Disc brakes

[71 Runner-71Bee]

I'm slightly confussed about the brake conversions, plus I have seemed to miss every artilce written about this. I read on here to use a-body spindes and not aspen parts. Then in wanted parts I read to use Cordoba. I have 85 diplomat parts I was considering. But I want to know what the deal is. I don't want to do something unsafe. Any info would be Appreciated. Sorry For long read. Thank You In advance.

[dusterbd]

all the articles that i have read concerning this say to use the a-body pieces. i have seen the later disc spindles sat next to the a body pieces, and they are a little taller, not enough to readily notice, but enough to throw the suspension geometry WAY off. so the answer is: use the A-body parts.
it would also help to knoww the car these are going on, and what the purpose of the car is.

mike

[dave571]

The a body suspension parts(spindles) are right.

I think what's confusing you is the change up to the bigger rotors used on some cordoba's.

If you want the bigger stuff, find a model with the bigger stuff, and use the rotors, caliper brackets and calipers from it, on the a body spindles. Still use the A body(disc brake car) master cylinder and proportioning valve.

You won't noice much difference in the braking performance by using the bigger stuff, over just straight a body stuff, but some guys figure if your going to the trouble to change it, then but the big stuff on.

If you do go with the big rotor set up you have to use 15" wheels. This is an issue for some guys trying to keep the stock look.

mail me if you want 77b100@moparmusclemagazine.com

[George G. Leverette]

These are the parts you need for the conversion on the B-body:
Knuckles 73-76 A-body with Disc
Rotors 73-76 A-body, 73-75 B-body, 76-79 FMJ
Calipers 70-72 B\E bodies (pin Type) 73-78 B-body (pin type) 73-76 A-body, 76-79 2 door B-body or 79-81 R-body these are all sliders ensure the hose fittings and bleed screws are at the same end.
Brackets 70-79B-body or 70-74 E-body
Master Cylinder 15\16bore 73-76 A-body W\power disc or 73-79 B-body with standard disc 1" bore
Proportioning valve from Mopar or Wildwood.

If you choose the brackets for 11 3\4" rotors 15" wheels will be required to clear the calipers.

[goldduster]

There has been much debate about the use of the '73-up B/F/M/J body spindles. The fact is that they are a little taller, and do alter the suspension geometry a little bit. In fact, that altering of the suspension geometry doesn't really hurt the cars handling much (if at all) the problem it does have is that it could exceed the operating range of the upper ball joint. Some people have run them for years with no problems. I've never heard of anything breaking on them. I just decided I was going to use A-body spindles becase I knew they were gonna work, and I needed the UCA's anyway.

[icycleboy]

The bigger rotors can absorb more heat in the canyons. On a 4000 pound, front heavy car, I´ll take all the rotor I can get.

As to the rim clearance, I´m hoping this picture illustrates at least an option. I think 17" rims make any mopar look goo

[dbeast]

Taller spindles isn't always a bad thing. Have you seen all the recent articles on the tall spindle chevy swaps? Corrects arkaic suspension designs, helps with the roll center, and improves camber. If you can deal with the balljoint angle issue (which shouldn't be much) then a taller arm will help decrease the positive caster gain under suspension compression.

Just a thought, how much taller are they? Think I might run a set.

[goldduster]

A-body on the left, F/M/J body on the right