Tim,

I have a 1984 Monte Carlo with a 9-inch Ford rear end. I have installed adjustable upper control arms and aftermarket lower arms. I am looking for a good number to start with on setting the pinion angle and also the best way of measuring this. The engine¹s dyno horsepower is 727. I am going to use 250 hp of nitrous after the car is sorted out. The rearend ratio is 4:10 and I am using a turbo 400. I have not had the chance to weigh the car yet.

Thanks.
Rick

Rick,

I am going to assume that you purchased the control arms with the solid rod ends. Pinion angle is going to be measured as the difference between the centerline of the driveshaft and the centerline of the pinion shaft. The best tool to use is a digital protractor, since the small dial types are very hard to read at fractions of degrees.

ADVERTISEMENT

With the rearend of the car at ride height, place the protractor on the driveshaft and record the degrees. Do the same on the pinion yoke, making sure the yoke surface is square to the pinion centerline.

You will want a negative pinion angle in this car. This means that if you look at it from the side, it should look like a V. Try to get a 2- to 2.5-degree reading. If you have neoprene bushings in the links, try to get around 5 degrees negative.

These readings will be very close to keeping the driveline straight during acceleration.

Good luck.

Tim

< MORE STORIES >