7 1/4" info

[mopodge]

I just busted the spider gears in the carrier of my 7 1/4" axle. It's behind a 3000 lb. '74 Dart with a mild 318(.440 cam, 600 carb and duals)and a built tranny(2500 stall, B.W. clutches, kevlar bands, a shift kit, koleen steels). I'm thinking of getting a 3.90 gearset and a spool if i can find it. If not, i'll probably just replace the spider gears and pop in the 3.90s. First of all, will switching from 2.76 gears to 3.90s help alot? Will I feel the difference? 2nd, does anyone make a spool for the 7 1/4" differential? 3rd, will my 7 1/4" hold up behind my configuration, or break soon after the rebuild? And last, how many splines does my 7 1/4" axle have? Is it 25 or 27? Or something completely different?
Lots of questions, I know haha. I would very much appreciate everyone's help with this!

 

[Keith Mopar]

My 7 1/4 held up behind my stock 340 with a four speed in my 65 Cuda with street tires. But after saying that it sure didn't like a set of slicks, never did a single run in it with the slicks. I now have a 8 3/4 with yukon axles. :toothy7:
Going from 2:76 to 3:55's man did I feel the difference.
I tried to find a spool for you in the cataloges at the shop here and no spool,s although we don't have a great selection of brands!
If you have an auto it should hold up, but why not just step up to an 8 1/4 and make sure, you can get one cheap from a wrecker!

 

[bobscuda67]

I think 71/4 rears are a gernade with the pin pulled. I have one in my 67 340 barracuda and am going to replace it as soon as I have the funds. Build your self a nice 8/14, that will last behind a 318. The difference between a 276 gear and a 355 is night and day. You wont be able to stop smiling!