Complete G-Body DSE suspension upgrade

[xxxturbo6]

I would like to start this off with a little information on what we’re doing to our GNS Test Car and our goals then move into the build process with some install pictures. Our goal with this car is to frequent Autocross & Road courses while keeping a Track Ready Street Friendly handling car whether it be on the street, at the drag strip or on a closed course. Our motto here is "Function is Everything"!

We chose Detroit Speed & Engineering’s full G-Body suspension package as the suspension for our GNS Test car. We will be at DSE Tomorrow documenting and doing the install. One thing about DSE, They are pounding their cars every weekend, customers are pounding their cars every weekend, and most of the time a DSE equipped car is winning (Frank Serifine) and that alone made it an easy choice for us.




We will start off with some basic measurements to give us a base to start with.

Here are a few basic numbers on our GNS test car:

Wheel base: 2746mm - 108.1in

Track: Front: 1486mm - 58.5in / Rear: 1466mm - 57.7in

Length: 5095mm - 200.6in

Width: 1819mm - 71.6in

Height: 1387mm - 54.6in


Drag Coefficient: 0.410 (Tested by GM)


Current Tire / Wheel sizes: Wheel make- CCW / 3-Piece

FRONT WHEEL: 18" X 9.5" - 4.75 Back Spacing
REAR WHEEL: 18" X 10.0" - 4.75 Back Spacing

FRONT TIRE: 255-35/18
REAR TIRE: 285-40/18

NOTE: No rubbing issues at all with stock suspension!! Went to Hotchkis lowering springs in the rear only and it dropped it perfectly 1". Got minor rubbing so I rolled the lips with the moldings.

A lot more info on wheels & fitment here:18" CCW Wheels on Scot W's car..

Stock ride height from floor to wheel well lip w/CCW wheels:

FRONT: 25.5"
REAR: 27.75"

REAR ride height After installing the Hotchkis lowering springs = 26.75"



4-Corner Scaling: Done on (8/30/10)

Next we SCALED the car on all 4 corners to give us a weight on all 4 corners before installing the DSE suspension. After the installation we will re-scale the car to see how much weight was shaved and where.

When trying to even up cross weight you want to get as close to 50% as possible.

Here is what we had in the car had at Scaling..

* Full tank of gas just topped off!
* Nothing left inside the cars counsel /glove box, no floor mats.
* Nothing in the trunk.
* Tires at recommended pressure.

First we started with leveling the scales on the surface to make sure they were level before we started. This was done using a 6ft level across the scales, and then we jacked the car up in the center and lowered it onto the scales front & rear. With the whole car resting on all four individual scales we took measurements.


FRONT "CAR ONLY" :

* Left = 997 lbs
............................Total front "car only" = 1,953 lbs
* Right= 956 lbs


REAR "CAR ONLY"

* Left = 695 lbs
............................ Total Rear "car only" = 1,436 lbs

* Right = 741 lbs


Completed Percentages & Formula:

Front Bias: 1953 / 3389 = .57627 = 57.6%
Rear Bias: 1436 / 3389 = .42372 = 42.4%


The left front and right rear are heavier than they should be. The left side usually is heavier than the right, - "without driver". Next time we scale the car we will disconnect one end link on the front and rear anti roll bars when scaling, then connect them on the scales and shim them so they don't jack weight from one corner to the other. Doing this removes any unwanted bind the sway bars could be causing. Raising a spring perch on the LF corner will increase weight on the LF and RR corners.

Our left and right side weights add up to almost even, so by adjusting the heavy corners we should be able to balance them pretty close without driver.


Next post will be install pictures and more measurements.


SW.



Picture below is how the car sits now... Stay Tuned! More to Come!!!