7-1/4 question

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prostreeter9

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Hey Guys:

I have some questions about the 7-1/4 rear ends. First do they make axles in BBP for them? Second what all would i need to convert them?

Jon
 
There are BBP axle 7 1/4 rears, but the end of the axle housing tubes are different, then the SBP rear. The axles and axle bearings are also different. The SBP bearing retainers have 4 studs with nuts to hold the axle in the housing, while the BBP 7 1/4 rears had 5 studs. So you cannot swap axles between the housings. I just redrill the SBP axle and drum for BBP.

PS: Would you like a BBP 7 1/4 rear with 5.13 gears and SG? :)
I have one.
 
Hey Charlie
Thanks for the info, sounds like I have some issues to work out. Might be interest in your's but don't need 5.13 rears. I'm building a 64 valiant mild street car.

Jon
 
I might have parts to put together a BBP 7 1/4 with 3.91 gears.
Problem is shipping charges are a bear.
64 Valiant streeter. Slant six, or V-8?
 
It's a 318, running 40 over KB piston, 256 Comp cam and 714 heads that have 1.88, 1.6 valves. The bowls were opened up and smoothed out for better flow. I have TTI headers and a performer intake. just a mild street build.

Jon
 
It's a 318, running 40 over KB piston, 256 Comp cam and 714 heads that have 1.88, 1.6 valves. The bowls were opened up and smoothed out for better flow. I have TTI headers and a performer intake. just a mild street build.

Jon
My recommendation. Drill the axle flanges and drums for BBP. If you wind up spending money on the rear, don't use the 7 1/4 , up grade to something that is stronger, and has better part availability.
The 7 1/4s are stronger then most people give them credit for, especially with SG, ( I ran a 7 1/4 with slicks and nitrous running low 13's without breaking) but parts are getting harder to find, at reasonable prices.
 
The 7-1/4" i just got has bbp. 75 dart 4 door. Was it a dart? Think so. Thought they was a c clip axle.
 
The 7-1/4" i just got has bbp. 75 dart 4 door. Was it a dart? Think so. Thought they was a c clip axle.
7 1/4 is not "C" clip. 75 Dart 7 1/4 rear will bolt right in. Might have to change the brake flex line, not sure. Might also have to change the speedo gear in the trans, if gear ratio is different. That might take some doing, as those gears are hard to get. They are 60-65 only.
 
Ok, im confused. Will be tearing it down this weekend. Guess i get to learn something new,but not really. Learn something old. Did bearings in a few older mopars 30 years ago. Will get my stuff together soon enough. Guess all i have been dealing with lately were c clip rears. Assume a rear cover was naturally a c clip style.
 
Hey Charlie:
Do you just have a machine shop drill them for you?

If I go to something else wouldn't it involve a lot of change?
Jon
 
I'm getting confused. If you have another complete BBP rear, why not just swap the complete rear assy? I drill my own axles. I used to be a tool and die maker, and made a drill jig, years ago.
Some upgrade rear swaps are involved, and some are easy. Some are costly and some aren't.
A fairly easy swap, (if you can find a used rear in your area) is a 8 inch Ford, from a early V-8 Mustang/Comet/etc. It is almost a bolt in, and gives you a "dropout" chunk, BBP, strength, and parts availability. Almost as strong as a 8 3/4, for much less money. Must be from V-8 for 5 lugs, 6cyl had 4 lugs. Has same width, spring perch width. Can hook to the driveshaft with a "Hybrid" U-joint, but I like the idea of having the Ford driveshaft "ears" for the u-joint, put on the mopar driveshaft. That way it is easier to replace the u-joint if required, in the future.
 
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OOPPS, Not confused anymore. Did not notice it was tooljunkie that mentioned about just getting a BBP 7 1/4, and not prostreeter9
 
Charlie S,Im curious about this drill jig,have you shared this in the forum before?
 
Charlie S,Im curious about this drill jig,have you shared this in the forum before?
No, it is a plate with drill bushings in it. I just clamp it on the axle, and put it in a drill press, then drill. Haven't tried it, but I think it might be able to use it on front hubs, also.
 
Hey Charlie:

I wish I did have a BBP rear end. So i have another question, can the BBP drums be used once a get these axles re-drilled?
 
I'm not sure. I would have to look. If the dia and width of the BBP drums is the same as the SPB drums, then probably.
 
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