rather than buy a 12, im gonna build my 7.5 up some. i'd like to know what you guys that have already done this are running.

my plans are to get some good axles (moser/strange), bigger posi (auburn/eaton/etc), and a set of richmond gears. i'll prolly get a girdle as well.


thanks, jon

 

Just my opinion, but there is no substitute for 12 bolt or 9" Ford. And...I understand Richmonds are noisey.

In conclusion, you will probably hear a whine just before the explosion.

 

a 7.5 can be built to take more than what i even plan on dishing out. i agree 12 bolts and 9in's are nice, but they're just like alot of things people think they need. bigger is better right? wrong. why spend money where its not needed. perhaps if i was building a low 10sec or faster car i would consider one. then again, i'd probably wait until i NEEDED one.

BTW, you're talking to someone who has owned two vehicles with richmond gears and ridden in countless others. so save your opinions for your bandwagon buddies.



jon

 

The limiting factor of the 10-bolt is the physical gear size. They can only be loaded so much. It's almost ALWAYS the gears or carrier that break, and there's not a whole lot to be done about that other than launch style and available traction.

A tightly meshed gear setup and a solid pinion spacer are the two biggest assets you can have. The girdle wouldn't hurt but I wouldn't invest in things like new axles... the carrier and gears will typically fail long before the axles can be overloaded.

If you plan on hard launches with good traction start saving up for a real rearend... especially with six-speeds!

btw, Richmonds are noisy in these cars

 

How bout you ki$$ my....

 

I've seen may go in the 11's and some in the 10's. I'm going 11's with mine and don't have one bit of whine. I have motive gears. Welded tubes to make them a little more beef. I build my own rears and have done it for some others on the board as well. It can be done very easy.

 

I have mine built up as far as you would want to go with the stock rear end:

Motive 4.11 gears, posi, solid pinion spacer, girdle and stud kit plus all new bearings. I didn't weld the axle tubes because I have a spohn torque arm so theres no stress on the axle tubes.

Even with all this you know what I'm doing? Saving up for a 12-bolt. I launch easy on drag radials by slipping the clutch from 2500rpm. If I dumped the clutch from 5000rpm, I'd be going home on the back of a flat-bed.

GM should never have put a 7.5" 10-bolt behind a V8 especially in a muscle car.

 

BAD97SS and I put mine together. Weld the tubes to the housing, get a good carrier and good gears. A solid space instead of a crush colar, Timken brgs, Studs for the caps, and a girdle.... thats just about all you can do. You can go with aftermarket axles too but as already stated, the carrier or gears will break well before you run into axle problems. Set the backlash tight for strength. They will be noisey but will be stronger. Use a good synthetic oil and additive and you have a pretty stout 7.5 10 bolt. Mine broke on me once last year... and the carrier was the only thing that really was bad. I had well over 400 runs on it and it wasnt built like the one in there now. Many hard launches on the new one and no problems yet. times in sig...

 

Sounds almost exactly like what I've done with my rearend with the exception of welding the tubes. I was thinking about it but since the torque arm absorbs all rotational torque, welding the tubes didn't seem like an effective trick for these suspensions. I also switched to RedLine's "shockproof" gear oil. Either way you are more an exception than a rule. Keep in mind that most people here are not going to setup their own rearends and we all know how good some shops are

 

i did mine and have only broken one ring gear which is prolly related to the cold air and no warm up
get thesolid spacer and studs and good motive gears

 

Projectz28:

the only reason yours is lasting cause u have an auto

 

Its not usually the hp that breaks the 7.5......its traction....high rpm launch with drag radials and good hook = broke 7.5. Even if its biult your just buying alittle more time and a few more hard launches. Your gonna throw alot of money at it that could go towards a 12 bolt IMO. In the long run youll wish you didnt spend the $ tryn to stengthen the 7.5.....dont ask how I know

 

Hey John...good to see you still post!

My 10-bolt has been through hell and back, and it's still kicking!

 

In my opinion, the secret to making a 10-bolt live is to keep it behind an automatic. I broke mine twice on street tires, the first time the carrier broke, the second the pinion was missing a couple of teeth. This is behind a 6-speed. I have a friend in Las Vegas with an '84 Camaro, all drag car, 383, TH350, etc. He has a picture of it on his desk pulling the front wheels off the ground. He runs 10.5X's. This is on the original 10-bolt, It has 4:10 gears and that is it. He will get the boot if they find out it still has C-clips. 10-bolts had only 26 spline axles in those years. I don't know what stall he has or what his 60-foot times are, but he does power brake it to launch, so his driveline is loaded and there is no "shock" load. Unless I was going to leave the engine stock, I wouldn't put a dime into a 10-bolt again if it were behind a manual trans. With all the $$ I put in mine, I could have paid for half of my 9-inch.

 

I am running Motive Gears & Eaton posi with new Axles. It feel strong but soon I will be welding the Axle tubes. I hope it will hold up for a good while.