I've got the 8 3/4 rear sitting in the perches with about 3 degrees down on the trans end of the driveshaft and about 4 degrees up on the diff end of the driveshaft giving me the one degree difference I think I'm looking for. How much spring windup should I expect and adjust for on a "mostly' street driven 440, 727, 4.10:1 gears?
super stock spring windup question
- Thread starter csilver
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List a engine /transmission/ converter (?)\clutch(?) / chassis (?) combination , let's start, there
I know this is a lengthy post, but I need to do this correctly so I am asking for your help. I am about to weld the spring perches on a narrowed 8 3/4 sitting on SS springs. The more I read about it, the more confusing it becomes. Please tell me if I have this right:
1) Front and rear "working u-joint angle" should be almost equal and opposite to minimize vibration and keep the needle bearings moving.
2) Operating u-joint angle should be kept under 3*.
3) "Nose down" refers to the pinion angle relative to the driveshaft tube angle, not the ground.
4) "UP" and "Down" refer to the slope of the component starting from the front of the car ending at the back of the car. Example, My 67 Dart GT 440 engine is "down" 3.2*, the driveshaft tube is "down" 5* and lastly, the pinion is "down" 2.7*
If this is all correct, then my front u-joint angle is 1.8* and the rear u-joint angle is 2.3*. This would give me the 1/2* difference between the two if it weren't for the fact that under hard acceleration I know the springs will wind-up, I just don't know how much wind up to expect/allow for.
It is a mostly street, occasionally strip vehicle with a mild 440, 3200 stall 727, 4.10 posi, fat rear tires. Can you experienced folks please help me?
1) Front and rear "working u-joint angle" should be almost equal and opposite to minimize vibration and keep the needle bearings moving.
2) Operating u-joint angle should be kept under 3*.
3) "Nose down" refers to the pinion angle relative to the driveshaft tube angle, not the ground.
4) "UP" and "Down" refer to the slope of the component starting from the front of the car ending at the back of the car. Example, My 67 Dart GT 440 engine is "down" 3.2*, the driveshaft tube is "down" 5* and lastly, the pinion is "down" 2.7*
If this is all correct, then my front u-joint angle is 1.8* and the rear u-joint angle is 2.3*. This would give me the 1/2* difference between the two if it weren't for the fact that under hard acceleration I know the springs will wind-up, I just don't know how much wind up to expect/allow for.
It is a mostly street, occasionally strip vehicle with a mild 440, 3200 stall 727, 4.10 posi, fat rear tires. Can you experienced folks please help me?
The MP suspension book says pinion should be 5-7 degrees nose down in relation to the drive shaft. Makes it pretty simple.
Yes.
Keep in mind, that's not the pinion angle. That's the pinion angle in relation to the drive shaft. There's a difference.
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