So I'm trying to put 390rwhp to the ground on 20" street tires on a RCSB 2wd with a stock stall. The suspension is completely stock other than 2" shackles and some leaf spring clamps in front of the axle. My current tires are some WORE OUT Bridgestone Dueler H/P 275/55R20's with 20psi in the rears...I have no wheel hop or anything, just plenty of spinning under 40mph! I do have a vibration at 70mph, but I think its more of a tire out of balance. Because its a fairly strong vibration, but it isn't very fast. To even get a decent launch, I have to brake stall to 1500rpm, and keep that throttle position after releasing the brake until the motor slightly bogs, then roll into WOT. Even then I get a bit of wheelspin. And then at 5k rpm, the tires start spinning again, and then truck will spin and sit sideways just a hair on the 1-2 shift! I'm planning on buying some Hankook RH06's in 285/50R20 when cash is available. But I was just curious about pinion angle. Ive never checked it, and really dont know how? How would I check it and what should it be for best traction?

 

Also, I have one piece steel drieshaft if that matters?

 

Oh, and 3.73:1 gears btw

 

your pinion angle is probably pretty good with just shackles. They will point the diff down slightly, and when you get on it, it will come up even with the trans. the reason your spinning so much besides the bald tires, is the stock converter. with my 6 different converters, stock always spun the most.

 

Yea, i know the new tires would cure most of my spinning. But I just want to make sure I'm getting the most out of my setup! Also, correcting pinion angle just might help with my vibrations. Although, bew tires will prolly help that too lol

 

Ig my main question is: how do I correctly measure my pinion angle and what should i set it at on level ground, or a drive-on lift? Ive been reading on the internet for hours and my head is spinning from all the different how-to's I've read!

 

with 2" drop, your pinion angle should be fine..

 

Leave it on level ground at ride height. Make sure the yoke is vertical when you park it so you can put a level on it. Measure driveshaft angle relative to the ground and then pull the driveshaft off the yoke and measure the yoke relative to ground. The combination of the values from both angles will give you pinion angle.

 

What does the time slip look like?

 

Shoot for 3 to 5 degrees negative.