im trying to adjust my spohn ta correctly and im not positively sure i have it right. ive done the search and read the instructions closely. i measured +4 degrees on the driveshaft and -2 on the pinion so i adjusted the pinion to -4 thinking this would give me 0 degrees true pinion angle. is this the correct way of adjusting? i noticed after i made this adjustment that the driveshaft angle was now about +1 degree.i havent driven it yet with this adjustment.
ive got about 100 miles on my 12 bolt and the pinion seal is leaking bad. i also noticed that when i was on the highway if i stabbed the gas real quick and let off real quick id get a thump i could feel and hear. the torque arm is hitting the bottom of the car back by the rear housing. to be exact, theres the 2 huge bolts that go through the rod ends and i thought it was the upper nut hitting but its that top corner of the ta bracket. there are about 5 dents just above it on the car from it hitting. im guessing i had to much positive degrees wich was allowing the ta to move up that far to make contact with the bottom of the car. the 12 bolt isnt really noisy gear wise but i did feel a rumble through out the car on the highway. im pretty sure the clunk is not the ds bottoming out because i just had a new one made that was 1 3/4 inches shorter than my aluminum one. any help would be appreciated. kev

update: i drove up to autozone to get more gearlube and it felt much better. havent taken it on the highway yet though to try to make it thump again. i had lost 1 1/2 quarts gearlube through the pinion seal.

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355,ported heads,forged pistons&rods,cc 220 224 cam,triflo,ed wright,moser 12 bolt 3.73,spohn ta,old tune->345rwhp @ 5200 rpm 453ftlbs flywh torque @ 4500 rpm(should have tested to higher rpm on hp)

[This message has been edited by kev93z28 (edited August 17, 2002).]

[This message has been edited by kev93z28 (edited August 17, 2002).]

 

The torque arm bolts go from the top down.

Recheck the pinion angles after changing them.

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Stephen's racing page
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87 IROC SuperPro race car
461 big block
Best ET on a time slip: 11.418
Best MPH on a time slip: 117.01
Best corrected ET: 11.051

Altitude corrected rear wheel HP: 468
Best 60 foot: 1.595
Member of the Calgary Drag Racing Association

 

i have the moser 12 bolt with 4 bolts that dont run all the way through. i checked them and they are tight, i put locktite on them. thnaks for the reply though. kev

 

I've got instructions on setting your pinion angle, at http://www.go-fast.org/z28/pinionangle.html

Dave

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1997 LPE 383/n2o Camaro Z28 Convertible
12.39@112.2, 1.76 60' (na) 11.27@124.6, 1.76 60' (n2o)
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