[STEye]

I am having an issue where my car is riding on the front bumpstops when autocrossing. Autocross god Mark "The Alien" Daddio, drove my car and notified me of the problem.

Question is, do I: a) Cut the bump stops (as per other people have posted) or b) adjust more preload into the front? Current preload is now set at 2 full turns on the collar after it touches the spring.

[lackskill]

how far from coil bind are you? cutting the bumpstops could do more damage than good if you run out of spring.

[import111]

When your car is jacked up in the air, can you move the springs at all? If you can, you do not have enough pre load and that is why you are hitting the bump stops. I have never hit the bump stops once on my Tein Flex's in the 1 1/2 years I have had them.

[STEye]

Originally Posted by lackskill

how far from coil bind are you? cutting the bumpstops could do more damage than good if you run out of spring.

What is coil bind?

[STEye]

Originally Posted by import111

When your car is jacked up in the air, can you move the springs at all? If you can, you do not have enough pre load and that is why you are hitting the bump stops. I have never hit the bump stops once on my Tein Flex's in the 1 1/2 years I have had them.

When I jack up my car, I can twist the spring ever so slightly if I try really hard. I set my preload to two turns on the collar after it touches the spring, so there is tension, but not to the point where it is impossible to twist the spring.

[import111]

I personally don't think your pre load is tight enough. I turn mine until the spring wont move anymore and then turn 1/2 a turn more.....give or take a little bit to even out all 4 corners of course.

[STEye]

Originally Posted by import111

I personally don't think your pre load is tight enough. I turn mine until the spring wont move anymore and then turn 1/2 a turn more.....give or take a little bit to even out all 4 corners of course.

Do you have an estimate how many turns that would be (after the collar hits the spring?)

[Stee]

When you were describing your problem with terminal oversteer in almost every situation, bumpstop issues did come to mind. That's why I recommended raising the ride height. In the end, I'm glad you were able to get the 'ultimate' opinion on that problem though!!

[STEye]

Dave, WRT my ride height, I think I'm going to raise it up even more.. The general consensus is that the front should be 14" and the rear 13.5".

My only fear with increasing the front preload is that the ride will become even more unbearable than it is now! I can't find any good Tein Flex setup threads.. Anyone know of any that I'm not finding?

[import111]

Nope, I don't have an estimate of how many turns. Sorry. Also, how stiff do you have your struts set to? They recommend not setting them at full soft......and I could see running full soft having the problem of hitting the bump stops as you are. I run 1 click from full stiff always.

[ghostshadow]

general consensus.. well, i'll be nice and say no comment

what does preload have anything to do with how the springs act under compression?

when you hit the front bumpstops you will create infinite springrate and your car will push. there's no way you're hitting the bumpstops in the rear on turn-in to cause snap oversteer. two entirely different issues.

cut the front bumpstops down chris. problem solved. they will not coilbind. raise your rear a hair because you set it on the low side. did daddio loop your car or comment on snap oversteer? i thought it was more of a rear swaybar problem that you addressed after the evo school. and what are your tire pressures? that is another variable.

burkhardt (2x STU national champ) posted some nice nuggets of info on his flex settings.. search for stu-champ or something along those lines.. he is of the go as low as you can school of thought and guess what, it works.

dan

[import111]

Originally Posted by ghostshadow

what does preload have anything to do with how the springs act under compression?

If the pre load is loose, then the strut will be under compression while the car is sitting still, which is not suppose to be the case, and the looser the spring pre load the farther into compression the strut will be, hence hitting bump stops if the pre load is set too loose.

[ghostshadow]

gotcha.. in chris's case, i don't think the lack of preload was to that extreme. worth a shot though

Originally Posted by import111

If the pre load is loose, then the strut will be under compression while the car is sitting still, which is not suppose to be the case, and the looser the spring pre load the farther into compression the strut will be, hence hitting bump stops if the pre load is set too loose.

[STEye]

Originally Posted by ghostshadow

did daddio loop your car or comment on snap oversteer? i thought it was more of a rear swaybar problem that you addressed after the evo school. and what are your tire pressures? that is another variable.

Daddio didn't spin my car, I did though... When I mentioned going back to a stock bar (which I have right now), he was a little hessitant on suggesting that. For the topic of this thread, I wasn't trying to imply that the bumpstop issue was causing the "snappyness" of my car. I have toyed around with rear pressures over the past couple autocrosses. Gone from low to high, I really can't get the optimum pressures. could be just lack of skill.

Originally Posted by ghostshadow

burkhardt (2x STU national champ) posted some nice nuggets of info on his flex settings.. search for stu-champ or something along those lines.. he is of the go as low as you can school of thought and guess what, it works.

If you can find that thread for me, I would appreciate it. I tried looking on here as well as Nasioc.

FYI, my front ride height is about 13.25" and my rear is about 12.75". I noticed that the front right fenderliner is getting rubbed on pretty bad during the turnarounds, where the strut is loaded and hitting minute bumps.

This is what Tein wrote to me regarding trimming the bumpstops:

"We would recommend that you leave the preload at the recommended setting.
However, it is a common practice that consumers are trimming the bump stop
down to 10mm. Although, it is not our recommendation to do so, but it will
help, and we haven't had any complaint on this."