Is this worth attempting or not....12 bolt rear for my LT1
08-22-2009, 02:51 PM
#1
On The Tree
Thread Starter
Join Date: Nov 2007
Posts: 111
Likes: 0
Received 0 Likes
on
0 Posts
Is this worth attempting or not....12 bolt rear for my LT1 I've got the chance to pick up a 78' 12 bolt rear for a lil of nothing out of a wrecked truck "hit in front". How benifical will it be for me to get it and work on getting it ready for my 96' Z28. I haven't heard much about this kind of project. Or am I better off just saving the money to purchase a ready bolt in unit?
08-22-2009, 03:08 PM
#2
Staging Lane
iTrader: (3)
Join Date: Jul 2008
Location: Las Vegas, NV
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
you will either need another 10 bolt, or commit to making the 12 work (and plan on being out of a car for probly a couple weeks) i say this cuz you need to cut the brackets off the 10 bolt(brake brackets, spring perches, lca brackets, panhard bracket, shock mounts etc...) and reweld them onto the 12 bolt. also, the axle tubes will need to be shortened, and the hardest part of all will be welding up a torque arm bracket (incase youve never done it, welding mild steel to cast iron is NOT easy.) then youll need the proper length axles, and a new driveshaft. its quite an involved project, and unless you have some fabricating experience, can be quite dangerous. imo, and trust me ive thought long and hard about doing it myself, it would be wise to just save up and buy a bolt on piece.
08-22-2009, 03:12 PM
#3
TECH Apprentice
iTrader: (5)
Join Date: Dec 2007
Location: Southern Colorado Front Range
Posts: 347
Likes: 0
Received 0 Likes
on
0 Posts
Unless you're a good fabber and welder, you're going to find it more of a pain in the *** then it's worth. Then you have your ABS, TCS, torque arm, and disc brake system to deal with. After just getting the unit ready to mount, then you have to worry about what you have for a carrier and axles. If you need to buy and install a good posi carrier and pinion/ring set, you might as well have saved and gotten yourself a Strange S60 for all the effort. At least the aftermarket prefabbed units carry warranties and customer support if you do have issues. Just my 2 cents though.
Boils down to how bad you have to have that particular 12 bolt in your car as to whether it would be worth it.
Boils down to how bad you have to have that particular 12 bolt in your car as to whether it would be worth it.
08-22-2009, 03:38 PM
#4
On The Tree
Thread Starter
Join Date: Nov 2007
Posts: 111
Likes: 0
Received 0 Likes
on
0 Posts
Ok... thats what I thought. Well what options do i have to prep. the stock rear...kind of beef it up a bit until I get a newer 12 bolt or 9 inch? I've heard both sides of it but want more on if it worth attempting to build the stock unit to hold about... no more the 400 to the wheels.
08-22-2009, 03:56 PM
#5
Staging Lane
iTrader: (3)
Join Date: Jul 2008
Location: Las Vegas, NV
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
with an m6, i wouldnt bother building it to hold up. the ring gear is simply too small. you could weld the axle tubes, 27 spline axles, stud girdle, triangulated rod ends, etc... but at the end of the day, it CAN still break. 10 bolts are hit or miss, but when you start playing with sticky tires and an m6, its days are numbered regardless. if you want your stock 10 bolt to last, just dont launch it
08-22-2009, 04:20 PM
#6
TECH Apprentice
iTrader: (5)
Join Date: Dec 2007
Location: Southern Colorado Front Range
Posts: 347
Likes: 0
Received 0 Likes
on
0 Posts
I'm pushing 410 right now. laux06 is right, and I agree completely with him. The only time I actually have issue with it is when the tires actually hook. Last time my 10 bolt shelled it was the driver side carrier bearing. Best you can do is put the money you would use to build up the 10 bolt toward the 12 bolt or S60 (even better) and stay out of it until you have the replacement in the garage ready to go. Then I would sell the 10bolt, you have babied to keep intact, to offset the replacement cost.
Trending Topics
08-22-2009, 05:08 PM
#9
TECH Enthusiast
I broke my rear end with the mods you see. I have beat the crap out of it. The day it snapped is the day it hooked while going sideways. Not while doing my usual hard launches. Picked up a junkyard 10 bolt for now, but will be going 9 inch when I save up enough.
08-22-2009, 06:42 PM
#10
TECH Apprentice
iTrader: (5)
Join Date: Dec 2007
Location: Southern Colorado Front Range
Posts: 347
Likes: 0
Received 0 Likes
on
0 Posts
Availability, price, and replacement/upgrade parts: A built 9 inch. They're rugged enough, but there is just something about putting a Ford rear end under my Camaro that makes me cringe. eBay has some heavily modded 9 inch cases in the neighborhood of $800-$900. But you will need to install your own carrier assembly, axles and such.
I have also seen some really nice Mosers going for less than $2k complete here on LS1tech as well.
You can also realistically build up your 10 bolt to handle 400rwhp. But for the $1600 or so investment, not many people stay satisfied with 400rwhp once they are there. When your rear tires actually hook is when things start coming apart... and 400 rwhp ain't any good unless it does. If that is what you decide though, I have used the Eaton and Powertrax units and like them. Be sure to use good USA made bearings and a quality ring and pinion set, Strange or Moser street/strip axles, a quality support/girdle cover and it should be able to hang. But like everyone else has said, the tiny *** gear set is the Achilles heel.
08-22-2009, 10:25 PM
#11
I wouldn't waste any money beefing up the stock rear with a m6 car because eventually it WILL break. I brought an S60 for my 94 m6 so I won't ever have to worry about breaking it.
