Speedtech 12bolt Torque Arm questions

[JuStBlAzIN]

Hi Yall! I am getting read to order my Rear suspension and I am thinking of the 12 bolt kit from Speedtech.

I already have all the items to build my 12 bolt. Gears, axles, posi unit, wilwoods. It is ready to be sent out to powder coating.

I am thinking of going with the Speedtech 12bolt rear torque arm kit. Are there any draw backs of going with this kit on a 12bolt over a 9"? Has anyone had the brackets welded on to a 12bolt?

1969 Camaro convertible
Front Speedtech Protouring Subframe
ls3 (500hp) with a 4 speed automatics.

[raustinss]

As a fabricator I am interested in this , under load the carrier is "pushed" back thru the back of the rear axle housing . Hence why some people use a girdle style cover. Having said that I dont think making some sort of bolt on mount on the back side of the housing would be ideal . So now this leaves a weld on mount to the bottom of the axle housing , which is cast steel. This brings in some new issues .Im sure a properly designed and properly welded set up would work . Curious to see this one work out . I had considered this at one point myself

[JuStBlAzIN]

I spoke to Speedtech and was recommend the 9" with their brackets already welded on. Not sure i want to spend another 3500 for a new Axle considering i already have everything purchased for my 12 bolt, ontop of the 3500 or so for the suspension kit.

the 12 bolt uses a front pinion clamp/attachment and a plate that gets sandwiched between the cover and the housing itself. I spoke to my suspension/Frame specialist, and he said he can weld onto the tubes. But would require the car to but on his frame alignment machine to make sure its properly aligned, driveshaft angel is correct before welding.

Still weighing the option of the 12 bolt over the 9". Wanted to see if other have done the 12 bolt.

[dontlifttoshift]

Given a choice I would take a 9" over any other rear end for a torque arm installation in a non stock application.

[Jk918]

You could sell your 12 bolt to recoup the some of the cost. I am looking into the G-comp rear set up as it comes with the 9in housing as part of the package.

[raustinss]

Well if it could be welded to the axle tubes keep in mind you would need either an alignment bar in the housing while you weld or, you would probably need the axle straightened after the welding process. That can be done 2 ways .. sheer force aka throw it in a press or heat shrinking the axle tubes

[chevelletiger]

I'm in the process of installing a SpeedTech 2nd gen camaro TA on my 72 chevelle,like you I already had a 12 bolt I put money into,so the 9 inch is outta the question, SpeedTech makes the ring,I made my own,as well as im making he billet mount.
I got the TA used off of someone, and I'm fabricating it to the chevelle.
It's funny how speedtech said to get the 9inch if you already have the 12 bolt?

As for the load on the ring and the bolts,I spoke with my engineer ex Co worker,and he was saying the 2 3/16 tabs welded to the underside of the 9inch housing, weren't any stronger that the 12 bolts holding the ring on.
I'll be the test dummy!

It should be fine I know roger runs the 12 on his TA 69 camaro.
Talk to him or Blake about it there pretty helpful if you call them.

[raustinss]

Hmm well thats good that an engineer did some math for everyone. Kinda cool that 2 people are working on this at the same time

[chevelletiger]

Right.
Except I'll have to make everything except the torque arm ��

[CSG]

In the mustang world I have seen a few reports of issues (leaks) with the ring style mount that attaches at the bottom to the TA (Griggs Racing). If you have room you may consider a ring mounted to the TA more like how BMR does it.

[chevelletiger]

CSG.
I thought about something like that upper ears though.
I'll try mine with the plate for now.
Well see how it goes.

[JuStBlAzIN]

I'm in the process of installing a SpeedTech 2nd gen camaro TA on my 72 chevelle,like you I already had a 12 bolt I put money into,so the 9 inch is outta the question, SpeedTech makes the ring,I made my own,as well as im making he billet mount.
I got the TA used off of someone, and I'm fabricating it to the chevelle.
It's funny how speedtech said to get the 9inch if you already have the 12 bolt?

As for the load on the ring and the bolts,I spoke with my engineer ex Co worker,and he was saying the 2 3/16 tabs welded to the underside of the 9inch housing, weren't any stronger that the 12 bolts holding the ring on.
I'll be the test dummy!

It should be fine I know roger runs the 12 on his TA 69 camaro.
Talk to him or Blake about it there pretty helpful if you call them.

What are their user names?

[Jimmy Sean]

I have the 12 bolt Speed tech torque arm and have had the pinion mount come loose, I had to replace the mount once. If I had to do it again I'd go 9".

[jetmech442]

I just throw out there that fabricating/welding on a Fab9 is probably the easiest thing in the world. We cut the upper ears off and fab'd/welded in a 3 link in an afternoon.

[JuStBlAzIN]

I have the 12 bolt Speed tech torque arm and have had the pinion mount come loose, I had to replace the mount once. If I had to do it again I'd go 9".

Any chances you can send me some pictures of the set up?

[chevelletiger]

Same^^ could you send me some pictures please,and infor what you did to the pinion mount,as I'm making my own pinion mount.

I would do the 9 inch also, but I have alot invested in the 12 bolt,and I'm building a 9inch with a floater and Tci TA on the 68 mustang coupe.

[Jimmy Sean]

https://speedtechperformance.com/wp-content/uploads/2023/01/10300_Torque-Arm_67-69-F-Body_68-74-X-Body.pdf

Pages 13 & 14

I only have pictures of the failed mount. (one of the bolts came loose and evacuated)

206133206134206135

[chevelletiger]

JIMMIY SEAN.
Sent you a pm.