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View Full Version : Quick Driveline Angle Question

LTb1ow
05-07-2015, 01:30 PM
4th gen fbod chassis, adjustable torque arm.

Gonna measure trans angle, and mimic that angle with the rear end but opposite. So if trans is 2* down, rear end will point 2* up?

(then there is some adjustment for "preload" in the angle but just wanna set it for 100% street driving at the moment)
sweetbmxrider
05-07-2015, 05:26 PM
Yes
LTb1ow
05-07-2015, 08:53 PM
Welp, on first glance, BMR X member and or poly mount dun goofed.

Rear end is 0*, or parallel with car.
Drive shaft angle is 2* going up from rear to trans.
Trans mount is 3* up into car.

So the U joint at pinion is a delta 2* and the U joint at trans is delta 5*.

Prob enough to make noise no?
The_Bishop
05-08-2015, 06:00 AM
Wait, you're saying the transmission is aimed up in the tunnel?

I usually check the engine angle via the front of the cylinder head surfaces, where the accessories mount. those surfaces are 90* to the crankshaft. That gives me the engine/trans angle.
LTb1ow
05-08-2015, 07:06 AM
Wait, you're saying the transmission is aimed up in the tunnel?

I usually check the engine angle via the front of the cylinder head surfaces, where the accessories mount. those surfaces are 90* to the crankshaft. That gives me the engine/trans angle.

Yes. Points up from the ground into the car, 3*

I am gonna try to see what I can shim it down to without angering the solid mounts.
sweetbmxrider
05-08-2015, 07:20 AM
Ya I wonder where the issues is....and could you cut the trans mount area to lower the tailshaft?
LTb1ow
05-08-2015, 07:42 AM
Ya I wonder where the issues is....and could you cut the trans mount area to lower the tailshaft?

I am hoping/banking on the trans mount shim being at fault here.

Otherwise, I will see how much of a shim distance I need on the trans mount and then make up something at work.
The_Bishop
05-10-2015, 08:33 AM
You have the poly mount with the shim/spacer that goes between it and the mount, yes? If so pull it out and see what you have.
LTb1ow
05-10-2015, 09:01 AM
I did, yanked the shim from the mount. Seemed to drop the trans back to a good angle. Will need to work on it on a lift at this point.
sweetbmxrider
05-10-2015, 09:30 AM
****.
ThoR294
05-11-2015, 02:26 PM
What issue are you having?
Blackbirdws6
05-11-2015, 03:22 PM
His car wants to shake itself apart while in 1st and 2nd gear.
LTb1ow
05-11-2015, 04:04 PM
Solid motor mounts BRAH!
Blackbirdws6
05-11-2015, 04:49 PM
3rd gear was smooth. No excuse for 1st and 2nd non-sense.
sweetbmxrider
05-11-2015, 08:02 PM
3rd gear was smooth. No excuse for 1st and 2nd non-sense.

Maybe the position of the shifter is effecting the cog?