8.25 or 8.75 Rearend

[scott313]

Help! I have a 73 Charger that was stock with a 400/727/8.25. I am upgrading to a 440 (about 450HP). This will be a daily driver that will see some mountain road driving. It will see the strip maybe 3 - 4 time per year. I was told to yank it and put in a 8.75. The 8.25 would never handle the load and the "C" clip is dangerious. I question this since the alxe is original, almost 30years old and never had a "C" clip failure. I would be upgrading either to a Posi and apx. 3.55 ratio. Any advise would be greatly appreciated.

Thanks!

[ehostler]

the 8¾ is a superior rear end. As you are in Folsom, You should be able to find a '71 & up B-body rear with very little problems. Mather Auto Dismantlers would be my first try. They are nothing but MOPAR. After that yard, there are several more in Rancho Cordova.

The C clip in the 8¼ is a single point of failure. If you abuse the rear too much, it will snap. When it does, the axle will come right ou

[scott313]

Thanks for the info. Mather wanted $400 for a 8.75 and it was not a Posi. I will continue looking!

[ehostler]

I see them pop up on ebay every so often, as well. Recently there was on complete drum-to-drum with B-Body springs, 3.55 Sure-grip. Opening bid of $250. No one tried to get it. He ended up selling it locally for $500.

U-pull it may give you a better price on a rear, as they are flat rate cost. any rear axle assembly is one set price.

I miss all of the salvage yards around Ranch Cordova.

[dwc43]

The 8 1/4 you have wil work just fine. I have one in a charger with a 3.55:1 gear and never had any problem with it. I also have a '76 Duster with a 360 4 spd and 8 1/4 sure grip rear and it dose great.
What most people don't know was that the 8 1/4 was a replacement for the 8 3/4. It's just as strong and a little lighter and they used it as the good piece since the big block cars were dieing out when they developed this rear.
The 8 3/4 is just easier to change gears in that's all. The next step up would be the Dana 60 which is over kill in anything but a drag car.
So just put that sure grip and gear in that 8 1/4 and go burn some rubber and kill some chebbys.

[deadhorse66]

Originally posted by ehostler
I see them pop up on ebay every so often, as well. Recently there was on complete drum-to-drum with B-Body springs, 3.55 Sure-grip. Opening bid of $250. No one tried to get it. He ended up selling it locally for $500.

U-pull it may give you a better price on a rear, as they are flat rate cost. any rear axle assembly is one set price.

I miss all of the salvage yards around Ranch Cordova.

Dammit, that's high! I just went to the local u-pick to get a price on a rear center section for my Monaco (wanting a sure-grip). He said $90 for a drum to drum assy., and cheaper if I wanted to pull it myself! Guess the economy isn't quite as thriving out in redneck land as it is in Cally! Must suck for you guys.

[dwc43]

Got to remember the cost of living increase. They make more than we do so they can get charged more too. Funny how that works. Poor fellow can never get ahead anywhere can he ???

[deadhorse66]

Is it all po' folk? I thought it was just me! LOL

[ehostler]

By the time you are done paying to upgrade an 8¼ to sure grip with good gears, you may have well bought an 8¾. Also, you need to remember that the later RB engines weren't putting out as much power as the earlier ones were. There was no real need for the 8¾. Given the choice, I'd take the 8¾ over the 8¼ any

[chrisnben]

I too have a 8-1/4 rear in my newly aquired '76 Duster 360 w/ a 4.10 sure grip already installed. The ultimate question still stands: Will this thing hold up to 500HP in a small block w/ slicks and good axles (Moser)? Or should the 8-3/4 be swapped?

[scott313]

Thanks for all the advise. I am going with the 8.75. I found an E-Body 8.75 with a posi for $50. It even has 3" brakes. I have always been told the 8.75 is the stronger rear end and I just don't like the "C" clip. All I have to do is move the spring pads. I just have to drive 4 hours to pick it up. Again THANKS!!!!!!!!!!!!

[ehostler]

The E-body rear on the '73 B-body is a great setup. The E-body rear is 1.3" more narrow, so you can fit a fatter tire in the well, without offset rims.

[dwc43]

Originally posted by chrisnben
I too have a 8-1/4 rear in my newly aquired '76 Duster 360 w/ a 4.10 sure grip already installed. The ultimate question still stands: Will this thing hold up to 500HP in a small block w/ slicks and good axles (Moser)? Or should the 8-3/4 be swapped?

It will hold up. Like I said before this was the replacement axle for the 8 3/4 when it was dropped from service. I've never seen a mopar c clip problem. If your worried just put a spot weld on it like the chebby dirt trackers do. Ask Sanborn he'll tell you most all chebbys run c clip rears. When they break they break the axle just behind the bearing.
I've run the 1/4 axle on dirt before with over 400 but not quite 500 and it never broke. Sliddin one side ways puts more torture on the axle than a good wheel up lauch. I used to run them on a few street cars years ago 'cause you get 'em every where from police cars with suregripps some with 3.23's up to 3.55's. Good rear. Not worth chasin down the 3/4 if you have a 1/4 unless you just have your heart set on one. 3/4 dose make gear changes quicker though.

[chrisnben]

thanks for the input DWC43, very helpful. I've always run E-bodies w/ 8-3/4's- never had the smaller rear before. Think I will pick up the stronger axles anyway and weld the clip. Ever get to Detroit- give me a shout. chrisnben@peoplepc.com. Take care, Ben.

[The Dartman]

The 8 1/4 rears are not too strong. I broke the sure grip in a profesionaly setup 8 1/4 with a Richmond gear in only a 14 second car. The C clip did fail and the axles attempted to come out of the housing at least a foot. The SG unit came apart, and pieces go into the ring gear and toasted the R and P. This was under normal driving conditions back when I used to drive my Dart Sport year round. If the car had been under power, or racing, who knows where this axle might have ended up.

I said before that if you do it, do it right the first time. Would I replace the 8 1/4 if it had sure grip and good gear? Nope. Would I put more than the cost of gear lube into an existing one? Nope. It all depends if you get the opportunity to pick up good a 8 3/4 rearend (especially an A body 8 3/4). Just don't sink a bunch of money into something that's not exactly what you want or need.

Dartman