So is the stock rear-end strong enough for, say around 400 hp/tq? I am going to be running drag radials all the time on mine and eventually upgrade to
3:73's as well. I have heard arguments on both sides. Any opinions and suggestions are welcome. Thanks!

 

Its a crap shoot...I've been running 420rwhp thru my 10 bolt for 10 years on BFG DRs with only wearing out a Auburn...I run GM 3.42s, stock axles, and just recently installed a Summit cover from Spohn. I do change the fluid and additive religiously every year. 60's in the 1.60s-1.70s. Some run slicks thru them with no problems, some explode on street tires..I would be more confident with an A4 than an M6 as sticks are general harder on the launches. Do a search and you'll probably find pages and pages on this subject...
--Alan

 

Thats pretty much what the guy that is helping me with my engine said. What brand fluid and additive do you use?

 

I used to use Mobile 1 synthetic or Red line with the GM additive, but Auburn recommends the old dino lube, so I use Valvoline 75w90 with the GM additive..I might drive the car 5000 miles a year, but they are hard miles, so I do it anyway...Thats the main reason for the rear end girdle...I just wanted a drain plug...I would say that you'd be OK if you have an A4 with those power figures (assuming rwhp) and Drag Radials...If you are going to upgrade the gears I would strongly suggest a good limited slip like the Eaton or a PRO series Auburn, new bearings, and look into a bearing stud kit ( I don't have one, but I hear good things), look into the solid pinion spacer (again, don't have, but...), and a good TA or Summit cover...

The bottom line is that you can throw the whole aftermarket at the rear, but it won't make the 7.5" ring gear bigger or stronger than it is...My philosophy with the rear has been that if your tires are spinning a little, then your rear will be ok...Dead hook it and your days will be numbered. In my case the DRs spin just enough not to break anything....yet...
--Alan

 

I have the BFG's as well so I'm sure they'll give enough. Also have you had any computer issues from your stall converter? I talked to a place that said even with a tune that they didn't think one over 3000 would work on a 94-95 lt1. Doesn't sound right to me. Thanks!

 

I have had no problems with my 3600 at all. The car was tuned by LPE for the converter.