12-2012, 08:40 PM   #1
sleepless
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Front gets light above 125 MPH

Anyone notice that the front end starts to feel light above 125?

It isn't bad, but I feel the steering gets a bit floaty.

My setup: Stock suspension. 265 RE-11 tires. -2.2 camber
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Last edited by sleepless; 05-14-2012 at 06:17 PM.
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      05-12-2012, 08:45 PM   #2
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Nope mine feels great at 125+. Could it be a road design issue or was it on a flat road?

If you're running zero toe or toe out in front that can cause it to feel floaty/drifty on highways but shouldn't really be speed dependent.
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      05-12-2012, 08:55 PM   #3
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It's a guess, but I would assume that increased front negative camber such as -2.2 increases cornering performance at the expense of straight-line stability or "plantedness" since the car is riding up on the inside edges of the tires. And I also seem to recall that increasing front negative camber causes a corresponding change in toe to an outward direction, so with changing your camber you need a true alignment done to reset the amount of toe to baseline or where you want it. As said above, front toe out would certainly cause a wandering front end.
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      05-12-2012, 09:19 PM   #4
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It isn't wandering. The the steering effort just feels a lot lighter and imperfections in the road are transmitted more intensely.
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      05-12-2012, 09:36 PM   #5
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i havent had that sensation on the track but as said it may be the camber. im stock and feels good up to 140 at PR.
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      05-12-2012, 09:54 PM   #6
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Quote:
Originally Posted by sleepless View Post
It isn't wandering. The the steering effort just feels a lot lighter and imperfections in the road are transmitted more intensely.
Both of those things happen when you go faster..sorry to sound like a smartass.
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      05-12-2012, 11:29 PM   #7
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Quote:
Originally Posted by bigjae1976 View Post
Both of those things happen when you go faster..sorry to sound like a smartass.
I understand, but, I've driven a lot of cars at the track and haven't felt this sensation before. At first I thought it might be the Servotronic steering but I tried it both on and off with no noticeable difference. I've driven the M3 only at The Ridge so it will be interesting how it feels at another track. Maybe it is the surface. I'll know in a bit over week when I get drive at one of my fave tracks, Thunderhill, and where I've drive a wide variety of cars for a good comparison.

Anyway, it seems no one else has felt what I'm feeling. It is minor, but I still wanted to see if this was a common thing with the E9X.

Thanks.
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      05-12-2012, 11:41 PM   #8
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Quote:
Originally Posted by sleepless View Post
I understand, but, I've driven a lot of cars at the track and haven't felt this sensation before. At first I thought it might be the Servotronic steering but I tried it both on and off with no noticeable difference. I've driven the M3 only at The Ridge so it will be interesting how it feels at another track. Maybe it is the surface. I'll know in a bit over week when I get drive at one of my fave tracks, Thunderhill, and where I've drive a wide variety of cars for a good comparison.

Anyway, it seems no one else has felt what I'm feeling. It is minor, but I still wanted to see if this was a common thing with the E9X.

Thanks.
On the autobahn, I did some 160+ MPH runs on a Sun morning. The car definitely felt light as it got closer to the limiter.
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      05-13-2012, 10:47 AM   #9
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I was feeling it at the end back straight at VIR. I am running stock setup except 265/285 staggered APEX wheels on NT01s. I played with tire pressure but did not help.

Will a front diffuser help or is that just for looks?
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      05-13-2012, 10:52 AM   #10
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Quote:
Originally Posted by kartracer12 View Post
I was feeling it at the end back straight at VIR. I am running stock setup except 265/285 staggered APEX wheels on NT01s. I played with tire pressure but did not help.

Will a front diffuser help or is that just for looks?
A splitter will help. Some of the aftermarket front lips look like they would be effective, you just need a sealed splitter across the whole bottom of the bumper. The GT4 style lip would definitely help but is $$. 3d carbon's look effective as well. Many of the lips are just for looks though.
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      05-13-2012, 12:15 PM   #11
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Quote:
Originally Posted by sleepless View Post
I understand, but, I've driven a lot of cars at the track and haven't felt this sensation before. At first I thought it might be the Servotronic steering but I tried it both on and off with no noticeable difference. I've driven the M3 only at The Ridge so it will be interesting how it feels at another track. Maybe it is the surface. I'll know in a bit over week when I get drive at one of my fave tracks, Thunderhill, and where I've drive a wide variety of cars for a good comparison.

Anyway, it seems no one else has felt what I'm feeling. It is minor, but I still wanted to see if this was a common thing with the E9X.

Thanks.
I am not sure you can switch Servotronic off. I believe it is always on. You can just vary the steering effort.

I've always found the M3 very well planted at speeds above 125mph.
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      05-13-2012, 01:03 PM   #12
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Quote:
Originally Posted by bigjae1976 View Post
Both of those things happen when you go faster..sorry to sound like a smartass.
LOL.

That is what I was thinking. Not trying to be a dick either ; )

To the OP - at those speeds, a front lip is going to really have an impact...many great options out there also.
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      05-13-2012, 01:05 PM   #13
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Quote:
Originally Posted by Porschefile View Post
A splitter will help. Some of the aftermarket front lips look like they would be effective, you just need a sealed splitter across the whole bottom of the bumper. The GT4 style lip would definitely help but is $$. 3d carbon's look effective as well. Many of the lips are just for looks though.
iND has a great recreation of the M3 GTS lip.

Ring-werks just released a lip I like as well.

...just a couple more options.
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      05-13-2012, 02:08 PM   #14
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Quote:
Originally Posted by CanAutM3 View Post
I am not sure you can switch Servotronic off. I believe it is always on. You can just vary the steering effort.
Correct, I used the wrong wording. I meant turn the sport setting on/off.
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      05-13-2012, 02:25 PM   #15
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Quote:
Originally Posted by Singletrack View Post
LOL.

That is what I was thinking. Not trying to be a dick either ; )
Maybe I should have prefaced my question with a bit of a bio so people wouldn't assume I'm a nube...

Been tracking cars for 12 years (started out in a 99 M3), with typically 20 days a year in the advanced groups. My track cars (97 Porsche Turbo, 05 Elise) are currently sidelined waiting for custom engines so am trying out the family car at the track for a bit of change while I wait for the engines to be completed.

My goal is to keep the M3 as stock as possible so have modified only the bits I am sure are needed for my needs; camber plates, brake ducts, square tire setup, track pads and brake fluid.

With these minor mods the cars is quite capable and fun; if not a bit on the drifter side . This odd front lightness feeling is the only thing that seems a little bit of a surprise. But, as I mentioned, I need to drive it at a track that I've driven others cars at. The Ridge just opened this year so haven't driven anything else there.

Thanks
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      05-13-2012, 02:56 PM   #16
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Quote:
Originally Posted by sleepless View Post

With these minor mods the cars is quite capable and fun; if not a bit on the drifter side .
Thanks
Definitely. Coming from a Cayman S and a E36 M3 racecar the E92 is a drift machine. Fun though
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      05-13-2012, 04:56 PM   #17
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Quote:
Originally Posted by Porschefile View Post
A splitter will help. Some of the aftermarket front lips look like they would be effective, you just need a sealed splitter across the whole bottom of the bumper. The GT4 style lip would definitely help but is $$. 3d carbon's look effective as well. Many of the lips are just for looks though.
By doing a front splitter with no corresponding rear aero, won't the rear end get relatively light/squirrelly at high speeds?
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      05-13-2012, 05:04 PM   #18
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yeah if you did a full blown race type splitter. But just a small streetable one should be fine IMO. Usually the aero balance is way off in favor of the rear wing in amateur race cars, it's fine to not have the balance exact.
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      05-13-2012, 09:14 PM   #19
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I would think that the GTS front lip and rear wing would get you close to where you need to be as far as aero. IMO anything else is just guessing. Don't tell me that Vorsteiner or any other company cobbling together CF crap designs and tests their stuff in a wind tunnel to perfect the front/rear downforce balance.

Maybe AC Schnitzer, Alpina and Hamann would be the only ones that would have access to those testing facilities.
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      05-14-2012, 08:29 AM   #20
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Try EDC (if you have it) on the firmest setting.
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      05-14-2012, 09:45 AM   #21
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Quote:
Originally Posted by sleepless View Post
Maybe I should have prefaced my question with a bit of a bio so people wouldn't assume I'm a nube...

Been tracking cars for 12 years (started out in a 99 M3), with typically 20 days a year in the advanced groups. My track cars (97 Porsche Turbo, 05 Elise) are currently sidelined waiting for custom engines so am trying out the family car at the track for a bit of change while I wait for the engines to be completed.

My goal is to keep the M3 as stock as possible so have modified only the bits I am sure are needed for my needs; camber plates, brake ducts, square tire setup, track pads and brake fluid.

With these minor mods the cars is quite capable and fun; if not a bit on the drifter side . This odd front lightness feeling is the only thing that seems a little bit of a surprise. But, as I mentioned, I need to drive it at a track that I've driven others cars at. The Ridge just opened this year so haven't driven anything else there.

Thanks
Roger!

In that case, I would suspect alignment as someone else mentioned. Specifically would make sure you have enough toe in the front to avoid the wandering. I've played with toe on this car, and it definitely feels like the front is "lifting"/wandering at high speed if it is zeroed out...

Good luck!
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      05-15-2012, 11:02 PM   #22
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Quote:
Originally Posted by kartracer12 View Post
I was feeling it at the end back straight at VIR. I am running stock setup except 265/285 staggered APEX wheels on NT01s. I played with tire pressure but did not help.
It's probably just coincidence, but I noticed that you & OP have E90's. Those in disagreement have E92's. Could this possibly be a weakness of the E90?
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