Sarge, Pedders question.

[0rion]

In your opinion what are the "must have" pedders pieces and what are nice to have but not really necessary? My bro is interested in doing some suspension upgrades. I took him a mag that I had here that did a pedders install and we were looking over the parts list and were questioning a few of the parts as to whether they were absolutely necessary or just nice to have. Their finished kit price was $2600 and some change.

[Sarge]

What is it he is going to so with it?
I think the absolute/must have are:
Front Radius Rod bushings and Strut Mount Bushings for sure.....
https://secure.merlinsoftware.com.au...IAC&Level2=GTO
https://secure.merlinsoftware.com.au...IAC&Level2=GTO
https://secure.merlinsoftware.com.au...IAC&Level2=GTO

HUGE Difference....

[JusticePete]

The reality of the VZ chassis is it is pretty amazing that it works as well as it does. The engine is placed too far forward and too high for interior space. That makes the GTO nose heavy and drive as though it were a shopping carts with a couple of adults hanging on the front outside of the basket. The front struts are basic oil and air mildly damped units. The radius rod connects well inboard of the knuckle into the control arm. The front radius rod bush is a center loading hydraulically damped design the hyper extends under acceleration and braking. The wheel pivot is well inboard the from wheel and the steering rack connects to the wheel with a tie rod to the knuckle behind the wheel. The Rube Goldberg sway bar endlink double rubber donut contraption is terribly inefficient. To finish it off on the front, the steering rack is slow and spongy and we didn't even mention the strut mounts.

In the rear, they used mini-bloc coils that are light in rate to save interior space at the expense of function. The differential is held in place by four teeny tiny bolts and the differential tail cradled by half finished bits of rubber. There are no rear control arms, just K members and no upper control arms, no trailing arms, no radius arms... The sub-frame attachment to the body are a pair of NVH voided rubber bushes.

As bad as all this sounds, my Pedderised GTO was 2/10 of a second off the time of a 2007 Z06 Vette with track compound tires and an SCCA Steward driving at the GTOAA Autocross. A Pedderised GTO runs exceptionally well.

Orion didn't mention the condition of his GTO so I'll take a stab with a few assumptions based on age and mileage. Most on the road GTOs running OEM suspension would really benefit from what I refer to as a maintenance package.

Up front:

EP9166 Radius Rod Bushes
EP9019 Rear radius Rod Bushes
5851 Strut Mounts
8985L/R Comfort Gas Struts
424209 HD Endlinks

These components used with the OE coils and bearing bring stability to the front suspension. They limit Castor and toe changes that occur with worn and overly compliant OE bushes. The struts are a huge improvement over the basic OE air and oil struts. The endlinks actually allow the front sway bar to work. It is a HUGE upgrade.

In the Rear

7643 OE Height Rear Coils
8081 Comfort Gas Shocks
EP513 Rear Sway Bar Endlink Bushes

These components address the excessive negative camber that comes as the OE rear coils age. They also are higher in rate and probably the rate the car should have shipped with. It will be an excellent balance between the front and rear coil rates. The OE rear shocks are actually decent. They are low pressure nitrogen and oil. The CG Shocks are just a bit higher on the critical damping scale and bring the car to a state more like a BMW or Benz than the Pontiac you purchased. The rear sway bar endlinks are stout and function well. The rubber in them is prone to aging. They become brittle and crack. Replacing just the bushes with urethane resolves the problem.

Fol owing this path you have a GTO with 40K on the speedo that will drive better than it did when brand new.

Now if you are looking for BMW M or AMG like handling we have to gut it and start with a Pedders Track II. Add in our adjustable sways, a Fast Ratio Steering Rack and you will be very close. We do have a closeout on our eXtreme coilovers, 2641 rear coils and GSR 9095 dampers for a ridiculously low price of $849.99 give or take a couple of dollars.

I hope this helps.

[0rion]

yep, thanks to both of you. I'll pass on the info to him. He has on 06 with relatively low mileage and is fairly happy with how the car handles now. Just looking up the road a bit at making it a little better.