Is this okay? I installed a TH400 with an Ultrabell and it's angled up in the rear. I thought the UB would hit the tunnel first but not mine, I still have space. How much is too much on the tranny angle? Do my u-joints hate me?

 

I'd try to get it closer to zero. Can you take some material out of the rear mount?

(did you measure it off the tailshaft, or the pan?)

 

Yeah I thought it was zero,+1,+2 depending on use!

 

What do you mean depending on use?

 

Two degrees down seems to be the preferred pinion angle...

When you say +6, that sounds like you're describing positive pinion angle of 6 degrees. Definately not desireable, IMHO...

 

I'm talking about the tranny tailshaft is angled up towards the floorboard. I'll check it again but that's what it seems to be. All this stuff is out of your old car too. The tranny, crossmember, and tranny mount. Why would your car be different than mine?

 

B18B1LS1: Are you measuing off the pan or the tailshaft? I used a socket and put it on the slip yolk cap (portion that goes into tailshaft) and then the angle finder on the socket.

 

The angle was off the pan. I'm not sure it's accurate so I'll check off the tailshaft tomorrow. But you can look at it and tell it's positive no doubt.

 

I measured off of my pan and it measured 0 degrees, then I did it off the u-joint cup and it was around -5/-6. You need to measure the tailshaft, not the pan.

 

Agreed. The bottom of the pan is not parallel to the centerline of the driveline. It angles up compared to the driveline.

Another measurement you can use to crosscheck is off the front of the passenger head (if the egr is gone).

 

By use I mean tire,power,drag only car! the more the angle the more hook the tire will get (slicks) or wheel hop (street tires). At least that is how I understand it!

 

2FAST4U: Are you referring to the pinion or the tailshaft?

 

pinion angle!

 

If you have a yoke, put it in the tailshaft and then put a large socket in where the universal joint would sit to get a nice surface for the angle finder.

I would get it to zero, but remember that the angle is relative to how the car is sitting. Is it sitting on a level shop floor? Is the car assembled and at raceweight with the suspension completely loaded? If you need to drop it down, you should be able to space between the crossmember and the frame and lower the rear pretty easily.

 

As far as pinion angle, that is not really true. You want the pinion angle and the engine/trans angle to be parallel under load - the reason is because that is the way to transmit the most power through the driveline (with the least losses).

The difference in pinion angles for different cars is based on the suspension components. So if you have stock rubber bushings that will have a lot of deflection under load (thereby allowing more pinion rotation) you need more angle at rest. If you have poly bushings, you need less pinion angle - and solid rod ends, next to none.

Make sense? Sorry to get off the thread topic a little!