beefing up the rear end
08-16-2007, 12:50 AM
#21
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I broke the stock 3.42's when I was completely stock. Ripped a few pinion teeth out, and a few ring gear teeth. No bearing damage or anything.
I replaced those with the ever-so-whiny Richmond 3.73s. Those lasted about 35k miles until it spit a couple pinion teeth. Once again, no bearing damage. However, upon disassembly, the end of the carrier actually came off (was still in tact in the housing). Just the small endpiece that hold the carrier bearing. This may have been a contributing factor to that rear breaking.
I did not know that different ratios of Motives were made in Italy. I'll keep that in mind, but 3.90 was the perfect gear for my DD.
I replaced those with the ever-so-whiny Richmond 3.73s. Those lasted about 35k miles until it spit a couple pinion teeth. Once again, no bearing damage. However, upon disassembly, the end of the carrier actually came off (was still in tact in the housing). Just the small endpiece that hold the carrier bearing. This may have been a contributing factor to that rear breaking.
I did not know that different ratios of Motives were made in Italy. I'll keep that in mind, but 3.90 was the perfect gear for my DD.
08-16-2007, 01:15 AM
#22
Is there a company that does the 8.8 ford mustang conversion? Out of all the options I think that one is towards the top. They are cheap, and mustang guys beat the **** out of them and they hold up. It's almost a 9inch but not quite. I don't know how the TCS or ABS would work though. I have a 00' with a 6 speed, the guy that had it before me had drag radials on it. It's just a matter of time before it blows.
08-16-2007, 06:34 PM
#24
Originally Posted by 85Iroc
I say this a lot .......... IMO, don't put any money into the 7.5" rear if you EVER plan to put sticky tires on it. Doesn't matter how much money you put into it, it WILL break. I know a guy that put $1000 into his 7.5" & it broke the very first launch at the track.
If you have someone who can weld, the 8.5" 10-bolt is a very good option. I put a stock one in my 3rd gen with only a gear change & mini-spool & everything else stock held up to many 6.0s to 6.20s passes off a transbrake. I used ladder bars but curry & I believe moser offer tq arm brackets that you can use now so it would be a pretty easy swap, besides keeping ABS.
If you have someone who can weld, the 8.5" 10-bolt is a very good option. I put a stock one in my 3rd gen with only a gear change & mini-spool & everything else stock held up to many 6.0s to 6.20s passes off a transbrake. I used ladder bars but curry & I believe moser offer tq arm brackets that you can use now so it would be a pretty easy swap, besides keeping ABS.
08-16-2007, 07:24 PM
#26
Originally Posted by NC98Z
Chuck I've been torn between a 8.5 10 bolt or a 8.8 ford rearend with the series3 ABS sensor. Do the 8.5s have the ABS series 3 hole on top of the diff or are the setup for the abs sensers on the end of the axles? Can you give us a heads up on what years, what models of chevys that the 8.5 came stock on? I've got a damn good axle/driveshhaft place in town and if all I got to do is buy/cut reaxle some pictures of your setup would be greatly appreciated.
As far as the rear itself goes, I'd say most of the stock ones are actually too short for a 4th gen....... well, too short to keep the stock rear wheel offsets. The one I put in my car was out of a 76 camaro & was roughly 1" total length narrower than the stock 3rd gen rear I think. I can't remember exactly. I don't know how much longer the 4th gen rear is than the 3rd gen but it would work with different offset wheels. Now, the 8.5s also came in g-bodys but they have the upper control arm mounts on them but you could probably still weld the proper perches, etc. onto it. They would likely be longer than one out of a 2nd gen camaro, but I haven't measured them in a long time. I feel like I'm rambling & not making any sense, bear with me.
It would be best/cheapest if you could find one that you could make work without narrowing or lengthening it. That way you could keep the stock axles, they're pretty tough. No c-clip elims would be necessary since the disk brakes would hold the axle in, in case of failure. Any axle failure would most likely occur on launch. The brakes will work with slight modifying of the backing plate. I did have to have the stock axles put on a lathe because the stud end of them was to large diameter to fit inside the disk brake rotor.
Pics of my setup really wouldn't do much good since I have ladder bars. I did have the stock shock/spring perches on it when I first put it in but have since changed to coilovers.
Hope this helps a little. Let me know if I made sense or not. I have the crud today & am not thinking too clearly.
08-16-2007, 09:10 PM
#27
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In regards to the comments on sticky tires, i have a stock A4 1998 T/A with 3.23 gears and i recently put Eagle F1's on my car and i proceeded to launch with absolutely 0 spin or even a squeal my rear end has never broken or made any noises, knock on wood, and my car currently has about 82-83K on the odometer. so if you have an A4 i'd run it till it breaks but i've never held back any.
08-17-2007, 09:31 AM
#30
Originally Posted by The Spot
In regards to the comments on sticky tires, i have a stock A4 1998 T/A with 3.23 gears and i recently put Eagle F1's on my car and i proceeded to launch with absolutely 0 spin or even a squeal my rear end has never broken or made any noises, knock on wood, and my car currently has about 82-83K on the odometer. so if you have an A4 i'd run it till it breaks but i've never held back any.
08-21-2007, 08:16 AM
#33
I guess everyone pretty much knows that if you have the money the best option is a 9". That isn't breaking news. Not everyone has over $2000 to drop on a 9".
If you could make a 8.5" work for very little money then you'd be doing well. A completely stock 8.5 will take a LOT of abuse & can be found very cheap. The trick is finding one the right width & how to make the ABS work, unless you just wanna delete it.
If you could make a 8.5" work for very little money then you'd be doing well. A completely stock 8.5 will take a LOT of abuse & can be found very cheap. The trick is finding one the right width & how to make the ABS work, unless you just wanna delete it.
08-21-2007, 05:14 PM
#34
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gear setup
Originally Posted by Trust
This topic doesn't really apply to A4 cars, especially stock geared cars (I'm in the same boat as you). A4 guys rarely have problems with the rear as the tranny takes most of the load, we can run 10's on the stock 10 bolt. M6 rear ends take alot more abuse as there is no buffer like our A4's act like. Aslo 90% of the 10 bolt rears that break on M6 cars have aftermarket gears, I know several people that have ran low low 11's dumping the clutch on the stock rear, but as soon as gears go in, boom.
09-04-2007, 11:32 PM
#35
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I also agree with the others, don't mod the 10 bolt. Get a 9" or 12 bolt.
But I have a question for everyone as well... I heard the cheapest thing to do is go down to a salvage or something and get a 12 bolt rear end from a GM car or truck. Any thoughts on this?
But I have a question for everyone as well... I heard the cheapest thing to do is go down to a salvage or something and get a 12 bolt rear end from a GM car or truck. Any thoughts on this?
09-18-2007, 05:08 PM
#36
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Originally Posted by jmdale1984
Sucks that GM put such a **** rear end in such an awesome car... I mean, a 7.5" 10 Bolt in an LS1 Fbody, is kinda like a really hot chick with a stinky puss. You really wanna get on it, but then again, you really don't.
Hope you don't mind but I've got to use that quote on the local board
