KH brake upgrade

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Mikes270dart

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I have a 1967 Valiant with 9" drum brakes. Want to upgrade to front disk. Will this kit work, it is from a 1971 duster. Thaks
 
I did this conversion on my convertible with 9" drums. The prop valve is a bit of an issue. Right now you will have a junction block/safety switch where the lines go from the master cylinder. The K-H factory setup had a separate adjustable prop valve downstream of this on the rear brake hard line. You can't buy this part, and it will be hard to find used. 73-up disc brake cars had a prop valve (of sorts) built into the junction block/safety switch (also called a combo switch). You can buy this from Classic Industries and others. The problem is that, being non-adjustable, it may still put too much pressure into the rear brakes. That was my experience (weight distribution and tires may be a factor). I resolved it by adding a Summit adjustable prop valve into the rear line. Some people put this between the MC and the junction block -- this is convenient for plumbing purposes, but I think it is a better idea to follow the factory practice and put it in the rear line coming out of the junction block. You can do this without cutting and flaring if you just buy a short hard brake line from the auto parts store (maybe 14-18 inches) and bend it into a loop. The output from the junction block goes into the input of the prop valve using this piece, then the output of the prop valve goes onto the existing rear line. This locates the prop valve directly beside the junction block -- you will find that the ones from Classic have a bracket on the side that is perfect for bolting them together. Tidy, mostly out of sight, and reachable for adjustment. If you have headers however this may not be practical. One more thing -- I bought new hard lines for the short ones that run between the MC and the junction block, because otherwise you may need an adapter for the end fittings -- the disc MC may have different sized outputs.
 
Sorta disagree as the original style hold off valve is still readily available as well all the lines needed. It is not adjustable though.

If I did not want to keep my 4” bolt pattern wheels I would have gone to the later units. IMO the KH setup is not that great and would be happier with some good old drums. These KH front discs have been a disappointed from the day I bought the car in 1984. On my resto in 2014 “everything” and I mean “everything” has been replaced with new components and lines and at least 3 different masters. I could stop my B body with drums much faster! I had really believed that after every piece was replaced and fetered this would be great, but still have the disspointment of 4 piston calipers that work less than some simple drums.

Do you have the correct bolts for the calipers?
 
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By the way my opinion is based on an original 69 PDB 383 car. The best my pedal ever felt caused release lockup on the front and destroyed the calipers and discs 30 years ago trying to maximize the push length. Still wonder how I was able to stop this thing @105 on the 1/8th. I have tried later metallic and now run the original style organic pads and still unhappy. Maybe this car is cursed but my drum brake cars never felt this way.
 
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