Has anyone else run into this issue with the Spohn Pro Series Torque Arms? I was installing it yesterday and found that once everything is bolted up, the yoke on the rear end is blocked from spinning by the torque arm mounting bracket.
For reference:
P/N: 301-PSB Pro-Series Adjustable Torque Arm - 700R4/T-5 Transmission - 1982-1992 GM F-Body: Camaro & Firebird, CM Front Mount Type: Spherical Rod End
Rear End: Stock GM 10-Bolt, 3.08 gears, drum brakes








Photos showing the interference between the driveshaft yoke and the bracket/bracket mounting hardware. Not sure how to resolve this, since I would have to grind away the bolt that holds the top rod end of the torque arm.

 

I'd call Spohn and ask them since they built it

 

Isn't there 2 sets of bolt holes? Mine has 2 sets. one set to move it closer to the drive shaft and another set to move it farther from the drive shaft.

 

Yeah, I have it on the set that moves the bracket further away from the driveshaft. It won't fit on the other set with the stock rear end.

 

Do you have a picture where the TA mount connects to the axle? Bottom side is OK as the top would be nearly impossible to get a picture of.

 

Any updates?

 

Judging by those pictures it doesn't look like that unit will work at all. I'd send it back and get my money

 

Well, something is up as Spohn has racers using it.
Not sure where the issue is but it's odd.

Hoping the OP can provide a little feedback.

 

End of discussion

 

Spoke with the Spohn ppl, looks like the pinion yoke is too short on my rear end gear (i didn't know they were made to different lengths?) but luckily i have a rear end that's being rebuilt, will do a test-fit on that one to be sure it clears.

 

Oh, so your original FACTORY part is wrong, and their AFTERMARKET part is right? I guess you shouldn't complain to them then...you should call GM.

 

This looks to be a case where the Spohn part wasn't designed to work with the 10-bolt. After all it is designed for a high HP applications and the 10-bolt, no matter which size ring gear is in it, and /or mods made to it, isn't up to the limit rating of the torque arm. That's more like 9", D60 or at least a 12 bolt rear axle.
I can't say there are different yokes available other than perhaps one for a 1350 u-joint. That would certainly be larger. But in what dimensions I couldn't say.

What spec of new rear? Still a 10 bolt?

 

I haven’t had good luck with a few different Spohn parts fitting in my car. Maybe it’s just me. Dunno

 

I'm not sure why they would tell people on their website that it fits the stock 10-bolt if it wasn't designed for the stock 10-bolt, seems a bit disingenuous. Someone did say they've had issues with fitment from Spohn products though, so not sure. New rear end going in is a 10-bolt out of a 4th-gen (2001 Camaro) which only adds to the weirdness of the Spohn part fitting the 4th-gen rear but not the 3rd-gen rear, if everything between those two chassis in that area really is as similar as i've read about.

 

I didn't see that bit of small print regarding the OEM rear.
I'll be interested to know how this shakes out.
Maybe they are being disingenuous.
Keep us posted.
​

 

I have one on my 9 inch and it has plenty of clearance. And that's on the closer to center bolt hold. I wonder if the bracket
on yours is built wrong?

 

Super late update for anyone interested: I ended up grinding away a little bit of the bracket in order to gain some extra clearance to the Driveshaft/Rear-End Yoke. However, when I had it installed, I found that my car had developed a terrible vibration over 70mph. I tried multiple different things to try and alleviate the issue, from putting new u-joints in, re-balancing the driveshaft, adjusting the pinion angle, trying a new transmission mount, getting the wheels re-balanced, you name it, I tried it. But nothing seemed to get rid of that awful vibration. Has anyone else run into a similar issue running these Spohn Pro-Series Torque Arms, or any crossmember-mounted adjustable torque arms for that matter?

 

This might help:

https://www.thirdgen.org/forums/tran...s-another.html

 

I have a BMR trak-pak torque arm setup in my car - link below. Using it with a Moser Ford 9” rear and Dennys nitrous ready driveshaft. This setup doesn’t mount to the crossmember though. The front bar of the kit is welded between my subframe connectors and the torque arm mounts to that. I don’t have any vibrations.

https://www.bmrsuspension.com/index....&productid=402

 

Have you made any other changes besides having the driveshaft in and out? Maybe a transmission re and re?
FTR: What's your pinion angle set to?

 

Pinion angle was 2.7 coming out of the transmission & 2.6 going into the rear end, and aside from the wheel balance & all the driveshaft work i haven't been able to get anything done. New 10-bolt rear end is fresh rebuilt & has less than 2k on it now so i'm confident it's not from that, transmission is stock from factory & has less than 50k on it. Another note, i have the Energy Suspension poly trans mount in it, since the rubber had way too much give in it (was moving up and down with accel/decel). I have the stock torque arm back in it for now, i have the del-sphere pivot joints to put in if/when i go back to trying the torque arm, waiting on Spohn to send me the correct spacers though...