Tim,

I have a '72 corvette that was back halfed a few years ago. It has a 4-link with a ford 9 in. rear. The original frame was cut right before the rear fender wells. The 4 link rods are a bit short at 21 in. Does this matter? I want to step up to a faster class. (9 sec. range). What type of frame configuration do you recommend for a fast bracket car like

this? Can I use a chrome molly cage with a mild steel tube frame? Can they be mixed? It's a bit tight to get in and out with a regular cage.

Thanks. (You are the greatest!)

Charlie

Charlie,

The four-link bar length you have should be fine for your car. It is acceptable to use a chrome moly cage on the mild steel frame. I would use a good pair of double adjustable shocks along with the four-link you already have and an intersect points of 55 inches out and 4.5 inches high.

Tim

QUESTION 2

Tim,

I have an '82 Mustang with a ladder bar coilover setup. It has always gone straight until I put more power to it. Now it does a wheelstand, but pulls to the right. I'm putting wheelie bars in it, but it still goes to the right. What do you think the problem is and how do I fix it?

Bobby Peaden

Bobby,

The first step would be to check if the rear suspension is straight and square in the chassis. Next, put the car on scales and look at your rear left and right weight percentages. You are probably going to see more weight on the left rear tire.

If your ladder bars have an adjustable link, you can move some of that weight to the right side of the car, just like adjusting the pre-load in a four-link car. The wheelie bars you just installed can be a valuable tuning tool. Lowering the left side wheel will take some of the load off of that tire and steer the car back to the left.

Tim

It's been a while since we had a chassis Q&A, but we now have veteran chassis builder and Pro Mod racer Tim McAmis to give you the benefit of his years of experience. So keep those questions coming to chassis@racingnetsource.com and look for the answers right here in Check Out This Chassis!

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