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70 RR drum to disc swap

troy0924

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Hey guys. Just picked up a nice 70 Roadrunner but it has drum brakes on the front. I have a 72 charger parts car that has disc on the front. Can I swap them?
 
There is a wonderful, very extensive and in depth thread somewhere about that. I wish I could remember where I saw it recently. I wasn't even interested in it but the thread was so good I had to read the whole thing.
 
Yep, that is the same set-up that was optional on the 1970 RoadRunner. Single piston caliper with round slider pins. I have this exact conversion on my 1964 Polara. They actually came off a 1970 RR about 40 years ago. The spindles are interchangeable side for side. I hung my calipers at the rear, so they would not interfere with my sway bar. Get the master cylinder and brake block with proportioning valve as well. I noodled this out before any of the Mopar magazines were putting out articles aout disc brake conversions. I had to move the brake line bracket ahead of the A-arm from behind it.

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In a word - yup. :)
Wish I had a donor car laying around nearby - the only two currently available disc conversions that
utilize the original spindles out there new are from Wilwood and Leer - and both are $$$.
Scarebird has been out of their magic brackets for what seems like forever now...
 
Don't throw away the 11" drum brakes, someone will want them.
 
Yep, that is the same set-up that was optional on the 1970 RoadRunner. Single piston caliper with round slider pins. I have this exact conversion on my 1964 Polara. They actually came off a 1970 RR about 40 years ago. The spindles are interchangeable side for side. I hung my calipers at the rear, so they would not interfere with my sway bar. Get the master cylinder and brake block with proportioning valve as well. I noodled this out before any of the Mopar magazines were putting out articles aout disc brake conversions. I had to move the brake line bracket ahead of the A-arm from behind it.

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Great! That is the answer I was hoping for!. Thank you very much.

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Yep, because they stop the car just as good as factory discs! :)
If that were true, don't you think all the newer cars and trucks would still be using drums and shoes?
Truth is, discs do stop better and cool better.
 
If that were true, don't you think all the newer cars and trucks would still be using drums and shoes?
Truth is, discs do stop better and cool better.

Truth is, discs are cheaper to produce and assemble on the production line. Newer discs sure... they work better. 1970 tech, basically zero stopping difference.

There are very few here that are actually driving their cars where fading would be an issue, vs the cost and many times nightmare of doing a drum to disc swap.
 
Truth is, discs are cheaper to produce and assemble on the production line. Newer discs sure... they work better. 1970 tech, basically zero stopping difference.

There are very few here that are actually driving their cars where fading would be an issue, vs the cost and many times nightmare of doing a drum to disc swap.
You are entitled to your opinion like the rest of us of course. I agree that not all upgrades are for the better however, I believe I am in the majority that think the discs are an improvement. Most of us believe replacing a single pot master with a dual bowl is much safer also but you can always find someone who knows better. Human nature I suspect.
 
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Back in the mid-'80's, I was using my 1964 Polara as an everyday summer car, driving it to work, etc. At the time, I was also on our rural VFD. One day, I was at work and my pager went off, signalling a fire. It turned out to be a structure fire, needing as many firefighters as possible. I left work to attend, and in the course of leaving the city and arriving at the site, stopping at stop signs, slowing down for corners, etc., I found that I had outdriven my 10" drum brakes. I finally stopped well down the road from where I intended to. Scared the crap out of me. I started looking for disc brake parts that weekend.
 
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