I was looking around on here and other forums for answers, but couldn't find any so I figured I'd pull the trigger and start a thread, since I doubt there aren't many people wondering the same thing:
1. Is anyone running the Wilwood 12.19 front kit with Magnum 500's (stock or aftermarket)?
2. Anyone know or willing to measure the inside barrel diameter of their Magnums? And just to be clear, since they have a step, I'm talking about the actual barrel where disc calipers would be inside of.

I doubt you'll fit a 12.19" rotor with a 15" wheel. Typical rule of thumb (from personal experience) is whatever the wheel diameter is, subtract 3" for MAX rotor diameter. So a 15" wheel could hold a maximum 12" rotor. However, this rule can be violated, especially with a tall caliper or a wheel with a thick barrel (like OE wheels).

Thats what i have heard, but the wilwood kit does claim it works with some 15” wheels, and if i did my math right, requires an inner diameter of 14.12 to work.

Wilwood brakes will not work with Magnum 500’s, the center caps will not fit.

Welp theres another issue I totally forgot about, is there a way around it? And is that issue the same for any wilwood kit?

I wonder if a machine shop could mill the Wilwood's dust cap down just enough to fit the Magnum cap. I would by two extra caps though as not to void Wilwood's warranty.

I would call Wilwood to see if they have another alterative, I went with Baer brake kits.

Parts that aren't designed to work with each other rarely work with each other. If you want a disc brake kit that fits a Mopar wheel then stick with a Mopar disc brake kit. Doctor Diff has a good selection of Mopar disc brake kits and he'll be able to tell you which ones will fit which wheels.

The problem with vintage wheels is that some of them are carry overs from the drum brake era so they do not have the internal clearances to allow disc brakes to fit. In some cases this is due to large rotor diameters and in others it is the spoke clearance for caliper width. Some 500s may lack the radial clearance to allow the wheel to sit flat on the disc face because of caliper width. Some do not. Depends on when they were made. Rallyes typically do not have this problem because they are a later design with disc brake compatibility designed in, but may be diameter restricted, depending on caliper bridge height. You also have the nose of the hub issue pointed out above. This may require turning down the diameter of the whole nose section, not just the cap, to fit through the 500 hole, or opening up the wheel to allow the nose to protrude through.

This has been discussed a bit before. Find it here:
https://board.moparts.org/ubbthreads/ubbt...tml#Post2565418



Actually, 12.19 is the max diameter the nascar boys run, so it is possible and this kit in particular was designed for that application. But again, later model wheels have been made with disc compatibility in mind. My Aero wheels will fit these just fine. OEM wheels from the classic era are a big variable on what will or won't work. Even some OEM and aftermarket wheels with 11.75 discs and different calipers like Dynalites , Vipers, etc. are a wildcard. I've test fit a number of them over the years and some work, some don't.

There isn’t much meat on those center caps that can be turned down. Certainly not enough to resolve what I see in the picture.

about the only solution i see in the magnum wheel situation, would be to use a spacer of the appropriate thickness. doing that, however, would require the spacer to be a billet piece, plus the correct stud length and strength.
then, you have to take into consideration tire clearance situations. so

Just a question for Car Nut, are those original Magnum 500's? I bought the car with them, but as far as I know I have aftermarkets. Most likely the wheel vintiques.

Those are aftermarket steel magnums, Wilwood's would not fit my two piece aluminum AR ones either.