I need help correcting my suspension woes...

[Szalkerous]

Disclaimer...

I know there are quite a few posts here regarding "what do I use" setups, but through all of them I didn't get a strong sense of that the OP was trying to achieve, so I couldn't rely on the commentary.

Currently....

I've noticed whatever suspension monstrosity is on my Z28 causes me the following problems:

• Wiggles ("hard rebounds") out in corners, dives hard on braking, and highway speeds over 110 feel as if I was in a mis-aligned Cadillac.
• Rides harshly, making me suspect someone mismatched the setup
• Odd traction conditions, especially in corners, although this may be a result of a factory LSD on the end of life.
• I can't identify the existing setup as anything special/aftermarket
• Supposedly the suspension is all new as of a year or so ago when I picked the car up.
• It also sits ridiculously high IMO. Eyeballing it with a ruler shows me 3.5" in the rear between the top of the tire to the lip of the fender. Front is 3". Ground clearance on the front center of the bumper at it's lowest point is about 7-7.5".
• The car does not seem to exhibit blown shock symptoms.

What I'm looking for...

I'm looking for a package that will give me "corner carving performance" and high speed (>130 MPH) stability without being a $2,000 bill. Obviously, ride quality is expected to be compromised somewhat in exhange for a firmer ride. I'm the type of driver who gets no greater happiness in life than toss the car down windy backroads and offramps at speed. The car is not currently AutoX'd, but may potentially be at some point if my AWD Subaru SVX gets retired.

I've heard from other car groups that Koni's are great, but yet at the same time some local folks told me Koni yellow's blow out constantly.

I noticed LMPerformance.com has G2 springs, progressive, that are touted as follows:

G2 Super Springs 1.75 Inch Lowering Springs.

The infamous G2 Super Springs are back! Thirty-five years of road race experience bundled up in one nice package. The G2 Super springs are manufactured to LG specs by none other than HyperCo. HyperCo is the worlds leading manufacturer in Custom race springs for NASCAR, Indy, the military and don't forget LGM.

Custom tailored for your f-body and born on the road course, the G2 super springs bring all of our experience into one great spring combination.

Spring rates are 550/180-220 and the springs lower the car approximately 1.75" front & rear. Your results may vary due to vehicle weight.

Shocks recommended for this spring package are Bilstein HD's

Now reading up here, I'm seeing that folks don't like the progressive rates springs, and don't recommend the Bilstein HDs with drop springs.

Any advice/recommendations towards this situation is greatly appreciated!

-Sz

[shady milkman]

talk to strano...he's a sponsor. it largely known that his springs are the best for our cars...i am planning on getting some soon hopefully. shock wise...konis are very solid..alot of people like the qa1 set up also ...but some dont...i would say strano white springs and sin adjustable koni's

[Szalkerous]

talk to strano...he's a sponsor. it largely known that his springs are the best for our cars...i am planning on getting some soon hopefully. shock wise...konis are very solid..alot of people like the qa1 set up also ...but some dont...i would say strano white springs and sin adjustable koni's

I took a look at his website @ www.stranoparts.com. Are the "white" springs the 1.2" drop springs (p/n SP141)?

[shady milkman]

SP141 it is..i always call them white springs...sorry

[Eugenio_SS]

depending on how stiff spring rate you want... if you can live w/ stock spring rates, I'd keep the springs, get Koni SA on all corners... lower car 3/4" due to 2 perch locations + hose-mod in the rear.
So far, only shocks that hit the bank.
Then, I'd get a big front swaybar... 35-36mm and keep stock rear.
Get a good alignment... and that should set you up.

Since your goals are cornering, i'd consider getting a T2R replacing the stock differential... makes a world of difference, allowing to transfer power to the grippy tires, and not letting the inside tire spin. you can always do the T2R @ a later time.

if you can't live with stock spring rates... i'd recommend getting strano springs.

[Sam Strano]

Honestly, most of your complaints are shock related, and not so much the springs. Every symptom you mention there can be laid at the feet of weak shocks even if they don't appear to be blown out or worn. That's kind of like looking at an engine and if you don't see any gaping holes thinking it's in tip-top shape inside.

We offer a variety of handling packages or "HP" kits on our website, and all the parts we sell can be had individually as well. HP3 and HP4 are the biggest sellers. I put all those kits together, and they are the various stages I'd recommend depending on what I find most people are after.

While the stock LSD isn't great, on the street only it's not a problem. But when the car won't take a set, the can and will unload tires suddenly. Unload on under power and you get instant and sudden wheelspin, and usually a snap oversteer to go with it.

Koni's. They don't blow out all the time. I can happen as with any other shock, but I just sold a front set that were over 10 years old, and they worked great (only changed while chasing down what turned out to be a non-shock related issue). Bilstein HD's are not in any way, and never have been in any way suitable for lowered cars. And even if they were, not for springs as heavy as LG's all around, or my front springs. Bilstein's catalog *USED* to say that HD's were not suitable for lowered cars. They just removed that (probably because I'd point it out-a lot). However, anyone with common sense can just look through the catalog and find that Bilstein makes Sport valvings for pretty much any performance car but the Camaro. If HD's were so right, why make Sports? HD's are NOT performance shocks.

[Szalkerous]

Thanks for the in-depth responses.

Suspension - Yeah, I'd prefer something stiffer than stock, and I personally think the ride height is causing a steep center of balance. I think at this point, I may go with SS's "white" springs mated with the koni's (koni makes some great suspension for other cars.... so I believe in this solution). The swaybars are also a concern... I think some of the stock hardware, in particular the trailing arms, have severely worn bushings causing a lot of slop. I may just swap these out as well with what's available at stranoparts.

as for the rear end, I was mulling over doing a complete rear replacement with a strange 12 bolt. (As seen here) but I suppose that's a topic for another thread.....

[Eugenio_SS]

yeah... but when comes time for rear-end... make sure not to make the mistake of getting a straight only performance differential.. that's why i went w/ a 9", so I could get a great cornering diff while being stronger... none were available in a 12-bolt. (Sam helped me w/ that setup too )