danespann

Car currently has a KTRE 12-bolt with the tapped, non-through-style mounting holes and keeps breaking the torque arm mount on my BMR adjustable torque arm.

I have the kit that fills the holes in the arm to make them the right size and use red loc-tite, but the bolts find a way to escape. It used to take a month for them to come out, but now they last maybe a week.

Question is, can I use a stock torque arm with the 12-bolt? Is anyone on here doing it? If so, I will buy one for a few pennies and sell my BMR.

The car is a daily driver and occasionally gets autocrossed. Not making much more than stock power. I'm just tired of always replacing $60-$100 mounts or welding it and having to constantly be under the car when it's 120 degrees out.

I searched for like an hour and couldn't find anyone with a 12 bolt and stock arm. Maybe that's because their setups don't break. Thanks.

farmington

iTrader: (14)

seems like there is a space between the torque arm and the rearend where it attaches or is that just how it looks in the pictures?

danespann

It looks that way because it is bent in these pictures after the top bolts came out for the bazillionth time while driving down the highway. There was no space when the bolts were installed before, even after it was welded. This is my third mount I believe. I was not about to drop money on a 4th, so this one got welded.

UMI Sales

iTrader: (1)

As long as this Moser bolt kit with the inserts is used we never have a failure issue with ours.

http://umiperformance.com/catalog/in...roducts_id=742

If the inserts aren't used with a Moser it's 100% failure.

http://umiperformance.com/catalog/in...roducts_id=470

If you need a mount give me a call here at the shop and i can hook you up.

Craig

BMR Sales2

iTrader: (40)

I see this many times with Moser style 12 bolts. The bolt design does not provide enough clamping force to locate the arm to the housing and allows the rear to shift in the mount and elongate the holes and becomes a self-complicating issue. Usually it stems from the bolts working their way loose. I normally recommend using the upgraded ARP hardware torqued to higher spec, a lock washer and some loc-tite for added insurance

danespann

I actually have the UMI kit with the inserts installed, but this is a KTRE rear, which uses M12 1.75 Bolts, so I used some that I already had because the ones from the kit didn't fit.

The top front bolt came out again less than a week (4 days) after installing the inserts with red loctite on the bolts and the rear top bolt, while it stayed in, ripped the back of the mounting bracket off the BMR torque arm.

I thought the issue was going to be fixed because everything was right this time... Inserts, lock washers, and red loctite. Just can't figure out why the bolts are ejecting themselves at this point. Next step may be safety wire and/or welding the mounting bracket to the diff out of frustration.

I haven't heard of anyone having this issue with a stock torque arm, so I think I will give it a try if I can find one. Looks like the whole arm is less than just a replacement bracket and I don't need the adjustment because the rear of this car is stock height.

BMR Sales2

iTrader: (40)

The reason noone has the issue with a stock arm is because it is so much thinner material it doesn't require the clamping force to keep it tight to the axle. Our arm uses 1/4" plate steel instead of the stock one which is maybe 1/8", plus with the welded joints and shaping, it is much harder to clamp to the axle. What grade are the bolts you are using and what torque are you running them to?

danespann

The bolts are stamped 10.9 and are metric, so they should be equivalent to a standard grade 8 bolt from what I have read. I torqued them with a 1/2 inch breaker bar until I couldn't turn them more or felt like I was going to break something. That made it seem flush to the differential. So, maybe 140-150 ft/lbs.

The first time I installed the bracket, I ground some material off the differential to make a flatter mounting surface so the bracket would sit flush at the back. After that install, it lasted like 8 months with me tightening the bolts once a month without the hole-filling kit.

Both you and UMI make great stuff and have excellent service, which is why I buy products from both. Just thinking that the stock part will hold up fine in this street/autocross application and this arm can be put to use on a friend's car with a 10-bolt where it will get along with the diff a little bit better until his stock rear itself explodes.

BMR Sales2

iTrader: (40)

As an alternative, I do have and upgraded torque arm bracket that is made of 3/8" material and is much heavier duty. If you wish to go that route, let me know and I will see what I can do on it for you

Jennifer 72 camaro

my son has a 94 m6 with a 12 bolt and he kept breaking his BMR torque arm, like you sasid it would come out after a week or two so what he did when it broke off the last time he welded plates to it to reinforce it then used some bolts with lock washers and lock tight let it sit over night and hasnt had a problem since and he drag races alot and dailys the car hope you get it fixed soon!