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Discussion Starter #1
We now have a complete bulletproof drivetrain available for the GTO. We found the OE differential to be plenty strong but the axles, CV's and driveshafts are failure prone. After speaking with various Australian companies, it was determined the factory components fail in the following order:
1)Driveshaft - usually the rubber joints will break when drag racing once the car dips below 1.70's in the 60 foot mark.
2)CV Axles - If the shaft doesn't break at the transition point, the inner CV joint breaks.
3)Axle Stubs - These rarely break before the other components but if you upgrade the other components, these become the next weak link.

Our 1 piece driveshaft is not only made from chromoly, it's also an inch larger in diameter. Instead of reinventing the wheel, we use proven Mark Williams billet front drive yokes and the driveshaft gets forged 1350 series u-joints front and rear. A custom machined drive hub is also provided with the driveshaft to adapt the Australian rear to traditional U-joint standards. This hub is machined from billet and then hardened.

Our Heavy Duty CV axles use custom billet CV cages and the shaft itself is made from 300M material, the strongest axle material available.

Our Stub Axles are also CNC cut from 300M billet and are a direct replacement for the factory axles.

All three products are now available for shipping. For more images and product detail, go HERE.

 

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Member #804
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I think I choked for a second when I saw the price, still these products are good quality right?
 

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Discussion Starter #3
GMH GTO said:
I think I choked for a second when I saw the price, still these products are good quality right?
We used the best of everything in these parts. If it's not billet 300M material, it's hardened 4340 or chromoly. Even if money was no object, you could not build these products any better. 300M alloy is the same alloy used in Top Fuel car axles, hubs, etc. and is the strongest driveline alloy available. If anything, the parts may be overkill for the majority of applications.
Sometimes companies inflate their pricing in niche markets but I can assure you that is not the case here. The price is justified in material, quality, and design.
 

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DOG
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I had a chat with them about their stuff that was coming and I agree that I nearly choked on the driveshaft price (About two weeks ago) but seeing it up close, its a MUCH better component then what we have stock and takes care of a lot of other issues that the rubber biscuits. If you are building a serious machine, I highly recommend their stuff.
 

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Oh my f*ck!
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I know BMR is not overcharging for this stuff. It's quality product and I can't WAIT to get my hands on their stuff. I had to add this component to my wish list when I read about it this morning. I'm up to $17k. :gr_jest: It's too bad it'll be next year before I can really start working on the list though.

Oh, and if anyone is curious, here is a good page of information on the 300M Alloy that is used in these components. Chem Es, eat your heart out.
 

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speed_demon_freak said:
What about the install? Is most of it just some simple swaps or would you recommend a professional?

Install looks to be fairly simple.
If you have any mechanical backround you should have no problems.

The hard part is getting the cash for that upgrade :eek2:
Looks like great quality stuff.
I would consider it if I was willing to get a divorce shortly their after :gr_jest:
 

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Price may be hard to swallow, but this is what it takes to run with the big boys. You can't just bolt up slicks to a car and not expect to break something. I'm happy that the diff is not weak. THe whole fbody rearend was made of glass practically and required at least a $2000 12 bolt rear end.

With the H/C packages available, N20, and blowers coming out you know someone is gonna do some serious GTO racing. Looks like solid products, BMR :thumbs:
 

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Discussion Starter #11
speed_demon_freak said:
What about the install? Is most of it just some simple swaps or would you recommend a professional?
Installation isn't too bad. You could do the stub axles and CV shafts in about 2 hours with simple hand tools.
The driveshaft requires a little more effort to install it. GM didn't leave much room in the back tunnel area so going any larger at all on the driveshaft requires a few modifications. First, stock mufflers won't clear unless you notch them. Just about any aftermarket exhaust that uses round mufflers will clear. There is also a seat belt bolt that needs shortened. Provided your exhaust clears, you could do all 3 in about 3-4 hours on a lift.
 

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SOLD-04 & 06 Torrid Red GTO's
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Brett (at BMR), for the driveshaft, what is the calculated critical speed with an M6 and A4 with both 3.46 and 3.91's? Either mph or rpm...thanks and take care.
 

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RUQWIKR said:
Brett (at BMR), for the driveshaft, what is the calculated critical speed with an M6 and A4 with both 3.46 and 3.91's? Either mph or rpm...thanks and take care.
Is this the RPM @ which the driveshaft shatters or something?
 

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Member #804
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how are the stub axles held in? Do you pry them out, held in with a ring? Or are they a C clip.

You guys had problems with the LSD, you gonna keep going with a OE LSD or go to a KAAZ?

Is BMR going to offer gears?

thanks
 

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...and former GTO owner.
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BMR
Now that you have changed the drive shaft, CV axels and stubs, including a differential that went, would you say the tranny would be the next weakest link? What have you done to it to make it last so long? Also what diff did you end up getting?
 

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GMH GTO said:
how are the stub axles held in? Do you pry them out, held in with a ring? Or are they a C clip.

You guys had problems with the LSD, you gonna keep going with a OE LSD or go to a KAAZ?

Is BMR going to offer gears?

thanks
I have the same question, although without trying to start another, off-topic debate, I wonder if BMR has had experience with a Torsen T2R differential?

If you are not planning on offering a LSD replacement unit, is it possible for you guys to tell us what the dimensions of the OE LSD?

Like you guys, I am not afraid of the OE LSD breaking, I have already worn out the limited slip characteristics by doing some autocrossing.

Thanks!

Jim
 

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Discussion Starter #17
GMH GTO said:
how are the stub axles held in? Do you pry them out, held in with a ring? Or are they a C clip.

You guys had problems with the LSD, you gonna keep going with a OE LSD or go to a KAAZ?

Is BMR going to offer gears?

thanks

I have nothing against the KAAZ unit but we are going to wait and see what else becomes available. With such a small diameter ring gear, their isn't much room for clutches of any size. This ultimately will be the limiting factor for any aftermarket posi unit unless someone develops a true locker. The KAAZ unit is definitely more practical for autocross and road racing and will even survive frequent drag racing on modified cars but for our purpose a locker is more appropriate. For the time being we will be using a custom machined spool to positively lock the axles. Eventually we may switch over to a Harrop 9" or 12 bolt diff if a locker doesn't become available but I don't see that happening unless the price drops drastically.

The stub axles are very simple to replace. Once the CV axles are unbolted, the stub axles can be popped out of the differential. They are held in place by a spring clip that stays attached to the axle. On a lift with air tools, you could replace a set in about an hour.
 

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Discussion Starter #18
[QUOTE='91 Formula]BMR
Now that you have changed the drive shaft, CV axels and stubs, including a differential that went, would you say the tranny would be the next weakest link? What have you done to it to make it last so long? Also what diff did you end up getting?[/QUOTE]

We have plenty of customers running 10's on 4L60's with nothing more than shift kits. If a shift kit is installed before the clutches get too worn and the line pressure is increased with tuning the tranny will survive for a while, especially when combined with the increased strength of the 04+ 4L60's. We have made over 80 dyno pulls and 30 drag strip passes so far (knock on wood). I can tell you one thing, we will definitely find the next weak link once the new motor goes into the project car.
 

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BMR Fabrication said:
We have plenty of customers running 10's on 4L60's with nothing more than shift kits. If a shift kit is installed before the clutches get too worn and the line pressure is increased with tuning the tranny will survive for a while, especially when combined with the increased strength of the 04+ 4L60's. We have made over 80 dyno pulls and 30 drag strip passes so far (knock on wood). I can tell you one thing, we will definitely find the next weak link once the new motor goes into the project car.
New motor?
 

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SOLD-04 & 06 Torrid Red GTO's
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Once again...Brett (at BMR or whomever), for the driveshaft, what is the calculated critical speed with an M6 and A4 with both 3.46 and 3.91's? Either mph or rpm...thanks and take care.
 
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