Alright im looking to replace my rear at about 105k, i will have a much more powerful motor in about a year or two tops. i dont want to redo my rear to hold the hp. what are some good suggestions for a rebuild..gears?...ratech bearing and shim kit??... id like to hear what some of you guys have done.. THANKS

 

12 bolt... 9"... that's the only way to be sure.

Otherwise, you can beef it up but it would be a waste of money... a cover, good fluid, lower gear ratio (higher number values) are weaker by nature... That's all I know.

 

If your car is going to be an everyday car then I would recommend going with a 12 bolt. If you car will be more of a drag car then I recommend going with a 9-in.

 

Agree with IDOXLR8 (but wish people would use their names, which are easier to spell).

One thing more, I really doubt those covers do much good. They sure do look purty though, that's why I have one on my 12-bolt.

Rich Krause

 

Just curious IDOXLR8, but why do you say that a 12 bolt is better suited for everyday driving as opposed to a 9"? I thought the 9" would hold up well in all circumstances? (drag racing, road racing, daily driving) Or am i wrong? Just wanted to get another opinion on this. Thanks.

 

Maybe he's referring to the weight difference? I think the 9" is lighter than the 12 bolt???

 

I read recently in one of the mags that the 9" Ford was slightly stronger and easier to work on but the 12 bolt had about 1-2% less drive train power loss when compared to the 9". He may feel that the power loss is a more acceptable trade-off at the track for reliablity reasons.

 

He also may be refferring to the difference in gear noise that comes from the two diffentials that can get quite annoying. The nine inch is a lot louder than the 12 bolt. The whining coming from the 9 inch can get to be quite annoying and there is nothing to be done to quiet this. So unless you don't mind the noise on a constant basis the 12 bolt is a better choice for overall peace.

 

What makes you think a 12 bolt is quieter? Everyone I know with a 12 bolt complains about gear noise, including myself. I can't imagine a 9 inch being much worse, if at all. In fact the guy that did my last ring/pinion in my 12 bolt said that 9 inch rears stay quieter after racing them. A 12 bolt may be quiet when everything is brand new, but one good 60 foot and then you get loud gear whine. If I didn't have an M6, I'd stick with a 10 bolt as long as possible.

 

Well lets see are you an auto or stick?How much track time do you plan on doing?How much money will you have to spend?

 

9" you'll need to delete your !ABS system, not that big of a deal when you consider how crappy the factory Bosch and Delphi system is.

9" create much more heat than a 12 bolt so I would recommend a rear end cooler if you go on long trips, other than that, I beleive the 9" is a bit lighter... does anybody know if its the Moser/Strange third member that the torque arm mounts to or the housing?

The way I see it, if its the third member that the torque arm mounts to, you can get a Currie aluminium housing for about $1150 with brackets installed and axles and misc. peices and you have yourself one light rear end.

 

You can run ABS on a 9 inch if you aren't running 4 channel ABS. Don't ask me how to do it, but it can be done and I know someone with a 96 Z28 who's done it.

 

Yeah but you have to drill into the housing, mount an exciter ring from something like a 80's Ford truck on the differential and wire in a GM sensor... PITA!

Take out the whole ABS system, will work fine on a street car... hell the Viper's don't have em.

 

How much power can the factory axle/rear end take

 

Less than stock