irex511

Hi Folks,

Now that I've introduced myself in the main forum, I wanted to get into some of the main setup questions that I have after purchasing the car.

Sincere apologies, since I'm sure most of this has been posted on other parts of the forums. I've been searching around over the past couple of weeks and just wanted to get a couple of simple questions answered as I prepare for track season.

First, the background:

Previous Car: e46 M3 - D/A Coils, Brakes, SSK, Harnesses, etc.
Racing Exprience: 8 years Autocross, 1-2 years HPDE (limited based on time).
Primary Track Use: Summit Point, VIR, Autocrosses (Washington DC Region)

The new car:
2009 Lingenfelter Z06 - Important Mods

• LPE 630 HP Kit
• PFADT Original S/A Coilovers
• PFADT Sways
• Brembo GT BBK w/ Brembo Pads

Questions:

1. Proper Ride Height for Correct Suspension Geometry? The car is low (doesn't pass the boot or speedbump test), and though this looks great, I'm curious if this is the best height settings for the car. Is there a standard? For the M3 it was 13f,13.5r Hub to Fender.
2. Suggested starting suspension settings? My plan was to start very soft in the rears and someplace in the middle up front. I know most of this is for feel, but I also get the feeling the car will be very power-on-oversteer heavy. :-)
3. What wheel/tire size is most common? 18"ers in the rear would certainly help with tire cost.

mbeckers

For wheels I run 18 x11 in front and 18x13 in the rear with my Z06. For tires I like to run Michelin S9H slicks, 27/65 18 in front and 31/71 18 in the rear. There are more track tire options with 18 inch wheels on all 4 corners. I have kept my ride height stock so I can't speak to the optimum height with a Pfadt set-up. I believe Pfadt has some technical data on their website for alignment and ride height.

Pfadt Racing

Well there really isn't a specific ride height that works perfectly for all Corvettes. The way the suspension is designed there is actually a pretty big range of adjustment where the car works really effectively. For mostly street use with some occasional track days, setup the car where it visually appeals to you but still allows the car to be easily driven without scraping too often... then get it corner balanced and aligned for best performance.

If the car is going to be a track only vehicle generally a little lower than street car height is going to perform better, although there comes a point where you can be too low. You will know you're too low if you begin to have issues getting the car on and off the trailer or rubbing body work while coming off of curbing on track.

If you're a full on race car including Aero running the car as low as you can without clearance issues is going to work best. This may require increases in spring rate.

Our recommended general use ride heights are:
C5 - Front, 26.7" Ground to top of fender. Rear, 27.6" Ground to top of fender.

C6 - Front, 26.4" Ground to top of fender. Rear, 27.3" Ground to top of fender.

Let me know if you have any questions!

Vettechris996

Pfadt, are those ride heights recommended just for coil overs or is that what you recommend to car still running leaf springs as well?

jd86L98

I am interested in this as well?

z060ntrack

No offense to Pfadt (I have their bars) but measuring fender height, when they aren't equal to begin with, could be a recipe for a disaster. If you try to set ride height that way you'll be corner weighting the car without scales

The appropriate rake is 70 mm front to rear as measured at the ball joints. The height can be whatever, but rake is critical in a Corvette

Pfadt Racing

These ride heights are recommendations for coilover cars only. We do not recommend running aggressively low ride heights on leaf spring equipped Corvettes due to limitations in suspension travel, and the adverse effects to handling and ride quality that can result from running the car off the bump stops.

Our general recommendation for lowering Corvettes on bolts is that a little is good, but a lot can be bad. With a well designed coilover you don't really have to worry about running out of shock travel so it opens the door to running the car a little lower.

Vettechris996

Thanks for the clarification Pfadt.

Point taken about measuring fender heights, as long as you use those number as a guide and check rake properly, THEN put the car on scales and corner weight you should be fine though.

irex511

PFADT, thanks for the comment here - this is exactly what I was looking for. I will definitely corner balance the car, but just wanted some general guidelines as a staring place.

It's great to see you guys with a presence here on the forums.

Cheers,

Mike

jd86L98

Thank you for clarifying that.