8 1/4 rear end strength

-
1

1ToughDuster

Well-Known Member
Joined
Feb 19, 2009
Messages
71
Reaction score
8
Location
atlanta, ga
I have a question for those of you who run an 8 1/4 rear end. How strong is the 8 1/4 rear when it comes to hot street/ occassional strip use? I know that 8 3/4's are what most people prefer but since the 8 1/4 is already under my duster, I'm thinking that it may be best and cheaper to just beef up the 8 1/4 and call it a day.

I've read where posi trac units make the 8 1/4 stronger than an open axle rear end and that c-clip eliminator kits can also make the 8 1/4 more durable. Horsepower will be about 380-400hp on the motor/ 505-525 on the nitrous.

Is anyone out there using this rear end behind heavy horsepower engines or for drag strip applications?
 
I tore my 8 1/4 to pieces with just over 300hp and a strong shift kit hit second gear down the strip and all went to hell lol. It did last me over a year before it went and they are plentiful to get parts off of.
 
Sounds like your 8-1/4 was on the tired side. I've put more power to them on a daily bassis. I'd have no issue with the above build except the No2 part. That is pushing it. I'd look for a 8-3/4 with the No2.
 
Anything over 400hp with a 8 1/4 you,ll be taking your chances/life at the track.Trust me,I had the axel and wheel pass me.Lucky to not ruin my 1/4 panel.Go 8 3/4/Dana.
Picture 010.jpg

Picture 010.jpg
 
I've read that the 81/4 was used in some performance applications but "performance" back in those days probably meant "mild" performance. I'm going to go ahead and build the 8 3/4 and have piece of mind that I'm safe. Thanks for the pics pettybludart and everyone's information.
 
You know, I thought about beefing up the 8 1/4 but since I have the housing, complete 11" brakes, and 3.55 sg chunk, I may as well go ahead and buy a $215 set of a-body axles from moser and put it all together.

I'll need to shorten the housing a bit and move my spring perches some but overall, I think that it's cheaper than buying a $239 - $400 dollar 8 1/4 posi unit, c-clip eliminators, and cap support cover for the 8 1/4 rear that's in it now.
 
I'm sure that there are but I'd hate to have my axles looking like the guy's above. I'd rather spend little more money to build an 8 3/4 now rather than spend the money to build the 8 1/4 and break it and have to spend more money to build a 8 3/4 later.
 
If you weren't running nitrous I'd say you'd be fine but nitrous is a drivetrain killer. For that reason you better at least do all the upgrades for the 8-1/4 or it'll probably crap on you.
 
LOL, yea, with the nitrous, I'd go bigger. The 8-1/4 is tuff enuff for most app's naturally sucking down just plain ol'air and fuel,but that N02 is a whompin power adder and will increase torque right close to the like of added HP it's set up for.

Press a button and a 100 - 150 lbs of torque instantly....that could be bad, 400 ft lbs to 500+, yikes!
 
You must log in or register to reply here.
-

Back
Top