GKennedy

Hi, Guys
I have a C5 Z06 all gutted dedicated for HPDE only, with stock suspension so far.
Looking know for the best bank for the bunk in suspension upgrade.

Coilover or Liftspring
The comment that I read here seam to give advantage to the coilover setup.
I'am wondering also if the coilover would shave some weight compare to the liftsprings ? ( I would like that ).

Looking to spend 2k or 3k for the setup ( inclued sway bars )

I would like to hear your suggestions.

Supercharged111

The Pfadts are marginally lighter and, IIRC, the LG units are slightly heavier.

rfn026

Shocks are a tuning device. They're the last thing you want to change. You've complicated the question though by considering coilovers. You're going to need a serious testing program for this. First you have to get the springs and sway bars correct. Once you have those things under control you can play with the shocks.

Keep in mind that this is an HPDE car. It's not a race car. You're going to spend a lot of money and you could make the car worse.

I just added an article that I wrote a few months back regarding performance shocks.

Are you taking tire temps?

Richard Newton
Car Tech Stuff

JerryTX

LG G2 coilovers (non adjustable) and Mono Ball control arm kit. Makes the car extremely predictable and it is DIALED IN! Show up and drive and all the adjustment time can be spent tuning the ***** between the ears. I started racing with a new-to-me track car and had far too much to mess with and get reliable. Lou and Anthony set me up and it has been great working on consistency and race craft versus a hundred other concerns with the suspension. The car is now a consistent front runner in ST2 and, while undergunned in ST1, still does well, and I have a lot yet to learn.

0Johnny@MTI

http://www.mtiracing.com/mti-bilstei...coilovers.html

on our test mule our the MTI Coils made the biggest improvement as far as lap times and driver feedback.

Tire temps relate to spring rate- not shock tuning... unless your getting massive wheel spin at corner exit because bc your front rebound is too stiff.

drivinhard

best and bang for the buck aren't going to be the same, but for bang for the buck, it's hard to argue with the old tried and true TTA/PTA set-up a lot of C5Z's ran for years and years.

Pfadt Poly bushings
T1 bars
powergrid end links (quiet, strong, easiest to adjust)
Delrin shock bushings
04Z shocks
lock all your camber in place

fits in/under your budget, and it works.

brkntrxn

To give the OP and idea on track times, the setup Mark outlines is good for low 1:3x's at Road Atlanta, low 2:0x's at VIR, low 1:40.0x's at CMP, and low 1:18s at Charlotte. Roebling is around a 1:17 as well.

96CollectorSport

I would suggest changing out the stock rubber bushings before you do anything else, weather you do the Delrin from Phoenix or Van Steel or bearings from LG, DRM or Pfadt. The bushings would be the first thing that needs to be changed. It would be like doing a head and cam but leaving a dirty stock paper air filter in and leaving on the stock exhaust manifolds. You would be limiting the performance benefit of the head and cam components because you didn't take care of more obvious things first.

To get faster lap times you have to feel confident in the handling of the car, if the car is predictable you will be more confident in the car. Removing the compliance out of the suspension will help the car feel more predictable. If you install bushings and have the car set-up I think you would be surprised by the difference.

mountainbiker2

You didn't mention what tires you're running. If it's not Hoosiers A6's, then I would start there first.

Steve A.

drivinhard

cruzin2

Tires and bushings are the biggest move for your money.

0Anthony @ LGMotorsports

Not sure where you have your data from on that one but the LG G2 coil overs are 16.1 lbs lighter than the factory shocks/springs/brackets all things considered....and less un-sprung weight to boot.

0Anthony @ LGMotorsports

There are a number of things you can do....I'm assuming a few things here:

• Already has a good track tire
• Already has a good seat
• Already has good wheel bearings

Given the above is true....I would start with the basic's. Get the bushings upgraded first and install a camber/caster kit so you know for sure that the wheels and tires stay pointed in the right direction and the alignment is how it should be. There is a lot to be said about a good setup on a car too. Doesn't matter if you have the best of the best on it, if the tires are not pointed in the right direction it doesn't matter.

Once that is done, I would say sway bars would be the next best bang for the buck.

After that...then we can look into a spring, shock, or coil over upgrade depending on what you are planning for the car.

More than happy to talk about any of the above, just hit me up here any time.

GKennedy

Thanks to every body for sharing all that informations.

crimlwC6

My 2 cents are that LG's advice is better than mine and I think it's impressive that he isn't trying to take all your $$$ by up selling you. I don't MTI is trying to upsell you, I've been to their shop and it is impressive!
I've got a gutted C5 FRC that weighs just about 2800 with no driver. I've got stock leaf springs, used pfadt inverted single adjustables, O'Connell sway bars, used pfadt monoball control bushings, and a pfadt camber lock kit. I'm a cheap bastard!
The camber lock kit and sway bars are your first step imo. As LG said if you can't keep your alignment , then the rest is rather futile.
I ran those bars, shocks and camber lock on my ls3 c6 before swapping them over to the C5. I don't know how much to attribute less weight vs monoballs for the turn in my car now has, but it is fantastic. You can have a great handling car without coilovers and if you don't know what you are doing or don't have the time to adjust the car (weekend warrior vs. practice time with a suspension engineer then adjustability can be a liability. I adjusted my shocks for the first time in a half a year (roughly 10 track weekends) last week and went right back to how I had it. My car does ride very high; I can stick four fingers vertically between the tire and the fenders but it also works very well. Last point is to be brutally honest with yourself, how good are you? If you aren't in the top 5% of drivers at the track you probably can't extract the benefit of coilovers. However if you get a consistent, well balance car and get a few years of track time you might get there and then decide to do coilovers.
Here is a video of my car running with Nt01s vs C6s with 200 more hp, coilovers and slicks (dunlops and michillens iirc). My car is probably 300 lbs lighter. I run a square setup with 315 NT01s on heavy *** C4 ZR1 rear wheels. Skip to about 4 or 5 minutes into the video. At around 10:20 I had to back off because of oil temps (oil cooler goes in this winter).

jsbwac

LG coilovers. Best mod I made to suspension and car handles like it is on rails.

jcsperson

Very informative, but your camera needs to be about 3" higher. I felt like I was in the back of a dump truck while watching that.

ZedO6

Refreshing to find a CF vendor that isn't trying to "load the boat" with every suspension product in the catalog and is actually giving cost effective and sound advice in the best interests of the OP!

Reaffirms another solid reason to vote with your dollars at LG.

crimlwC6

I'm short so I want you to feel the same! I've moved the camera up

mr.beachcomber

All the recommendations so far are excellent; however, not to be a wise guy, but I think that the best bang for the buck would be a High Performance Driving School like Skip Barber's. Even though you're only doing HPDE's, you can over drive your vehicle to the point that consistency in lap times and suspension feedback are nil.

Forty years ago I thought that I was a red-hot driver (after all, I drove a Corvette race car) until I went to Skip Barber's school to fulfill the requirements for my SCCA club racing license. The weekend course taught me more than just the basics of racing. It proved to me that over driving the Vette was not the fastest way around the track. Before I stopped instructing, the most common student error I encountered was over driving their vehicle during HPDE events shredding tires, overheating the brakes, and sometime breaking suspension parts during an "off" (with those that refuse to listen to their instructor).

Have fun with your HPDE C5 Z06!