Been mentally, (no jokes now), building a dedicated drag car, and giving thought to the suspension, or possibly lack of.

Thinking along the lines of top fuel or funny car, and knowing that there's really no suspension to speak of, am wondering how the same principle might apply to a steel full-body car.

Giving thought to solid mounts at the engine and trans, also carrying the practice through to the rear diff, but leaving front suspension alone. I would think that a solidly mounted rear axle would do away with the natural concept of "wasted" energy through unnecessary motion.

Admittedly, this may be harder on axles, being as all torque is being applied through the rear, without any suspension to take up shock loads.

Started wondering if some of "our" fast car guys might have any input along these lines.

Roger

Roger, with a solid axle, would you eliminate wheel hop by run very low air pressure?

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Cheers!
Al T

You would think it would rattle out your fillings.

Well Al, the top fuelers have the same problem of wheel hop, and the only "suspension" they have is low pressure in the drag slicks. I will admit that the possibility is real, and does bother me a bit.

Autotrans, you too, have a valid point. I ask that you notice I did say dedicated drag car. It won't be driven on the street, only down the 1320 and around in the pits, and on drag slicks at that.

The reason I ask is that I have the chance at a possible roller that's in a salvage yard. The title has been officially junked, though, and in Iowa, there is NO WAY that I can retitle it for street use. (Although my ideas would make a surprising street car).

Roger

On my "street strip" Drag car I have polygraphite (plastic) front spring eye bushings and a super stiff (8 leaf) front spring section. The back of the leaf spring is real soft (5 leafs with no clamps) so it does all the flexing work while the front segment keeps the rearend located.
Add a pinion snubber and you good into the 10's
DD

I stand corrected. Fillings don't matter when you're sailing down the quarter.

Drag cars tend to have pretty light springs / suspension to help weight transfer...
It's the high RPM engine and hard shifting trans that will knock fillings loose

Funny cars get away with solid suspensions because they have around 7000 horsepower and a slider clutch.

Fuel cars have 7000 horsepower, a slider, and a 300" chassis that acts as the suspension. (Watch them bow up in the middle)

Pro Stockers have limited suspension travel because they have 1400 horsepower, sliders, and 5 gears.

A low horsepower car with solid suspension will do really good burn-outs off the starting line.

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Official Cookie and Mater Tormentor.

I'm with Dennis and Doc here. If you make it solid, there will be nothing to absorb the shock of launch (unless you have 4 ft tall slicks with 4psi air or something), and the impulse from the drivetrain will just make you sit and spin.

Lou

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Home of Slant6-powered fun machines since 1988

Ok, guys...you convinced me. I hadn't really thought it through to the point of what happens at the contact patch with all the torque getting to it. I was kinda figuring that a slant and auto trans might not overload the friction of a slick, but realized how wrong I was when I remembered some of the burnouts that my old '68 has done at the local strip.

So I'm interpretting your advice like this; Poly spring bushings front and rear eyes and build a custom spring from a stock leaf pack, plus three or four 1/2 leaves in the forward half of the spring assy. Good clamps on the front half and no, or loosely applied bolt-on clamps on the rear half.

I just love brain-storming sessions.

Roger

I think you got it...
That's what I have going under my drag car.
Try to pick the flattest / softest springs you can find or de-arch some. Shoot to have the spring pile near flat, that helps keep the rear shackles leaning reaward and promotes body rise as the axle housing wraps-up.
Use soft shocks and don't forget the pinion snubber.
DD