[ry57pont]

So after loosing my wife in 2017 im trying to get back into racing, i bought some 4:11's and have a question relating to driveshaft angle. its a 4 spd car, 500 flywheel hp, according to my drawing do i have 2.35 degrees total? is this enough?

[73 TRANSAM]

trans output and rear yoke is in the drawing with no drive shaft right? If no DS then yes you have 2.35 angle. But I belevee you need more unless if your running a 4 link. If leaf spring car, you would like 4 or 3 angle down to compensate for the rear end climbing up under hard acceleration. Sorry for your loss!

[ry57pont]

Trans output and slip yoke is not pictured. just the driveshaft and rear yoke on the 3rd member. it is a 4 link with H&R anti roll bar. everything BMR and completely adjustable. it seems like it has the ability to hook hard at this pinion angle but i never thought it was very much angle.

[ry57pont]

i have read that 3 to 5 negative (down) is ideal, but according to Dick Miller's book he looks for 1 degree down for every 100HP. so i dont know what to think

[Old Man Taylor]

I run 4 degrees on both of my cars.

[AG]

You need to measure the angle of the trans yoke and pinion yoke, noting the direction (up or down), then subtract them to get the pinion angle. What you want depends on rear suspension for example, Caltracs about negative 3 degrees, four link, negative 1-2 degrees. It's all about how much twist you get on the rear pinion.

[ry57pont]

thanks all, i set it to 3.5 and will adjust from there. stay warm everyone. - RB

[adam woodmancy]

fwiw, my factory 4 - link is set at -2 with rod ends and solid bushings. i would belive that poly or rubber bushings would be closer to - 4 or 5. its definately not a powerhouse, 405 cid, made 523 and just under 500 ft lbs on the engine dyno, but it has been 1.58 60 ft using the transbrake and 1.56 foot braking. i think the slower 60 ft using the transbrake is due to flex in the upper bar mount on the frame. i plan to reinforce that before the car goes back out. mph performance is almost identical, my car is probably 100-115 lbs lighter. Be sure to let us know how it is working for you. good luck to you! -adam

[428goat]

Just put the Tremic drive shaft angle finder app on your phone. It’s free. Works great. It uses your phone to find angles. Best if used on a ramp style lift so all four wheels are on it. I used it on a two post lift bu jacking up the rear end .