when searching the pic and pulls, what other cars can you take parts from to make a 67-72 a body big bolt pattern? and what do you take off? say a diplomat, aspen, volare or m body cars?
big bolt pattern
- Thread starter rbkt65
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Nothing off those cars you mentioned. You need a body a axles for the rear and early b body spindles for the front or late a body spindles.
thanks.
Professor Fate
Push the button, Max...
Au contraire. The F/M/J spindles are a perfectly viable option to convert A bodies with. You still need the big ball joint upper control arms from a late A body in order to use them.
Disk Brake Conversion Info
Spindle Comparison
Disk Brake Conversion Info
Spindle Comparison
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Exactly!
On an FMJ car you can pull the spindles and everything out from there and use that as a BBP disk conversion. In fact I’ve done exactly that on my Duster, although I’ve upgraded brakes again since then.
The later B/R body brakes can also be used with the 73+ spindles, and you can get 11.75” disks from those.
All of that’s covered in the articles @Professor Fate posted.
You can also use C body and (some) truck 8 3/4 axles and have them cut down and re-splined for A-body 8 3/4 use. Although DoctorDiff axles work better for that and aren’t so much more expensive when you consider shipping axles to Moser or something like that.
Rear drums/backing plates etc can come off of any BBP RWD car, some of that stuff carried over until ‘89 IIRC.
Ah yes, Ehrenberg’s completely unsupported claim.
It’s bullshit.
Bill Reilly actually checked the geometry and published it. You can see for yourself in the article he wrote, @Professor Fate posted the version that was on Big Block Dart, or you can read it here.
Swapping Disc-Brake Spindles - Mopar Muscle Magazine
In short, Ehrenberg was completely wrong. The FMJ spindles work great, and arguably better for some set ups. Like mine. I run them on my Duster and my Challenger. Ball joint “overangling” isn’t a real problem with that swap.
Dave999
Well-Known Member
with a taller stub you alter the roll centre of the car its like using longer balljoiints (ask a 57 chevy dude)
the effect on handling is much like lowering the car without lowering the car.
go too far though and the upper a arm bump stop doens't work anymore the upper A sits higher, and it would then, with wheels off the ground, allow too much suspenion droop... just don't do dukes of hazzard jumps... all will be ok.
the effect on handling is much like lowering the car without lowering the car.
go too far though and the upper a arm bump stop doens't work anymore the upper A sits higher, and it would then, with wheels off the ground, allow too much suspenion droop... just don't do dukes of hazzard jumps... all will be ok.
all very enlightening so far. on rear axle, i have several choices. so picking 1 of them that will cost me the least will be of consideration as long as the quality is there.
Yeah, I understand the theory. But if you look at extended ball joints for racing they come in 1/2”, 1”, even 1.5”. The difference between an A-body and FMJ spindle is less than 3/8”.
And here’s the real deal, the changes in geometry were all plotted out in that article. There’s no need to speculate about what might or might not happen, you can literally see the tiny difference in geometry that occurs from using the FMJ spindles, and if you want to apply theory then you can argue why that change is actually positive, depending on your set up.
The factory geometry was for bias ply tires, which use totally different alignment specs and benefit from different geometry than radials do. So just saying that maintaining the factory geometry is best is misinformed.
Professor Fate
Push the button, Max...
Another way the FMJ spindle height is helpful:
When building a big block or hemi A body (even some smallblocks with tall manifolds) it is common practice to use K frame spacers (like the factory did on the '68 SS darts and Barracudas) to keep things tucked under the hood, or at a desired level.
The added height of the FMJ spindles helps keep geometry from getting too out of whack.
F body 8 1/4s also fall into the same width range.
Both are becoming tough to find, though.
Early five bolt Dakotas and Jeep XJs may also have 8 1/4s in a similar width range. A tape measure is your friend here.
A much more available (and probably cheaper, too) option, as distasteful as it may be to some, is the 8.8 rear from a Ford Explorer (which can also get you factory disc brakes, limited slip, and gears in the mid to high 3s):
8.8 swap
When building a big block or hemi A body (even some smallblocks with tall manifolds) it is common practice to use K frame spacers (like the factory did on the '68 SS darts and Barracudas) to keep things tucked under the hood, or at a desired level.
The added height of the FMJ spindles helps keep geometry from getting too out of whack.
For the rear, an 8 3/4 from a '70 and earlier B body is only about an inch wider per side, easily worked around with correct offset wheels, and sometimes not even needing that- depending on your body style.
F body 8 1/4s also fall into the same width range.
Both are becoming tough to find, though.
Early five bolt Dakotas and Jeep XJs may also have 8 1/4s in a similar width range. A tape measure is your friend here.
A much more available (and probably cheaper, too) option, as distasteful as it may be to some, is the 8.8 rear from a Ford Explorer (which can also get you factory disc brakes, limited slip, and gears in the mid to high 3s):
8.8 swap
my buddy uses 8.8 from explorers. he buys a rear end, then another short axle. has a friend of his cut/weld the axle tube.
i have 3 8.75 housings but 2 are c and 1 is a truck. we own a narrowing jig. so not a problem there. have the axles also. guy close to here cuts and resplines axles, not sure of cost at this time. don't own a center section.
find an a body housing and axles but as high as they are, probably not cost effective.
probable solution- i have 7 truck dana 60's, a narrowing jig, 3 ls diffs, dr diff ends and perches,. can have axxles resplined ot buy dr diff axles. any of the above would be the solution but at what dollar amount for me to spend. overbuild and never need another rear end(dana 60).
you members are the best. lots to think about.
i have 3 8.75 housings but 2 are c and 1 is a truck. we own a narrowing jig. so not a problem there. have the axles also. guy close to here cuts and resplines axles, not sure of cost at this time. don't own a center section.
find an a body housing and axles but as high as they are, probably not cost effective.
probable solution- i have 7 truck dana 60's, a narrowing jig, 3 ls diffs, dr diff ends and perches,. can have axxles resplined ot buy dr diff axles. any of the above would be the solution but at what dollar amount for me to spend. overbuild and never need another rear end(dana 60).
you members are the best. lots to think about.
Jarlaxle
Well-Known Member
Jeep Cherokees used 8.25" axles to 2001. (Only Cherokees WITHOUT ABS used it-with ABS, they used a Dana 35.) The vast majority had 3.55 gears-4.0/5-speed used 3.07 gears. A handful with the Up-Country suspension or tow package used 3.73s. I think 4-cylinder/5-speed used 4.11 gears. There was little rhyme or reason except for ABS-the only way to know is to look underneath-though probably 90+% of Cherokee Limiteds had ABS. No tach or no tint probably means no ABS.
The XJ donut spare will also fit your A-body.
The XJ donut spare will also fit your A-body.
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