Hey folks, I'm helping a friend with this undertaking.

We are at the point now where we're trying to get the trans support member measured and fabbed up, but seem to have a horizontal alignment issue with the engine/trans. The tail of the trans is angling slightly more towards the passenger side than should be we think.

We are using the latest Vetteworks LSX adapter plates, and Prothane urethane motor mounts. We took dremels and slotted the holes in the Prothane motor mounts about 1mm to allow us to pull the tail of the trans more towards the drivers side. It helped slightly, but it still doesn't line up as it seems it should.

It was really hard to get any numbers, but we did attempt to calculate the angle by bringing straight lines out from the trans/diff the best we could.

The differential seems to be perfectly straight, and using the Pythagorean theorem on what we measured, the tail of the trans is pointing right at about 2 degrees towards the passenger side away from the diff center line.

We don't know if this should be a concern or not, but want to get it right.

Note that for straightness, we aligned the angle iron on the center seam of the differential, and the level on the center seam of the transmission. It's not perfect, but was the best points of reference we could think of.

This shows the angle discrepancy:




In the below picture, the level is coming straight out of the center of the differential, with the edge on the driver's side being the center line of the diff. It is about 1.5 inches from the driver side edge of the level to the center of the trans output.



Is this angle ok? Does anyone have any better suggestions for more precise measurements?

Any help would be MUCH appreciated!!!

 

Sent you a PM

 

What transmission are you using? That looks like a T56 out of a GTO?



Rick B.

 

You are correct--it's a LS2 and T56 out of a GTO

 

Since the T56 is so much longer than the Muncie or TH350 that was originally intented to fit in the frame the driveline angles are going to look strange. Usually the angle is measured vertically provided that the driveshaft is running straight from the trans to the differential. With the T56 you have to lower the trans to get clearance in the tunnel so the vertical angle is going to appear to be wrong. IMO the side angle from the trans to the differential more than makes up for the almost flat vertical angle and should keep the u-joints from binding or vibrating. We have had the 72 up to 80 MPH or so on the highway and there has been no sign of vibration in the drivetrain. This setup is a LS1/T56, functionally the same as what you have.



Rick B.

 

Thanks for the info Rick!! So am I correct in assuming that you experienced this same side angle?

Additionally we were planning on trying to get the trans mount setup before we put the body back on. You seem to be saying that the proper vertical angle can't be achieved with the trans as well, so is it better to finalize the trans mount after the body is on so that we can get the trans as high as possible?