Still not happy with suspension...

[bwh13]

The S52 equipped '88 is now riding on the H&R Sport springs with the Bilstein Sports.

While the ride is somewhat better than it was with the Eibach's, it's not really close to the way I want it.

I really want a setup that absorbs the sharp edge bumps like manhole covers that are 1" below the pavement level. I don't mind a good 'thump' going over those, but this setup is more like a 'whack'.

Do I have to go with a coil-over design to get compliance AND control? To be honest if I have to put the car back to the stock ride height to get enough shock travel to give me the ride I want I'll do it.

I really thought there would be more options than what I'm seeing out there...

Does anyone make higher rate springs that are close to the stock length?

[whiltebeitel]

FWIW, note this is in an E36 M3, going from stock to AST 4100's made a really big difference in the handling of my roommate's car, and the ride was just as good as stock when it was "full soft." Elephant Motorsports has a GB on full kits for the E30.

[bwh13]

Thanks, I actually called the AST US distributor a few weeks ago to ask about the kit for the E30.

I might just have to bite the bullet and pony up the $ to get the ride I want.

[jlevie]

To gain handling, you have to sacrifice ride quality. If you really want a stock feel over bumps you'd need to go back to stock spings and shocks.

That said, I'd hazard a guess that it is the Bilstien sport shocks that are at the heart of what you don't like about the suspension. Koni Sport Adjustables set 1/2 to 1 turn from full soft will probably be a more civilized ride. Going to coil overs would be going in the wrong direction.

[bwh13]

Yes I'm beginning to think you are right on the shocks.

They feel way too stiff on compression compared to what I am looking for.

I'll have to admit I didn't anticipate having this much difficulty finding the ride I wanted, and even though I started out building the car for track days, I still would like to drive it around town and not have my teeth rattled.

I'll have to look into sending them to Bilstein to see if they can take out some of the high speed damping. If they can't do that then I'll have to look into replacing them with some Koni SA's.

[sharky]

I just went from bilstein/h&r sports with stock bushings in good shape to Bilsteins w/ GC conversion on 440f/650r and powerflex street bushings everywhere. My ride now is much better than the previous. Expansion joints used to give me like a sharp crack and shake the whole car, now its a dull thud and it is smoother and better planted. Odd how it worked but it is definetly a smoother ride, even the GF commented on it.

[JeffRR]

Your bottoming,
Fixes:
1.) increase ride height
2.) increase spring rate
3.) increase compression damping (give the Bilstein guys in Poway, CA a call for a revalve)

[RyanZ06]

To gain handling, you have to sacrifice ride quality. If you really want a stock feel over bumps you'd need to go back to stock spings and shocks.

That said, I'd hazard a guess that it is the Bilstien sport shocks that are at the heart of what you don't like about the suspension. Koni Sport Adjustables set 1/2 to 1 turn from full soft will probably be a more civilized ride. Going to coil overs would be going in the wrong direction.

I dont agree. Have you ever used a high end damper ? (JRZ, Moton, SACHS, Penske)

[jlevie]

I've driven race cars with high end shocks. But those, because of the high spring rates, are a lot harsher than a street car. I can't imagine anyone putting that class of shocks on a street car, but if one did you could tune the shocks to give a pretty civilized ride provided you didn't go crazy with the springs. But even then it isn't going to be comparable to the OE springs & shocks.

[2002maniac]

I think the problem is the shocks. Bilstein uses an extremely stiff high speed damping to prevent bottoming out. I think you should try konis.

Hopefully Jay from GC will chime in.

[Wh33lhop]

Sounds to me like you're bottoming out. Normal damping generally doesn't make a "thwack." Not damping that isn't really firm.

[bwh13]

I don't know if the front shocks are bottoming out, although the rear does the same type and severity of noise and I know they are not bottoming out.

I suspect it is a combination of heavier engine, spring rate and the compression damping being too high for the level of comfort I am looking for. The H&R's are rated at 180 lbs/inch front and 380 lbs/inch rear from what I could find.

I have contacted a few companiies that make coil springs and asked about custom ones with higher rates to compensate for the heavier S52 engine, something in the range of 300f 450r with a 1" drop. If they don't cost an arm and a leg I'll try that along with the revalve of the Bilsteins.

[Hellabad]

I don't know if the front shocks are bottoming out, although the rear does the same type and severity of noise and I know they are not bottoming out.

I suspect it is a combination of heavier engine, spring rate and the compression damping being too high for the level of comfort I am looking for. The H&R's are rated at 180 lbs/inch front and 380 lbs/inch rear from what I could find.

I have contacted a few companiies that make coil springs and asked about custom ones with higher rates to compensate for the heavier S52 engine, something in the range of 300f 450r with a 1" drop. If they don't cost an arm and a leg I'll try that along with the revalve of the Bilsteins.

check your PM

Jay from GC

[2002maniac]

check your PM

Jay from GC

got anything to share with the rest of us? :)

[Hellabad]

got anything to share with the rest of us? :)

I just had to talk to the guy "in person" to cut through the layers of assumptions, great ideas, bad ideas, right info and wrong info, so bad info doesnt get regurgitated. It benefits all of us eventually.

(This was a "Jay" conversation, not a "Ground Control" conversation. )

Jay