Lola T540 F/F, autocross duty, spring rates

[r33rob]

I'm restoring a Lola T540 F/F that will likely see autocross duty when finished. I'm looking for ideas on spring rates for autocross. The car appears to have the original suspension.

Thanks, all.

Rob S.
Nederland, TX

[CM/FFdriver]

I'm restoring a Lola T540 F/F that will likely see autocross duty when finished. I'm looking for ideas on spring rates for autocross. The car appears to have the original suspension.

Thanks, all.

Rob S.
Nederland, TX

Hey Rob,

I'm not sure what your running spring wise but from the time I got my car I've only raised my spring rates by 100lbs from the spring the car came with. So I think that's a good base line to work off of.

Ben

[S Lathrop]

The most important variable in setting up you car is getting the spring rates right for you application. In tuning a car, getting the spring rates optimized is step 1. And as you change spring rates, you have to change ride height to compensate for a spring rate change.

For every spring rate you choose, there is an optimum ride height. For optimum performance you want the ride height as low as possible for a given set of springs.

As a starting point, you need to know 2 details about your car: the motion ratio of the shocks movement to the wheel movement and the load on each wheel. Likely your car has a motion ratio some where around 0.5. The motion ratio squared times the spring rate gives you the spring rate at the wheel. 0.5 squared is 0.25 and that times 500 gives you 125 pounds per inch at the wheel. This means that you need to compress the suspension something like 2 inches to support the car.

For a Zink Z10, 1000 pound springs are not uncommon at all. We have run springs even stiffer. The motion ratio is similar to what you have.

[CM/FFdriver]

For a Zink Z10, 1000 pound springs are not uncommon at all. We have run springs even stiffer. The motion ratio is similar to what you have.

WOW! really? so are you saying 500lbs each side or 1000lbs each side? I see you point but wouldn't you want the car suspension to work a little?

Ben

[S Lathrop]

WOW! really? so are you saying 500lbs each side or 1000lbs each side? I see you point but wouldn't you want the car suspension to work a little?

Ben

That is a 1000 spring on each side. That gives you a wheel rate about 250 pounds per inch.

You will need to bump the rear springs so the wheel rate is some what similar to what you have at the front. A rear spring of 1200 lbs/in should give a good balance.

Also you can expect to lower the car My guess is that you will lower the front 1 inch and the rear 1/2 inch. That was based on a starting front ride height of 2 inches and rear 2.75.

[CM/FFdriver]

That is a 1000 spring on each side. That gives you a wheel rate about 250 pounds per inch.

You will need to bump the rear springs so the wheel rate is some what similar to what you have at the front. A rear spring of 1200 lbs/in should give a good balance.

Also you can expect to lower the car My guess is that you will lower the front 1 inch and the rear 1/2 inch. That was based on a starting front ride height of 2 inches and rear 2.75.

WOW, outboard suspension is a whole new ball game, also is this setup for road racing?

Ben

[S Lathrop]

WOW, outboard suspension is a whole new ball game, also is this setup for road racing?

Ben

This is the same for inboard suspension as well. The same physics apply.