IRS/Diff/halfshaft angle

[andrewb70]

Originally Posted by 240RR

Well, that is what I also thought and I started that way and got the diff in a fixture based on the halfshaft angle and pretty much OEM 350Z. Then realized the engine will sit a lot lower and the driveshaft will run uphill to the diff and I guess that is not good...
I can't have it both ways and something is gonna have to run at a different angle...just not sure where to compromise?

Halfshafts at correct OEM angle equals driveshaft running uphill to diff
Driveshaft at correct OEM angle equals halfshafts running downhill to diff

This can't be so difficult as it would be the same proplems racecars would run into with drastically lowered ride heights....It about has to be the halfshafts running downhill to the diff and focus on maintaining proper driveshaft angle...I THINK????

What kind of car are you working on? Can you raise the back of the transmission so that it points at the diff? That will fix your driveline angle problem.

Andrew

[240RR]

Originally Posted by andrewb70

What kind of car are you working on? Can you raise the back of the transmission so that it points at the diff? That will fix your driveline angle problem.

Andrew

At this point I can do just about anything as I just started on the chassis. Tube chassis 240z with 350z engine and 6 speed.
I read that all mfg pretty much drop the rear of the engine about 3 degrees to get the angles or something....if it is not a problem raising the back a little then that would work.

Did a little this morning and with the diff in its OEM position and halfshafts in proper angle...hub in a fixture...I have the following rough measurements.

Crankshaft centerline 11-1/4" (engine at level...if I drop the rear 3* then the trans tail shaft will be approx 2" lower.
Diff pinion centerline 12"

not sure this is enough info as I do not have the tranny yet but do have the dimensions so I can come really close to figuring out the angles and then the driveshaft length and Working angles.

The crankshaft centerline is about the only thing I can't really change...everything else is in play at this time. Lower diff, angle engine...I am just struggling on what to work from.

I kinda think I should lower the diff if it is OK for the halfshafts to run a little downhill to the diff...I think I could get my working angles OK on the driveshaft if I lower the diff. Really this is not much different than the guys that race 350z's...they are all lowered a good amount and they have to have the same issue with the halfshafts running downhill to the diff???????

I will be glad to get this all sorted out...arrrgghh