Spring rates

[captdigi]

I know this is a loaded question… However, I just bought a PFM last week and put it on a stand today to fix the left side pod floor (small crack). When I looked inder the car, the wood under the engine was worn away, as was the first 5 inches of the diffuser.
My question is what is an average spring rate for the rear of the car?? And typical ride height (measured where?) for a driver that is say 190 lbs???? It appears that this car has been dragging the rear around under load.

[LarryWinkelman]

I know this is a loaded question… However, I just bought a PFM last week and put it on a stand today to fix the left side pod floor (small crack). When I looked inder the car, the wood under the engine was worn away, as was the first 5 inches of the diffuser.
My question is what is an average spring rate for the rear of the car?? And typical ride height (measured where?) for a driver that is say 190 lbs???? It appears that this car has been dragging the rear around under load.

I would recommend reaching out directly to someone running the cars, but failing that - there appears to be a wealth of information here:
https://starracecars.com/resources/

The 2009/10 Suspension update document has a sample baseline setup, as well as a bunch of technical information. There's also information about just about every system on the car.

[captdigi]

Yes. I’m hoping that someone who is my size, that is actively racing, would respond with info. However, the link you provided will answer many upcoming questions. Thanks.


=LarryWinkelman;652568]I would recommend reaching out directly to someone running the cars, but failing that - there appears to be a wealth of information here:
https://starracecars.com/resources/

The 2009/10 Suspension update document has a sample baseline setup, as well as a bunch of technical information. There's also information about just about every system on the car.[/QUOTE]

[CSasfai]

I'm a little lighter than you (about 25 pounds), but I also often run the car full of fuel just so I can get multiple sessions between fuelings (which means I'm carrying an extra 40 to 45 pounds that I don't really need in the beginning). At VIR or Road Atlanta, I run 900 pounds on the front and 800 on the back with about a 1.5 inch ride height. For me, that's a comfortable setup and the car never bottoms out (my Formula Mazda, on the other hand, will bottom out consistently at a couple spots at VIR). You didn't specifically ask, but I also run a little toe in on the front - simply driver preference (tight versus loose setup).

[captdigi]

Thanks for the response!!
What ride heights are you running, and where are you measuring?
Thanks Much!!
John


QUOTE=CSasfai;652579]I'm a little lighter than you (about 25 pounds), but I also often run the car full of fuel just so I can get multiple sessions between fuelings (which means I'm carrying an extra 40 to 45 pounds that I don't really need in the beginning). At VIR or Road Atlanta, I run 900 pounds on the front and 800 on the back with about a 1.5 inch ride height. For me, that's a comfortable setup and the car never bottoms out (my Formula Mazda, on the other hand, will bottom out consistently at a couple spots at VIR). You didn't specifically ask, but I also run a little toe in on the front - simply driver preference (tight versus loose setup).[/QUOTE]

[Fred Michael]

It will depend on what tires you are using and what generation of rockers are on the car

[CSasfai]

I measure the ride height at the front of the shovel and back edge of the belly pan. I think I have about a quarter to half inch of rake, I can't remember exactly. I know the front is 1.5 inches.