Rear end

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Rear end Rate Topic:

#1 Big Chris

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Posted 07 February 2012 - 12:31 PM

How much horsepower and torque can the v6's handle?

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#2 305 Formula

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Posted 07 February 2012 - 12:55 PM

I think the V8 and V6 rear ends are the same. As for how much power then can handle it really depends on your tranny & tires. Stock LS1s are like 300ish horse & 350ish ft-lbs I think, and with a manual transmission and redline clutch dumps they can turn a 10bolt into a wet spot on the blacktop & a pile of gears.
Automatic transmissions are alot easier on the diff.

Also street tires will put alot less strain on the diff than slicks will.

These are my guesstimates

A/T:400ish hp (Depending on stall & tires)

M/T:300ish hp on the low end (Depending on driving style & tires)

#3 96firebird

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Posted 07 February 2012 - 01:14 PM

Yes the v6 uses the same 10 bolt rear BUT there are many differences between the v6 version and the v8.

Stock 10 bolts are weak, plain and simple. They're ok on a stock engine and street tires but when you start adding power and sticky tires, it's only a matter of time before it goes. If you start making 350+ whp, and adding any type of drag tire, your best bet is to just upgrade to a 12 bolt. As 305 Formula said, manual trannys make it harder on the rear.

This post has been edited by 96firebird: 07 February 2012 - 01:16 PM

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#4 Injuneer

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Posted 07 February 2012 - 01:57 PM

The gears/housing are identical. The only difference I'm aware of is the posi rear and disc brakes were standard on the V8 models, and optional on the earlier V6 models. Obviously different engine/trans combinations came with different gear ratios. There is no set value at which the rears will start to fail. Its as simple as the higher the HP goes, the more likely it is to break. Some LT1 owners manage to break the stock rear with stock engines (275/285HP). Others have taken high HP cars into the 10's with the stock rear - it's all a matter of luck and statistics.

High Performance Pontiac magazine did a two part feature on strengthening the 10-bolt. After pouring about $2,000 in upgrades into the stocker, they declared it OK for up to 450 flywheel HP with an automatic trans, and not recommended at all with a manual trans and sticky tires. Throw in another $500 and they could have had a 12-bolt, Dana 60, or 9-inch that would be much stronger, handling 700-1,000HP.

http://www.highperfo...uild/index.html

http://www.highperfo...uild/index.html

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#5 Big Chris

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Posted 07 February 2012 - 05:56 PM

My car is rev limited to 4500 until it gets retuned and I accidentally just let it hit that and it jolted hard and now it seems to be running a little differently, I'm hoping it's not something expensive but that can't be good for the rear end.

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#6 Big Chris

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Posted 07 February 2012 - 06:28 PM

It sounds like it's coming from the alternator. I know I've been posting allot but I don't want to go broke and there's not many good mechanics around.

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#7 Big Chris

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Posted 08 February 2012 - 08:47 AM

I found the source of the noise there's a power steering fluid leak and the level is low. This is my first time doing any real work on a car but I needed a new hobby.

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#8 djfirebird93

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Posted 08 February 2012 - 07:55 PM

Hey, if you don't do it yourself, then how will you learn? Lol thats how I look at it. Where's the fluid leaking from? I had a leak at the hose, but it drained the fluid and burned up the pump. :/

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#9 Big Chris

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Posted 09 February 2012 - 10:42 AM

Thanks it's leaking out of the hose also.

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#10 FSTLS1TA

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Posted 09 February 2012 - 09:37 PM

If its one thing I know its 10 bolt rear ends. Broke 4 of them in my TA. Found a used Moser 9 inch and the car loved it.

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