Adding another bump stop

[DeNguyen]

Ok, so i just got a new set of wheels not too long ago 18/19 combo. and i have a rubbing issue when hitting dips on the freeway, and under hard cornering. I have the H&R bilstien suspension combo. I was considering swapping to eibach springs to raise the car back up, but was recently suggested to just add another bump stop to the shock. Supposedly itll keep the suspension from traveling far enough so that the car will rub.

Anyway, the idea sounds promising, but I'm also skeptical about doing this. Supposedly my suspension will be stiffer, but will that be a good thing since the bump stops will not allow my suspension to do what its supposed to do?

Any info would help. Thanx in advace.

 

[nsxtasy]

What size tires are you using? It's possible that your tires are just too big, but you then have an easy solution - just get proper sized tires.

For 18" front wheels, some folks are using 215/35-18 tires, which are already slightly larger than the three stock size front tires. If you are using anything larger than that - either wider treadwidth (e.g. 225) or higher aspect ratio (e.g. 40) then it is the tire size that is causing the rubbing.

Another option is to remove the fender liners, although that exposes some of your body parts to damage from gravel etc.

Are the Bilsteins mounted on the lowering perch? If so, you can add some ride height by moving them to the non-lowering perch.

 

[DeNguyen]

im runnin 225/35's up front. dont really wanna get another set of tires since these are barely a hundred miles old. I'm not sure whether or not the perch is on its lowest setting or not, but i know the rear is not on the low setting.

so exrta bump stop = bad idea ?

 

[ncdogdoc]

The biggest problem is the lowering of ride quality. With an extra bump stop, you will run out of suspension travel even sooner, so many dips and bumps will be fairly jarring. If you pick a fairly soft version, then the abruptness of the stop will be lessened, and the jarring not as bad. Good luck.

 

[NSXDreamer2]

Track experts could confirm that since I'm not one...

But Bump Stop steering is supposingly pretty bad suspension engineering...

 

[nsxtasy]

im runnin 225/35's up front.

That's your problem. The tires are wider than stock AND the outer diameter is larger than stock (4.9 percent larger than '91-93 stock, 2.5 percent larger than '94-01 stock).

If you don't want them to rub, get different size tires...

 

[JPS Europa]

Someone mentioned an effect on bump steer. That will not happen. Bump steer is the change in toe caused by the change in relative geometry of the suspension and steering gear. Using a taller bump stop reduces the effective travel of the suspension and will have the effect of suddenly increasing your spring rate when the stop is contacted. This is OK on a billiard table where the contact takes place once and is fairly gentle. You still have a stable handling platform. Unfortunately, we are driving on uneven surfaces. The front end is going to be jumping around and constantly transitioning between normal handling and extreme understeer and then back. I think that you will hate it.
This technique has been used to good effect in racing however. Way back in 1974 Elliot Forbes Robinson was the Super Vee Champion. His car was a Lola T252 which was something of a flexible flier. While the rest of use were trying to find ways to stiffen the chassis, EFR and company fitted the car with rock hard springs and shocks and softened (took pieces out!) the chassis to achieve some compliance. He turned his car into a big go-kart. Great idea! Won't work in an NSX...

 

[sjs]

I would consider removing the springs and perch, then sliding a spacer ring down the shock before replacing the perch and spring. That will raise the car by the amount of the spacers, but the H&Rs are so low to begin with that you can add 1/2 inch and still be pretty low. That will also allow the Bilstein to operate closer to the middle of their range. As for bump-steer, it is as described by JPS but it does happen to be an issue on the NSX with the H&Rs set at stock perch height because they lower the car so much.

BTW I tried the Bilstein + H&R combo and found it to be significantly under damped. (The Bilsteins are too weak for the springs)

 

[Zishan]

I had the same problem. I have Neuspeed springs and my cars lowered about 2 inches. I also have 18/19 inch wheels with 225/35/18 in front. So, I was rubbing a lot. I ended up buying the Dali Race sway bars and the helped out with 90% of the rubbing issues when I would turn. But I still get some rubbing going up my driveway and on some dips. I'm planning on switching to 215/35/18's on the front and just selling the slightly used 225/35/18's. Gotta do whatcha gotta do!
Regards,
- Z