r180 moustache bar and halfshaft alignment

[madkaw]

Trying to do some searching on proper moustache position for the diff based on model years.
There has been a lot of threads on the diff whine -especially with the early models with the r180 diff. I guess I have read that the moustache bar was actually was flipped around to pull the diff back to line up the halfshafts(make them more perpendicular to the diff) to help with diff noise.
Looking at the 8/71 in my garage the halfshafts do angle a lot from the diff -BACK- to the axles.
It would seem that if the bar was flipped the angle would be much closer to 90 degrees.

On my car 9/71, I can't recall what was the stock position. I do have a r180(subaru r180) in my car and I set mine up very close to 90 degrees, I am running a RT mount. No diff noise-but it is from a 2003 STI

anyone have knowledge on such subject???

[240dkw]

Steve I think that the bar is different, it is bent to move the diff back. You will need the longer driveshaft to make up the different lengths. As well, the arrestor bracket, the back transfer brace and front diff bracket are all different.
Dan

[John Coffey]

The diff was moved back more for vibration then noise. If you have a diff whine check your front diff mount to make sure its not worn with metal to metal contact anywhere. Also, check the front diff cross member for cracks.

[madkaw]

Thanks JC .
The noise is a cross between whine and rubbing- hard to describe- but increases with speed.
I am changing the diff as we speak to eliminate that.

[Mikes Z car]

On the 8/71 240Z (HLS 038??) I used to have the diffy was in the later further back position. Why I remember that small detail on a car I last saw 27 years ago in Sacramento I don't know other than the fact that I really liked that car, my all time favorite along with the 70 I have now..

[madkaw]

Maybe had a r200 in there?

[Mikes Z car]

Well I bought the 1971 240Z in 1976. There were no signs of changes/upgrades that I recognized. I hadn't thought of the possibility of an r200, back then didn't know they existed.

[geezer]

Up to 06/71, end of the '71 model year part number 55450-E4101

From 07/71 to 07/73 the '72 model year part number 55450-E8300
My scanner is down, Dan is correct, there are 8 different modified parts shown in order to move the diff rearward 1 1/4". The illustration doesn't show the mustache bar being flipped/reversed though it is shaped differently. The pic below is an R200 pulled from my '70z barn find. That mustache bar is reversed.