pinion angle again

pinion angle again - 04/16/10 02:16 AM

maybe somebody can help me..please..heres what i have.....with the car jacked up and sitting on 5 blocks under each wheel with the car on the suspension .....drive shaft out and measuring the angles of the trans is -4 and pinion is plus 4.....so what i am thinking is i am at 0 ...right.....with the driveshaft in and measuring angles at top of shaft its plus 1 and by the pinion on the shaft its plus 1....so thats zero ...right.....so i need 5 to 7 degrees down....right......so what do i do to get 5 to 7 degrees down..nose down the rear??5 to 7degrees??....i lowered the 727 to make room for the carbon fiber trans shield and i just installed a gear vendors overdrive which is why the trans is minus 4 degrees

Posted By: Joshs68

Re: pinion angle again - 04/16/10 02:35 AM

Thats how I measured mine, crank centerline was 3* down, pinion was 3* up . I called that zero. If those angles are the same the drivshaft angles will be equal but opposite. I installed a shim under my rear pads to drop the angle of the rear to -1* down or -4* total. I think its correct. It made my driveline vibration go away completly and took care of any spring wrapup. hope that help Im not a pro but that what I did.

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 02:44 AM

thanks josh....i have shims but was thinking of replacing and welding in new spring perches..have them too...just confused and trying to figure this out

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 02:58 AM

i didnt tell you its a 68 roadrunner/dana 60 with ss springs/mark williams driveshaft if this helps....thanks

Posted By: 70Cuda383

Re: pinion angle again - 04/16/10 03:44 AM

shims or cut the mounts and re-weld. either will work. just be careful with the welding, don't want to warp an axle tube.

as far as how much angle on the pinion you need...I've learned that there is no magic number after reading everything online. some will say 3-4 degrees, others say 5-7. some will say whatever it takes to get 0 degrees under WOT with spring wrap up at it's max.

do you have a vibration now? I'd say drive it, see how it feels, and adjust as needed from there.

Posted By: Cab_Burge

Re: pinion angle again - 04/16/10 03:44 AM

Quote:

thanks josh....i have shims but was thinking of replacing and welding in new spring perches..have them too...just confused and trying to figure this out

Best bet is to remove and replace the spring pads,reposition the rear end housing with the pinion nose down to what angle you want and tack weld it in place. Remove it for the final welds, you might want to think about placing a strap, 3/16 to 1/4 thick by one inch wide,across the rear end housing from the ends of the spring perches to the other end as a brace, like a V. Forget the adpater shims

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 04:29 AM

Quote:

shims or cut the mounts and re-weld. either will work. just be careful with the welding, don't want to warp an axle tube.

as far as how much angle on the pinion you need...I've learned that there is no magic number after reading everything online. some will say 3-4 degrees, others say 5-7. some will say whatever it takes to get 0 degrees under WOT with spring wrap up at it's max.

do you have a vibration now? I'd say drive it, see how it feels, and adjust as needed from there.

well i guess i am at i think plus 3 so if i nose down the pinion minus 9 degrees that would set me at minus 6....would this be the right way of doing this
i havent driven the car yet because i just installed the gear vendors overdrive and i ordered a shorter driveshaft .....i am just trying to get this set right.....its mostly a street car but it does see the strip 4-5 times a year.....i usually set the pinion snubber 1 inch from the floor

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 04:36 AM

Quote:

Quote:

thanks josh....i have shims but was thinking of replacing and welding in new spring perches..have them too...just confused and trying to figure this out

Best bet is to remove and replace the spring pads,reposition the rear end housing with the pinion nose down to what angle you want and tack weld it in place. Remove it for the final welds, you might want to think about placing a strap, 3/16 to 1/4 thick by one inch wide,across the rear end housing from the ends of the spring perches to the other end as a brace, like a V. Forget the adpater shims

these danas are pretty bullet proof right?you really think i need a brace?....what happens with the cover? do you think i should nose down the pinion minus 9 degrees to get it to minus 6?

Posted By: DoctorDiff

Re: pinion angle again - 04/16/10 12:14 PM

If the pinion centerline is parallel to the transmission centerline, install a pair of 3 degree angled wedges, or cut he perches off and roll the pinion downward 3 degrees. This will yield a true, 3 dgree negative pinion angle.

Posted By: moparniac

Re: pinion angle again - 04/16/10 12:15 PM

Quote:

Best bet is to remove and replace the spring pads,reposition the rear end housing with the pinion nose down to what angle you want and tack weld it in place. Remove it for the final welds

this is what I did and I boxed my perches in!

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 01:15 PM

thanks guys for all your help

Posted By: Hemiroid

Re: pinion angle again - 04/16/10 01:29 PM

Quote:

these danas are pretty bullet proof right?you really think i need a brace?....what happens with the cover? do you think i should nose down the pinion minus 9 degrees to get it to minus 6?

He was talking about adding a piece of flatstock that is wrapped around the axle tube in a "u" shape to support the ends of the perches.

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 02:27 PM

Quote:

Quote:

these danas are pretty bullet proof right?you really think i need a brace?....what happens with the cover? do you think i should nose down the pinion minus 9 degrees to get it to minus 6?

He was talking about adding a piece of flatstock that is wrapped around the axle tube in a "u" shape to support the ends of the perches.

thats a good idea....now thats clear....thanks

Posted By: Joshs68

Re: pinion angle again - 04/16/10 06:32 PM

Quote:

Quote:

shims or cut the mounts and re-weld. either will work. just be careful with the welding, don't want to warp an axle tube.

as far as how much angle on the pinion you need...I've learned that there is no magic number after reading everything online. some will say 3-4 degrees, others say 5-7. some will say whatever it takes to get 0 degrees under WOT with spring wrap up at it's max.

do you have a vibration now? I'd say drive it, see how it feels, and adjust as needed from there.

well i guess i am at i think plus 3 so if i nose down the pinion minus 9 degrees that would set me at minus 6....would this be the right way of doing this
i havent driven the car yet because i just installed the gear vendors overdrive and i ordered a shorter driveshaft .....i am just trying to get this set right.....its mostly a street car but it does see the strip 4-5 times a year.....i usually set the pinion snubber 1 inch from the floor

if you are at plus 3* now and that is parallel with the crank center line then consider that zero. so if you shim for zero on your gauge then that would be 3* down

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/16/10 07:48 PM

Quote:

Quote:

Quote:

shims or cut the mounts and re-weld. either will work. just be careful with the welding, don't want to warp an axle tube.

as far as how much angle on the pinion you need...I've learned that there is no magic number after reading everything online. some will say 3-4 degrees, others say 5-7. some will say whatever it takes to get 0 degrees under WOT with spring wrap up at it's max.

do you have a vibration now? I'd say drive it, see how it feels, and adjust as needed from there.

well i guess i am at i think plus 3 so if i nose down the pinion minus 9 degrees that would set me at minus 6....would this be the right way of doing this
i havent driven the car yet because i just installed the gear vendors overdrive and i ordered a shorter driveshaft .....i am just trying to get this set right.....its mostly a street car but it does see the strip 4-5 times a year.....i usually set the pinion snubber 1 inch from the floor

if you are at plus 3* now and that is parallel with the crank center line then consider that zero. so if you shim for zero on your gauge then that would be 3* down

well i went for the #3 shim....so now i have plus one at the pinion and minus 4 at the trans.so now i have minus 3....that should work.....i want to thank all of you that help me

Posted By: GEORGE68HEMIRR

Re: pinion angle again - 04/26/10 12:18 AM

WELL NOW I HAVE A VIBRATION AROUND 45-50 MPH....do i lower the pinion more??