pinion angle

[Eugene]

I have a 2008 track dedicated mustang. Replacing the blown tranny with a T56 magnum. What is the usual pinion angle at the diff that track mustangs use? I have seen -2 to -2.5*. Any thoughts?
Thanks.

 

[blacksheep-1]

Ok, well first off, here's the correct way to measure pinion angle ( leave it to the dragster guys to overthink something)

Once that is done, you should be about .. 2 degrees, the dragster guys do more, but that's another suspension story all together.
Now IMO, you should be running a Gt500 stock trailing arm, I'm not going to argue my position, I'm just stating it. So make your adjustments with the lower trailing arms. FWIW, in the not so old days, many guys ran the non adjustable FP lowers with the Gt500 upper, and left it alone because pinion angle in a road course car just doesn't seem to be that critical.
What does seem critical is the engine's crank centerline is at 0, and I'm not sure how you are going to do that without scales.

BTW, the vid is using a dragster type sway bar, which is a sway bay in name only, so disregard all of that.

 

[DaveW]

As mentioned, -2 to -4 is generally the happy zone. It does make a difference in drive off in autocross, but its not a .1 degree change is an adjustment type of deal. More like +1 is worse than -2. If you have camber in your axle, make sure you are adjusting in the range the camber was put in - camber turns into toe as you rotate the housing.

I have also found that thrust angle is pretty important for corner exit traction, probably more important than pinion angle.

DaveW