Hey guys,

I'll soon be replacing the stock FE1 front spring on my '96CE with a 1990 FE1 spring that has been fitted with the poly shim lowering kit. When I do the spring & lowering, I'm going to replace shocks all around as well. I'm pretty sure I want to go with new Bilsteins as my replacements, I just don't know which ones. Having my current ones revalved is not really an option I'm interested in, so help me choose the new ones that are right for me.

All in all I want to stiffen the ride quite a bit over the super soft '96 FE1 I have now. Ride comfort is not nearly as important to me as performance & not bottoming out after the lowering (although I don't want a kidney bruising ride like the early C4 Z51s). As far as performance goes I want stiff, but not so stiff as to skip all over a bumpy curve (of which we have plenty around here), that's why I plan to keep the '96 FE1 spring in the rear. I will not be autocrossing this car, but want it to stick like glue during spirited driving on roads in varoius conditions.

So here are my questions:

1.) When I look in Eckler's I see Bilstein shocks for various C4 years in front & back, Z51 & not. What is the difference in them.... is it size, or length, or valving that is setup for the specific year's spring rate? :confused:

2.) In Eckler's I also see the "Bilstein autocross shock". What is this shock all about? Is it alot more stiff than the Z51 shock? Is it way to stiff for me? :confused:

3.) In general what do you guys think will be the best shock for my setup & what I'm looking to get out of it? :confused:

4.) Is it okay, or ever benificial to run different shocks on the front & back (to match the stiffer vs softer springs)? :confused:

I know, I know.... to many questions, but I need someone to support my habit! :D


BTW, if it matters the car has 57,000 miles on it & is stock.

Thanks,
David




[Modified by DCP, 12:56 PM 1/26/2003]

 

When you see in Ecklers that something is made for Z51 cars, its just a different valving for shocks. Z51 shocks will be stiffer, and wont give a good ride.

The AutoX shock is even stiffer, you dont want that unless this is a real autox car.

You can run stiffer shocks front/back, but i wouldnt. If it was a drag car, you might want the stiffer shocks in rear to keep the rear from squatting as much.

I think youre best off with the Bilsteins, either new or revalved.

 

i've said this before, not sure anyone understood...

the big problem is lack of bump travel with a stock shock configuration. after modifying bumpstops and juggling spacers to gain more bump travel, my car rides extremely well with 1125#/450# f/r, and '96-specific bilstein "sports." without any bump travel mods, i thought it was unbearably stiff for a daily driver. now it's better damped than when stock, but not really a worse ride. (but much better handling/control, of course.)

in other words, i recommend the sports as a minimum. i did have Z51 versions on the car for a few hundred miles, but found them to be underdamped. (i still have the fronts for sale, if you're interested.)

btw, i don't know if this is true, but i was told by 2 sources (one of them bilstein) that the '96-specific sports have more rebound damping than '89-up sports. not less.

yymv.

 

So what are are "bumpstops" & why are they so important?

Are you guys saying the difference between the years is revalving to match the springs?

So far I have one opinion that "sports" (which I assume is the same as the "autocross Bilsteins" in Eckler's) would be way too stiff for my setup & what I'm looking to get out of it, & another opinion that they should be the minimum. :skep: Please keep the opinions coming I'm iterested in the differing views!

What about different shocks on front & back?

Has anyone else heard that '96 Z51 Bilsteins are the most dampening (stiffest) one's except for the autocross/sport specific versions?


Thanks for the info so far! :thumbs:


David


[Modified by DCP, 6:26 PM 1/26/2003]


[Modified by DCP, 6:27 PM 1/26/2003]

 

Hey Vader,

I just reread your post & I see that you addressed my question of different shocks in front & back. But I was actually thinking of the stiffer (autoX) shocks for more dampening in front to compensate for the higher spring rate of the 1990 spring & to help keep me from bottoming out after the lowering. And maybe softer ones in back (like the Z51) to keep the ride bareable & allow the wheels to stay in contact with the road over bumps. I just don't know if this is sound logic or if there are reasons not to do it this way. :confused:


Anyone??


David


[Modified by DCP, 6:29 PM 1/26/2003]

 

The 96 pictured here was ordered specifically with the Z51. I love it. I have driven both the FE1 and the adjustable suspended 96s extensively. It (Z51) just seems like a Corvette feel.

When I go to replace anything it will be as close to Z51 that is available. It only has 27,000 miles now and still rides like when new.

 

TTT

 

You can do it that way, but know that your ride quality is gonna diminish if you put the AutoX shocks on front and Z51 in rear. It wont drop as much as if you went with Z51 springs, but youll notice it.

Try it out and tell us if you like it, thats all i can tell you.

 

Not to divert the meaning of this thread from the original poster... But...

Vader ... Does this mean that in your opinion my stock Z51 outfitted coupe sits lower than a non-Z51 optioned coupe of the same year (1996) ???

THANKS!!!

 

96TorchRedCoupe,

I read what Vader said to mean the quality of the ride would "drop", not the car's hight. But I could be wrong. :skep:


Come on guys, anybody else have any input? Has anyone actually tried the softer spring and shocks in the back first hand?


David

 

:nonod: I didnt say anything about ride height. Stiffer springs will let you lower your car though, that kinda goes hand in hand. You want stiffer springs to keep the car from bottoming out if its been lowered, but shocks also play a role there too.

 

Come on guys, I still have some unanswered questions hanging. I know someone in this awesome knowledgebase has to nknoe the answers! I'm still interested multiple peoples' opinions & experiences.

This is my last TTT.

Thanks,
David

 

at one point i had the aforementioned 1125# front spring, with the stock '96 FE1 rear spring. while it understeered crazily in autoxing, the street ride was virtually indistinguishable from stock. this was with bilstein sports all around (which may not be the "auto-x" shocks you mention).

that was my original point, that if you're worried about ride, the sports and even stiff springs won't hurt you, the lack of bump travel will. without enough bump travel, the chassis and tires become the springs.

also, comparing Z51 to sports, in terms of ride, i could barely feel the difference. the Z51 shocks seemed a bit harsher, like they had more compression damping. the sports seem soft on compression, but firmer on rebound. the car feels more controlled at high speeds, even over bumps and big whoops in the road. it's very impressive.

on eckler's "auto-x" shocks, you need to find out what those are. they might be like VBP's "xtreme" shocks, in which case they're significantly stiffer, in both directions, than the "sports."

lastly, the shock mainly controls the sprung and unsprung weight. i believe the damping should be dictated more by those than by spring rate, although (obviously) a much higher rate spring should mean more rebound and less compression. still, i don't feel mixing shocks f to r is a very good idea. you can create transient handling problems.

does that answer?

 

It sounds like what you're planning is going to give the car quite a bit of understeer. If you want stiffer, you'll need to do both ends.

The spring stiffness is the primary control of the overall stiffness of the suspension and whether the car will under or over steer. Stiffer shocks will not change this except during the very beginning of the turn. Stiffer shocks will make the car settle into the turn slower. Softer shocks will make it settle in faster. Softer shocks make the car more twitchy and snappy... which can cause the car to snap turn and slide sideways if you go too far.

Also, at the extremes over or under shocking will prevent the suspension from moving properly... bouncing is it's totally undershocked, for instance.

That's only a bit of the basics of suspension setting. Unless you really want to get into it hardcore, you should probably get a whole kit of some sort where all of this has been worked out in advance by experts.

I also have the 'soft' (funny definition of soft, really) '96 FE1 suspension. The car handles very nice. I really don't feel a need to stiffen it. Especially when I'm pulling a hard turn and run over some bumpy/uneven road sections and think... hmmm... a stiffer suspension right there would have skittered me into that concrete retainer...

If I did want to stiffen my suspension, I'm thinking thicker swaybars would be a good method. I have often liked the handling characteristics of softer springs with harder sway bars.

- Skant

 

Thanks for everyone's input!


David