playing hookie

if you were building a leaf spring street strip #3900 truck what would you build. gearing, tires, posi, traction bars, shocks

3900 lbs is a bunch of weight to move for a decent et, not to mention its a truck so it likely will be as aerodynamic as a refrigerator.


Assuming your build is a typical street/strip build BBF and you're looking for a leaf spring combo I'd probably go with Caltracs. I'd consult Calvert Racing as to shocks and spring rates to use with them on your combo.

I have no faith in a posi's clutches holding up given the weight, typical BBF torque, and a truly sticky tire. I'd lean towards a detroit locker in a 9". A little clunky on the street but strong and much better two wheeled traction under power. I'd probably gear it a little deeper than I would a lighter vehicle but it all comes down to "what rpm do you want to be at in the traps?" given your tire size, etc.

For tires it would depend on how much street vs track time. If I was all about making it as quick as possible I'd go with an old school ET Street or similar. Bias ply... slick with a few DOT friendly grooves in it. If I was looking to drive it more on the street, I'd go with a drag radial. But it's an art getting your vehicle set up to hook with them when the wick is turned up.

this is where im at its 1952 f1 the engine is 470hp it runss 11.60s with a best of 11.38 @ 117. would like to get a little more out of it. here's the combo 470hp 472, 4000 stal,l 700r4 overdrive, 3.89 true trac posi, 275x60x15 mt dr. the 60' are in the 1.60's with a best of 1.51 my thinking is that stepping up the tire to a 30" over the 28" would help what your thought.

Ok. I was unaware of the combo previously. I never had any luck getting a 700r4 to hold up to low 11 second passes. Several "bullet proof" builds from respectable tranny guys and I'd turn 3rd gear into another neutral on the hose behind a sbc. Good for you. With the deep first gear it's likely helping get that heavy ride up and rolling. Mid to low 1.6's in the 60' is what I'd expect given your ET/mph. And getting the DR's to hook like that in a pickup means you're definately doing somthing right. Congrats!

Going up to a taller rear tire increases contact patch but decreases the combo's gearing. The truck may hook harder, but its also possible it will fall out of its power band on that steep 1-2 shift on the 700's and your rpm may not be optimal at the traps. I guess If I was to try the 30" tires I'd also consider a 4.10 in attempt to keep the overall gearing the same because what you have is mainly working.

What's in the '52 for rear suspension now?

4thHorseman wrote:Ok. I was unaware of the combo previously. I never had any luck getting a 700r4 to hold up to low 11 second passes. Several "bullet proof" builds from respectable tranny guys and I'd turn 3rd gear into another neutral on the hose behind a sbc. Good for you. With the deep first gear it's likely helping get that heavy ride up and rolling. Mid to low 1.6's in the 60' is what I'd expect given your ET/mph. And getting the DR's to hook like that in a pickup means you're definately doing somthing right. Congrats!

Going up to a taller rear tire increases contact patch but decreases the combo's gearing. The truck may hook harder, but its also possible it will fall out of its power band on that steep 1-2 shift on the 700's and your rpm may not be optimal at the traps. I guess If I was to try the 30" tires I'd also consider a 4.10 in attempt to keep the overall gearing the same because what you have is mainly working.

What's in the '52 for rear suspension now?

i have s10 leaf's with home made cal trac's. your right about the 700r4 but if built right they will hold mind is my own build using a probuilt kit and does hold up up to a small hit of nitrous 125hp taking me into the 10.90's