BIG 928

ive recently swapped from racing a 928 gts to a 993 gt2 here in the uk, in the porsche open series.
does anybody know what spring rates factory cars or privateer cars raced with?And also roll bar thickness front and rear.
i am wondering just out of interest, any ideas would be helpful

thanks mark

bb993tt

You might want to PM "porschemeister". He campaigned one of these back in the 90's. Also just built himself a street legal version with a lot of original parts.

Spartan

We cannot answer any of your questions until you post of pics of your GT2

Jean

You might have your answer here. This is very subjective depending on track, engine, aerodynamic downforce setup, tires, driver etc... but this is a base.

https://rennlist.com/forums/4177517-post6.html

Jean

Sorry Spartan, pictures first! how do I delete my post???

Rassel

Exactamundo
No Pictures = No Answers.

Geoffrey

Some of the GT2s came with "Versa" springs which allow you to change the spring rate by rotating them between 4 settings. They were available in:

Blue series 235, 252, 269, 286 Nm/mm
Yellow series 270, 287, 305, 320 Nm/mm
White option 284, 298, 314, 333 Nm/mm
Red option 296, 312, 330, 350 Nm/mm

Other configurations were
Front 260 Nm/mm
Rear 280 Nm/mm

Front option 280 Nm/mm
Rear option 300 Nm/mm

Spring rates will vary depending on driver, car weight, track condition and general preference.

Jean

Geoffrey has been more thorough, my above post is based on Yellow front and Red rear option combos per factory reco, according to the four spring rates highlighted in his post for each of those colours..

Front Yellow: Rear Red
Option 1(lbs/in): Fr. 1543 Rr. 1693 (270NM/mm; 296NM/mm)
Option 2(lbs/in): Fr. 1640 Rr. 1783 (287 NM/mm; 312 NM/mm)
Option 3(lbs/in): Fr. 1743 Rr. 1886 (305 NM/mm; 330 NM/mm)
Etc..

BIG 928

thanks for your answers so far. i dont know how to post pics, if anyone can post it that would be great.

its on www.newworldmotorsport.co.uk. if you click on gallery then go to the bottom of the page on porsche club motor sport 2009. then go on porsche open anglesey 19-4 09 its the gold car number 17.

thanks again mark

Rassel

You mean this puppy?




That's quite a body kit there!

Geoffrey

Bear in mind that that car is far from an original GT2 configuration so the base springs probably are not applicable. I'm not sure what you are really after in terms of springs, but a lot will depend on your driving skill and a softer setup, while possibly not the fastest setup, might be the best to start with and build skills. A very stiff car requires a lot of skill because the weight transfers much faster and you need to be "ahead of the car".

N-Dub

Bear in mind that that car is AWESOME!!!

BIG 928

thanks those spring rates are a lot stiffer than i use currently.
it is a tube frame car but has 993 gt2 suspension throughout,the engine is gt2 with evo pistons old style valve lifters {not hydraulic}cams etc k26's and multi throttle intake. the plenums are quite high thats why it has those ugly ducts on the rear wings to get air to the intercooler which is now where the rear window should be.
i was just wondering out of interest about the springs ,thanks mark

Rassel

Mark,
You don't have any pictures perhaps of the car without the panels?
Would be interesting to see the build.

Geoffrey

Stiffer is not always better and driver skill has something to do with spring rates too. Since your car is a tube frame car I'd hope that when they built it they relocated the front and rear suspension pick up points. This will help with the toe change that occurs in the car under compression and rebound. There is a lot to be gained by setup and adjusting the kinematic toe so there is minimal "bump steer".