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I have a '67 Dart I am going to put disk on it.

I've read a lot about police brakes from the early 1970s these brakes had 11.75 rotors (frequently referred to as 12" rotors), and were fairly thick. These brakes have been considered the ultimate junk yard swap, but due to declining availability are becoming more scarce.

Second, I've seen brake kits offered by many other companies that claim 11" rotors, my question is, are these rotors the 11.75" or are they actually only 11.00 inches and therefore inferior to police rotors available from the factory?

Third, I just noticed that Riley has 12.19 brake kits now on sale. They seem like a good deal at $700.00 and if they offer better performance than the 11.75 cop car rotors that would be great. Here are my concerns and quesions not just for the Riley kit but all kits in general:

1) Are your kits designed for daily street use?
2) This car will be used for high performance street driving 99% of the time and will be stopping a full bodied, full weight, 67 A-Body with a big block, will this kit offer fade resistance and durability to handle living on the street?
3) Are the rotors thick enough to withstand repeated hot stops without warping? (I have a cabin in the mountains and would like to put some rather continuous stress on the brakes that would generate a lot of heat and I don't want vibration from warped calipers)
4) The car is a play car that will be driven less than 5000 miles a year, do the brakes have seals and enough corrosion resistance to sit for a couple of months and not leak? What I am worried about here are racing calipers that are designed for high performance use, but require constant attention and maintance.

If it is not obvious, what I am looking for is a braking system that is at least comparable to a facotry police set up in performance, has the durability of the factory set up, and is a true bolt on (I don't mind replacing spindles).

Thanks

Regards

Winston

Anyone who can answer
 

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To start off with the so called police brake's were not just on police cars. they came on 70's B Body's like Cordoba's and Fury's. They are 11.75" and the 11" ones are 10.87".

There has been talk on other racing sites about guys putting huge brakes with all the bells and whistles on lite cars and not being able to keep enough heat in the to work fully.

It's not just the rotor size, but what pads you use with them too. I have read a few tests that with just swapping pads has made up to a 20 ft difference in stopping for 60 to 0.

The 11.75 rotors are vented and are 1" thick and can be bought at most auto stores still. There is even a guy on Ebay that is selling them that have been cross drilled.

The disadvantage to the stock stuff is the weight of them and the calipers. Most of the after market stuff is much lighter. The calipers have one big piston (but still work good) where the most after markets are 4 or 6 smaller pistons that give a better, more even grip.

For your car 11.75" rotors with 11 x 2 1/2" drums in the rear with good pads / shoes should be fine. This is what was put on 4000# plus cars form the factory. 600 to 700 less is a big difference on a braking system.
 

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i used the 12 in. kit on my dart when i instaled the alterkation. i am very happy with them. my car is manual brakes, and it stops great. i just got my car on the road a couple weeks ago, so i can't tell you how well they hold up ( heres hoping ). when you use the 12 in. kit you have too use 16 in. or larger wheels. just somthing to keep in mind.
 
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