Am I Crazy For This Idea?

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thedartsport

thedartsport

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Recently picked up a 1973 Duster with a slant with manual small bolt drum brakes. I currently know where a 1976 Dodge Aspen is with a 318, 904, power disc brakes, and big bolt pattern. The initial thought was: Can all of this be swapped to my Duster? And that's what I'm coming to you guys with. Is it possible? I'm pretty sure these cars have the transverse torsion bars, but would that even be an issue? Lots of ideas but unsure if the execution is worth the trouble. I've swapped BBP V8 suspensions to a slant with SBP before, but it was from another A body. If not the whole thing then possibly the spindles and rear axle, but again compatibility is my issue. Any suggestions? Or am I crazy?
 
Anything is possible, limiting factors are only your wallet and skillset.
 
The rear end is not a bolt in deal, I think it has the ISO spring perches, and I think it is also a little wider, but that can all be changed.I think the drum to drum width difference is quite a bit, which with skinny donuts I think it can still work.
The A body perches are at 43" compared to about 44.5 on the Fs.
I think the Fs are about 3 inches wider,drum to drum.
The F body has a B-body brakes on it;which are the same as the 73 up A-body V8 stuff, so as long as you take everything between the control arms and including the upper control arm (leave the shock), I think you can make it work. I think.
Your 73 slanty K will not accept the V8 without custom Schumacher mounts.
Your rear crossmember will work.
The driveshaft may have to be custom.
I think I got it right.
 
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I have an F-Body 727 and Rear in my Cuda. It was a simple matter of moving the perches for the rear, but the 727 bolted right in.
 
The A body upper control arm only fits A body cars.
There were TWO A body upper control arm designs as far as I have seen. ALL models through 1972 used a small upper ball joint no matter the brake style, 9", 10" drums or the 11" discs. In 1973, things got busy. Slant six cars with 9" drums still used the same small upper ball joint. ALL cars with 10" front drums or 11" discs used the larger upper ball joint that was also used in every F/M/J/R and B body.
Here is the short story: IF you have 9" drums, you'd either need the big ball joint upper control arms OR call Dr Diff. He sells a spacer kit for $50 that allows the use of the small ball joint with the disc knuckless/spindles. You will still need 73-76 A body disc LOWER ball joints. The Aspen/Volare used a different lower ball joint and steering arm design.
The Aspen/Volare axle is a good swap if the spring perches are moved to fit the A body position. The axle is wider as stated but that is a good thing. Dusters/Demons and Dart Sports with stock rear axles have that narrow looking, sunken in tire look. I have a similar width B body axle on this car with a 5.5inch rallye wheel.

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thedartsport said:
Of course, but my question is what can and cannot be a direct fit?[/QUOTE/
The short answer is NONE of it is a direct fit...............I owned two FMJ bodied cars, didn't care for the frt. suspension or working around the K-frame. I'd grab the drivetrain, &
frt. calipers/knuckles, & forget trying to cadapt the rest.
Click to expand...
 
So it's looking like my best bet is robbing the rear axle and drive train then converting the front with A body parts. It's not an R/T or anything, but would it come with an 8.25?
 
You must not have read me right. The Aspen brakes will work. Go back and read my last post. Read it a few times. I've done this many times.
If you ask for help, pay attention to those that take the time to respond. Nobody here is paid to help you.
 
As Kern Dog said, grab the front spindles, calipers and rotors off the car as well. Using the big ball joint upper control arms (if you have to buy them I'd just go ahead and buy qa1 tubular control arms) and 73+ lower ball joints, the spindles will bolt right into place. One benefit that the FMJ brakes have over the A-body brakes is the calipers have a bigger bore/piston in them therefore offer a little better braking performance. I have all the front brake stuff from a 79 aspen on my 72 Duster and they work great!
 
Your '73 may have the larger upper ball joints already. My '74 did even with drum brakes (the front drums were 10" and the rear were 9").
 
Small upper ball joint 73's are very unusual. Very, very unusual.
Ball joint adapters from DrDiff solve the problem if you have them.
Lower ball joint is the same for all 73-76 A's, disc or drum.
F's are bent bar cars. You wont be able to use any suspension parts on an A body. Control arms off the F will not work.
Spindles, rotors, calipers, caliper brackets, prop valve, dust shields, soft lines, etc. grab em all.
If your going to get new/reman calipers get them for an 80 F body. Better positioning of bleeder/inlet.
Rear could be a 7.25 or an 8.25. 8,.25 is a 3" axle tube, 7.25 is 2.5". They were pretty much all 10"x2-1/2" brakes. HD had finned drums.
Use the schumacher conversion mounts. They are very nice pieces. I have a set in my Demon and the fit is excellent.
 
Forget what the parts books show. The 9" front drum brakes were still put on some Slant six cars as late as 1976 year model! I owned a stripped down, rubber floor mat 76 Dart 2 door equipped this way. I think the only options it had was an automatic trans and an AM radio. No sway bar. No electric windshield washer pump. 19" radiator with NO overflow jug.
 
Kern Dog said:
Forget what the parts books show. The 9" front drum brakes were still put on some Slant six cars as late as 1976 year model! I owned a stripped down, rubber floor mat 76 Dart 2 door equipped this way. I think the only options it had was an automatic trans and an AM radio. No sway bar. No electric windshield washer pump. 19" radiator with NO overflow jug.
Click to expand...
Yup. And I've got a 75 Duster with 9" drums and SBP all around.
 
Re the front brakes, there is a good article by Rick Ehrenberg that has been linked many times. It discusses using FMJ spindles (Aspen) in an A-body. Many have done so. Worst-case, if your UCA's are the small ball joint and you can't find later UCA's or buy the stud adapter cone mentioned, you can buy new tubular UCA's which allow better camber & caster adjustment. Not terribly expensive for the added bling.

Another idea on the rear is to adapt a Ford 8.8" rear-end (Explorer). It requires shortening one side (cutting and welding). You can find posts. Gives a stronger rear-end w/ disk brakes.
 
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