jeffery
New Member
Hey guys,
I found this information and i wanted to pass it on.
Vince
Pinion Angle
We'll now open one of our favorite cans of worms, as whichever expert you consult will give you a different answer, depending on their particular automotive area of expertise. The pinion angle is the angle of the flange on the front of the rearend (the pinion) in relation to the angle of the driveshaft. That everyone will agree on. Well, most everyone anyway. It's how you measure that angle that causes disagreement.
But first you should understand why pinion angle is important. As power is applied, and the drivetrain is under load, the rearend tries to rotate around itself, meaning the pinion will rise. The goal is to create a straight line from the back of the crankshaft through the transmission, driveshaft, and the pinion of the differential, under load, so to achieve this under power, the pinion has to be angled slightly downward from the driveshaft when the vehicle is at rest. The awkward part is determining that angle. Different suspension setups will require different angles, though parallel leaf springs will require the most, owing to their tendency to "wind up." While all this may seem overly scientific, and the stuff of drag race chassis tuners, it is important on street cars, to eliminate driveline vibrations or ultimately component failure, and to ensure the longevity of your universal joints and bearings.
So what's the ultimate angle then? How long is a piece of string? Classic Performance Parts suggests mounting the engine and trans at a 4-degree-rearward angle, so the carburetor flange is parallel with the ground, then setting the pinion at 2-3 degrees upward from the ground, so that under load it will move upward, aligning it with the driveshaft and making the pinion angle 1-2 degrees. Currie Enterprises, who has manufactured more rearends than anyone else for the hot rod market, suggests a 1-3 degree angle between the transmission tailshaft and the driveshaft, and an equal angle between the driveshaft and the pinion. The centerline of the tailshaft and the centerline of the pinion shaft will be parallel, the angles mentioned above allowing the driveshaft to run between the two components using universal joints, which have a safe operating range of between 1 and 3 degrees. Obviously, zero degrees is the optimum, but U-joints work at their best when running through a slight angle, hence the 1-3 degree measurement.
If this is confusing, take a look at Inland Empire Driveline's Web site (Inland Empire Driveline Service, Inc. - Driveshafts, Pinion and Transmission Yokes, Center Support Bearings) under powertrain setup guides, where an excellent explanation with diagrams will clear up everything.
I found this information and i wanted to pass it on.
Vince
Pinion Angle
We'll now open one of our favorite cans of worms, as whichever expert you consult will give you a different answer, depending on their particular automotive area of expertise. The pinion angle is the angle of the flange on the front of the rearend (the pinion) in relation to the angle of the driveshaft. That everyone will agree on. Well, most everyone anyway. It's how you measure that angle that causes disagreement.
But first you should understand why pinion angle is important. As power is applied, and the drivetrain is under load, the rearend tries to rotate around itself, meaning the pinion will rise. The goal is to create a straight line from the back of the crankshaft through the transmission, driveshaft, and the pinion of the differential, under load, so to achieve this under power, the pinion has to be angled slightly downward from the driveshaft when the vehicle is at rest. The awkward part is determining that angle. Different suspension setups will require different angles, though parallel leaf springs will require the most, owing to their tendency to "wind up." While all this may seem overly scientific, and the stuff of drag race chassis tuners, it is important on street cars, to eliminate driveline vibrations or ultimately component failure, and to ensure the longevity of your universal joints and bearings.
So what's the ultimate angle then? How long is a piece of string? Classic Performance Parts suggests mounting the engine and trans at a 4-degree-rearward angle, so the carburetor flange is parallel with the ground, then setting the pinion at 2-3 degrees upward from the ground, so that under load it will move upward, aligning it with the driveshaft and making the pinion angle 1-2 degrees. Currie Enterprises, who has manufactured more rearends than anyone else for the hot rod market, suggests a 1-3 degree angle between the transmission tailshaft and the driveshaft, and an equal angle between the driveshaft and the pinion. The centerline of the tailshaft and the centerline of the pinion shaft will be parallel, the angles mentioned above allowing the driveshaft to run between the two components using universal joints, which have a safe operating range of between 1 and 3 degrees. Obviously, zero degrees is the optimum, but U-joints work at their best when running through a slight angle, hence the 1-3 degree measurement.
If this is confusing, take a look at Inland Empire Driveline's Web site (Inland Empire Driveline Service, Inc. - Driveshafts, Pinion and Transmission Yokes, Center Support Bearings) under powertrain setup guides, where an excellent explanation with diagrams will clear up everything.
