[Gilitin209]

I am currently trying to weld in my motor mounts, so I am making sure the transmission has the correct angle to it. I have the car up on stands, and I am using 2x4 to simulate the driveshaft. The transmission is loosely bolted to the crossmember, and the engine is supported by a hoist. The angle of the driveshaft is 5 degrees up (front higher than back). Currently the transmission pinion angle is 2 degrees up, giving me 3 degrees . Does this sound normal? If it is right, then I believe I just have to make my rear pinion angle about 1.5 degrees up to put everything within specifications. Is any of my thinking wrong? Any advice would be greatly appreciated as Ive never done anything like this and ive prolly spent about 3 hours now just staring at my car with numbers spinning in my head, and I havent even begun prepping the mounts.

 

[Seattle_Mike]

No, it doesn't sound normal. Your transmission and engine is usually slightly tilted down (lower on the transmission end) by 2-4 degrees. Many drag chassis are built for a 0 angle. That being said, if your engine/trans is tilted down, your rear end pinion should be tilted up. (leave the driveshaft out of it) You want a degree or so of difference to keep the U-joints working correclty. For example, if the engine/trans angle is down 4 degrees, your rear end should be pointing up 2-3 degrees. Your car should be sitting at ride height just as it will end up while making these measurements by the way.

Here's a link to a driveline setup guide. http://www.iedls.com/ptsetup.html

 

[Gilitin209]

Im sorry about the wording, by up I mean the engine is higher than the tranny. So as you say, I have a 2.5 degree angle down on my transmission, my drveshaft is 5 degrees down, so my working angle on the tranny pinion is 2.5. Currently the rear pinion is sitting at 3 degrees up, so I am going to get a 1 degree shim to put it at 2 degrees, which will put it within specs when it is under load (according to my logic). As far as ride height goes, i did the best I can. Currently the car is completely stripped down to the medal and only a rolling chassis. I filled the trunk with water jugs and had my roommate and his girlfriend sit in there too to load the rear suspension.

I used the empire driveline and another site to help me figure the math out. So does this sound about right now, cause I think it SHOULD work, but lets be honest, what should work and what actually works on my car rarely happens.

 

[Seattle_Mike]

Sounds like you got it unless geometry changes when you have it all done and sitting ready to go.