Question for track only 4 corner coil over 914s...., what spring rates are you running? Options

[nine14cats]

The Beast is built for coil overs on all 4 corners. What spring rates are you guys with 4 wheel coil overs using?

I know TimT has coilovers if memory serves....

And if you have Fr / Rr weight distribution that would be great.....

My previous track 914-6 had T-bars front / springs rear.

Thanks,

Bill P.

[nine14cats]

Thanks for the info Tim. What I find interesting is how much different the coil overs spring rates are in comparison to T-bars and spring combo's.

On my previous 914-6 the equivalent front to back rates had the softer setup up front, similar to a 911. But I've heard from a couple of people including yourself that they have a heavier rate in the front. I wonder what the physics are behind that? The way T-bars transmit resistance versus a coil spring?

Thanks again!

Bill P.

[byndbad914]

But I've heard from a couple of people including yourself that they have a heavier rate in the front. I wonder what the physics are behind that?
Bill P.

Bill, with my V8 car I had 300 fronts and 450 rears as a "starting point". I can tell you this much - I needed heavier rate fronts for sure. My car was 2305lbs without me in it and 59.5% rear weight distribution. With equal sized 9" wide tires all the way around it oversteered like no other car I have driven!! I maxed the Tarret sway bar in the front to stiffen it up and still had oversteer, but could throttle in understeer slightly.

Ergo the desire for a higher front spring rate for me with that combo. Slivel is correct about different length "advantages" f to r, but rates are dependant on a lot of factors. If you are running the same size tire front and rear, and have a 60% rear weight with an aluminum head 350 Chevy, I would guess a 400-500lb/in front rate with a 450 rear rate would be good to start with. Now I will have 1.5" wider rear tires than fronts, so I may not have to change the front spring rate much to tune out oversteer.

Spring rates will have to be tuned to your combo and what feels good to you, no other way around it and there is so much flex in a tub car anyway.... Some like a car with a little oversteer, others a little understeer. That can be tuned in with spring rates and and adjustable bar(s).

edit - I just realized your "beast" is a six... so somewhat irrelevant on the rears - maybe around 350-400 rears with 350-450 fronts.