ImaRoadDog

Now that the Pfadt/Johnny Oconnell suspension package is no longer available due to their sad demise, I was wondering what people are using for suspension package upgrades to help improve the handling a little. The application is for a 2012 Grand Sport with the base suspension. I need to get just a couple of seconds more out of the car at the track. I am already running Michelin Pilot Sports (which improved the handling quite a bit over the Goodyears), but am still having some body lean and low grip issues on the tighter turns. Brakes are good too, as I almost always out brake the other competitors on the track (I run a time trial series). Any ideas without breaking the bank?

0Anthony @ LGMotorsports

If you just want to do a little bit of a change to the car the Bilstein sport shocks and a set of ZR1 sway bars would be a low buck step up over what you have.

Of course there are always coil overs too

RBbugBITme

I'll probably be putting on low-buck non-coilover single adjustable Penske's when they're available.

jcosta79

LG Motorsports G2 Coilovers

/thread

el es tu

Id do the front ZR1 swaybar or go with a van steel or strano parts front bar and leave the rear stock

adjustable endlinks (properly set up)

camber kit - van steel sells them

upgraded bushings for the control arms and shock mounts - phoenix, vansteel, lg etc almost all sell some form of bushing upgrade

upgraded shocks (bilstein, kw, or koni sport)

LFZ

DRM Bilsteins and a set of Hotchkis sways and a dailed in alignment....Should be best bang for the buck right there.

ImaRoadDog

Thanks for the replies. I think I will look at shocks and sway bars now that would be compatible with coil overs at a later time. Any specific suggestions? I will also get it a little more aggressive with an alignment (negative camber), plus it would be fairly easy to put it back to street set up in the off season.

08velocity

Lee speaks the truth !! just put hotchkis sway bars on ours and that alone helped huge !!! waiting on my DRM/ Bilsteins for the rest of my " oh hell this thing is even better than ever moment " !!!!

NemesisC5

I used the Pfadt a-arm bushings which were quiet, are there any others available that are quiet as well?

mikeCsix

If you aren't running a camber kit, I highly recommend it. I had an eccentric slip on me one time and I was convinced, plus I was done for the day. if your are driving in the street the camber kit will help preserve your alignment.

From another source, I've also heard the Hotchkiss sways and Bilstein Sports are a really good way to go. I was surprised at Anthony's response, the GS already comes with more than what the old Z-51 setup was. I ordered the DRM version of the Bilstein Sports, awaiting arrival.

If you decide to go with the Hotchkiss setup, I suggest adjustable endlinks from Anthony, I don't personally have experience with them, I have read a lot of good comments as to their performance, being adjustable allows you to set the sway bar up without pre-load, something the OEM links do not do and useful for corner balancing.

ZedO6

Hard to beat the GM T1 sway bar setup with the 3 hole rear bar for an easy and measurable upgrade on the base C6. Of course that assumes you already have a good track alignment.

crimlwC6

All good suggestions but if you are chasing lap times then tires are the answer.

AND0

What's your current alignment?
If you still have stock settings, a track oriented alignment could be worth a couple of seconds on a long track .

SteveC68

Have you done a proper track alignment on the car? If not that is without a doubt the cheapest first upgrade. After that I would get Strano's 33mm hollow adjustable front bar and the DRM revalved Bilstein Sports. Then as mentioned real track tires will be worth a bunch of time.

ImaRoadDog

Have not changed the alignment on the car from the stock settings. I thought the Grand Sport already came with some negative camber dialed in, which is why everyone complains about their tires wearing out so fast on the street. Regarding tires, I would love to run some DOT-Rs but that would bump me up a class (GT-2 to GT-1) and I would rather stay in GT-2. I am currently running the Michelin Pilot Super Sports with a tread wear rating of 300 and am fairly happy with them. Mostly, I just seem to notice a little more lean out of the car and am trying to flatten it out a bit. I took the car in for an oil change the other day and while on the lift I looked at the sway bars, they already look pretty hefty. Don't know the size (mm), but I would hate to replace them with something else only to find out what I had was already pretty good. Appreciate the input from everyone.

AND0

What are your alignments settings ?
The Mich PSS's are the best street tire out there IMHO, but with insufficient camber on the track they will wear out fast.
"I thought it had camber" and "the bars looked hefty " really aren 't sufficient answers to the advice you're getting here.
If you 're serious about track days you need to get the gauges to align it your self , not too hard, or develop a relationship with a local shop you can trust. Alignment is really the first step (with brake maintainance) to track days.

So, what are your alignment settings?

mikeCsix

Knowing the alignment settings is a key step to improving lap times. The stock settings have too much tolerance built in, so if the tech inputs the gm parameters for FE-3 and cranks on the suspension until he gets green numbers, there can be quite a variation in the alignment that will not help you on the track. Also, camber isn't the tire killer that toe is and there is a large tolerance in the gm parameters that will prematurely wear your tires.
To judge a sway bar by looking at its diameter assumes all sway bars are made: from the same dimensional stock. Somehow, I don't think they are. The Pfadt chart is helpful to compare their products with, its unfortunate no other sway bar stats are inluded for comparison.

mikeCsix

The other issue is I think the GS is well balanced for handling in stock form. When you start replacing part just because "they look bigger", bigger isn't always better. You can easily introduce oversteer/understeer conditions trying to get the car to corner a little flatter, at least that is my concern. If you've spent any time looking at the pfadt sway bar chart, you might notice a difference in bias between the various sway bar sets presented. I don't know why that is unless you consider GM for safety reasons, set the car up for understeer and tuned it with the sway bar settings they chose. Where the track oriented cars want a bit of oversteer, hence the differences.

TKOGTO

My 2c = whatever you decide, get a matched set. On an occasional track/street car, you will not likely be tuning the suspension enough to take advantage of mixing products from different manufactures

The Pfadt chart shows some interesting info. In terms of the C6 Z06 and ZR-1, the sway setup actually tends toward oversteer. I thought this odd as virtually all others were set up for understeer or at least neutral. I asked Pfadt why this might be and they replied "The best assumption we have as to why the car oversteers from the factory is for marketing bragging rights. Especially in the last 5-10 years customers have put more and more consideration into Nurburgring times, and GM's marketing department certainly sees the value in those numbers. If you're a gifted driver like Jan Magnussen or Johnny O'Connell it's likely faster to set the car up with some oversteer for the sake of putting down fast laps."

Dan H.