I have a 87 IROC with a 383 with s/r intake , tf heads ,slp cam and a dry 100 shot of n2o . The stock 9 bolt is shot ,the posi carrier is no longer a posi it is a 1 wheel peel . What whould be the best way to go . Fix the 9 bolt with new carrier and change gear ratio to 3:73 ,4:10 for a good chunk of change . Or go with a 12 bolt or nine inch for fairly twice the cost of the rebuild . I want a dependable rear end . Buy the way I have 3:27 ratio in the car now which is a series 3 carrier . Thanks for the help .

 

i'd go with a 12 bolt

 

if you got the money get the 12 bolt. the 9 bolt is hella strong though. ive seen people with big blocks/massive power running the 9 bolt rear....http://www.ringpinion.com and ive heard TONS of good things about that site on the 9 bolt kits with the yukon gears. im thinking of trying them myself

 

If your gonna shell out the $$$ for a 12 bolt...just get a ford 9in. Same price...stronger....easier to change gears....

 

9" uses more HP to spin than a 12 bolt it's not really any easier to change gears on one than the other. to me it's much harder on a 9" becasue everything seems backwards and i have to think more about which way to go. it is easier to swap carriers on a 9".

 

Auto or stick car? If its an auto car, then I would say just rebuild the 9 bolt, unless you are talking hella power. You can rebuilt it more than a few times for the price of a 9" or 12 bolt, and the auto will be easier on the rear end than at stick will, b/c it helps preload the gears. If its a stick car then go w/ a 12 bolt. Eats up less hp than a 9" does.

 

not nessicarily. There's a magazine that just did a comparison of a 9 inch, 12 bolt and a dana rearend. thre were no ET or mph changes. Someone on this board was talking about it recently. It's one of those things that you hear about and somehow it gets converted from myth to fact without any real proof. There's alot of things like that in automobiles.

To answer the question on the post, by far a 9 inch would be your best bet, but asbefore mentioned, a 9 bolt is hella strong. Just depends on if you are dead hooking and how much money you have to spend. You might also want to look into the 8.8 conversion for our cars. I am trying to get more info on that, but people aren't talking a lot about it.

Jason

 

The Ford 9" uses more power because of where the pinion is set on the ring gear. Both the 9" and the 12bolt are hypoid gear sets(as as most vehicles). But the 9" pinion is father away from the pitch line of the ring gear. This equals more friction/heat which is waisted HP....

Now how much I cant tell you, it might not be a whole bunch, but its not a "rumor" or a "wifes tale" its just physics...

 

Chevy High Performance tech aticle.....

http://www.chevyhiperformance.com/techarticles/0304_nine/

 

sorry

http://www.chevyhiperformance.com/te...les/0304_nine/