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· wind & fire = guides to power
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Discussion Starter · #1 ·
I'm curious if I can cheaply and easily duplicate the effects of an older Firebird I once had.

It had a custom four link (with panhard bar) and to this day my brother still talks about that car because of the "action".

It was setup so that when it had slicks it stayed level in the rear, but with street tires the rearend would raise up in the air.

I know I can fab something up as far as mount pads for the trailing arms...if I just knew more about geometry of the rearend.

I can also make custom trailing arms so that will not be a problem(and maybe a blessing) if all I have to do is shorten or lengthen the uppers or lowers.



Ok, after reading up on this I am thinking that I can modify the lower trailing arm body mounting point to raise the lower trailing arm.

This should give that "rise" on street tires and a firm bite on slicks...or should i rasie the top mount?

· Registered
2,455 Posts
getting a rise

What will govern the rear end rising under acceleration more than anything is the length of your suspension links.
The shorter, or closer to the rear they are mounted on the frame, the more your rear end is going to "Jack Up", under acceleration. That is due to the point on the chassis where the twisting action of the rear end will have its effect. The closer to the middle of the vehicles front/ rear weight point, you mount the links, the less of a visual effect you will see on chassis reaction in this instance.
In the early 60's, guys were running traction bars that went up as far as the transmission mount. This gave a neat look when launching as it tended to make the front end lift up and the rear end squated. The problem with that was that you had to have super stiff springs on the back to pick up that weight transfer.
During the mid 60's it was found that shorter bars connected behind the center of gravity had more positive effect as they started using the rear axles twisting reaction on take off, to force the rear end downward. This is what makes the rear end want to rise on take off.
IF you are going to relocate the lower links, then you might want to take into consideration the effects it will have on your upper links.
With a 4 link rear and panard bar, you will want your upper and lower bars parallel with each other. Another thing to consider is your pinion angle. Pinion angle can very depending on the type of suspension you are running.
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