700+hp LSD options?

[Thorfmxrdr88]

I have a built e82 1M clone that's lacking lsd and strong enough axles to support the power it's making. Before winter hit (I live in the #1 snowiest city in the nation) the car put down 633whp on a mustang dyno, with about 8 more lbs of boost left. I'm looking to order a diff/axles this week before it starts getting nice out. I have a few different routes I'm considering but I'm unsure of the limitations. So, here's the situation

Primary use of the vehicle is street driving, roll racing, potentially some 1/4 digs at some point so I'm unsure of what ratio to go with for my LSD.

Option #1 M factory diff, with either m factory axles or Driveshaft shop axles. My main concern here are the limitations of the Mfactory diff and axles, as well as the factory Drive shaft.

Option #2 Ad-e Ford 8.8 IRS conversion, obviously going to hold all of the ponies. Just costs almost twice as much.

If anyone could shed some light on the ratio I should run as well as what other higher horsepower cars are running, that would be greatly appreciated!

[gmagnus7]

Find a m3 diff,m use those beefy axles and source a CF driveshaft in custom length. Should cost you less than 3 grand total, 2.5 if your lucky.

[chris_flies]

Originally Posted by Thorfmxrdr88

I have a built e82 1M clone that's lacking lsd and strong enough axles to support the power it's making. Before winter hit (I live in the #1 snowiest city in the nation) the car put down 633whp on a mustang dyno, with about 8 more lbs of boost left. I'm looking to order a diff/axles this week before it starts getting nice out. I have a few different routes I'm considering but I'm unsure of the limitations. So, here's the situation

Primary use of the vehicle is street driving, roll racing, potentially some 1/4 digs at some point so I'm unsure of what ratio to go with for my LSD.

Option #1 M factory diff, with either m factory axles or Driveshaft shop axles. My main concern here are the limitations of the Mfactory diff and axles, as well as the factory Drive shaft.

Option #2 Ad-e Ford 8.8 IRS conversion, obviously going to hold all of the ponies. Just costs almost twice as much.

If anyone could shed some light on the ratio I should run as well as what other higher horsepower cars are running, that would be greatly appreciated!

I rebuilt a 328i auto diff with an MFactory LSD. Obviously, you wouldn't want to touch the Typ. 188 diff with that power, however, I did get to hold the MFactory unit in-hand, and it's impressive. Build quality and materials feel incredible, and their marketing screams durability and strength. I've got no input to offer on axles, as I'm not even close to pushing 300hp to the rear wheels, let alone 700+ and wouldn't even know where to begin. I've heard good things about Driveshaft Shop, and IIRC a few people around here are running the MFactory axles with good results. It also depends on what you want from the car. If you'll be drag-racing it, the Ford conversion would be the way to go for reliability. That said, people seem to do relatively fine on the street, without launching, with stock axles.

[Suprgnat]

Originally Posted by chris_flies

and their marketing screams durability and strength

I know someone on this forum that had 2 units fail. Broken ring bolts both times on a mildly modded N54. In fairness, Mfactory honored their warranty and replaced the bolts, but none of the substantial labor costs were covered.

Just sayin'.

[chris_flies]

Originally Posted by Suprgnat

I know someone on this forum that had 2 units fail. Broken ring bolts both times on a mildly modded N54. In fairness, Mfactory honored their warranty and replaced the bolts, but none of the substantial labor costs were covered.

Just sayin'.

Hmm. Are you saying marketing is wrong sometimes? No way.

I guess I'm lucky to not have too much power and torque...

[500AF]

Originally Posted by Thorfmxrdr88

I have a built e82 1M clone that's lacking lsd and strong enough axles to support the power it's making. Before winter hit (I live in the #1 snowiest city in the nation) the car put down 633whp on a mustang dyno,

kind of off topic, how did you get that kind of horsepower out of the 135?

[The Wind Breezes]

Welded diff. Max grip and no fucking around. I've been dailying one for the past 3 years.

[dtla1]

Originally Posted by Suprgnat

I know someone on this forum that had 2 units fail. Broken ring bolts both times on a mildly modded N54. In fairness, Mfactory honored their warranty and replaced the bolts, but none of the substantial labor costs were covered.

Just sayin'.

There was a time when they had a batch of bad bolts, or these failures could have been before they switched to a higher strength bolt grade.

[Suprgnat]

Originally Posted by dtla1

There was a time when they had a batch of bad bolts, or these failures could have been before they switched to a higher strength bolt grade.

It was the same diff that was "upgraded" to the new bolts under warranty, then it broke again and he replaced it with an M3 diff.

[dtla1]

Originally Posted by Suprgnat

It was the same diff that was "upgraded" to the new bolts under warranty, then it broke again and he replaced it with an M3 diff.

Very interesting, I would have loved to do the forensics of the failure mode of that.

[Suprgnat]

Originally Posted by dtla1

Very interesting, I would have loved to do the forensics of the failure mode of that.

In fairness, it was a pre-lci automatic so a 188 diff, but still...

[xQx]

Originally Posted by gmagnus7

Find a m3 diff,

I'm by no means an expert, but there are plenty of reports from e92 M3 owners having their diffs break at the track.

I'd look into that before settling on a M3 diff for such high HP.

Depending on how much street driving you do, I'd give a +1 for just welding the diff.

[Andreweatstacos]

I wanna hear more input from people with welded diffs.