19_Chevelle_69
06-19-2006, 09:03 PM
There are plenty of disc brake sets on e-bay, at the swap meet, on junk yard cars, but most people don't know what will fit their car. It is important to know the exact year make and model of the car the brakes came off of. Most of the parts cross over to work on a number of cars but knowing what to look for is the hard part. When ever I see a disc brake set up at the swap meet and I ask what year it came off and the standard answer is 72 Chevelle. If you look closer you can determine the exact year. The 69 to 72 GM A-bodies and the 67-69 Camaro are not the same setup. Most people know aftermarket disc brake kits fit 64-72 GM a-body and 67-69 Camaro's but that does not mean a 67 Camaro can use a 72 cutlass set and consider the car to have factory disc brakes. Lets start at the beginning.
The first year for disc brakes on GM products is 1967. All cars before this point in time had four wheel drum brakes. Disc brakes were introduced as an option from 1967-1972. Starting in the 1973 model year front disc brakes were standard and front drums were no longer available. When disc brakes were developed so was the dual master cylinder, so all 1967 and newer cars had dual masters. Disc brakes required different pressures so the master was divided into two halves to provide pressure to the front and rear separately. This also meant that if a front line blew out the car would still have pressure to the rear brakes and vise versa.
The first thing that has to be cleared up is that all 67-68 Factory disc brake cars came with dual piston calipers, if the car is a 69-72 it had single piston calipers. All after market sets come with the later 69-72 single piston calipers but this is not technically factory correct for the 67-68 cars. The single piston setup will bolt on all the 64-72 GM A-body's and 67-69 F-body's. The first issue to converting a car to disc brakes is what kind of car is it. If the car is all factory correct and that is a concern, single piston calipers on a 67 or 68 car will certainly catch the judges eye and throw up a red flag. If the car is a driver or modified car no one will care if it has the single piston or dual piston calipers. The first question we ask at inline Tube is are you looking for original appearance or are you looking for something that just bolts on and appearance may not be an issue.
The next issue is the proportioning valve since disc brakes were new in 1967 the valve was still being worked out for the next few years. The 1967-70 valves could comprise of as many as three pieces and with out all the pieces the valves would not work properly. In 1971 the valve was finally worked out and this design was used on most cars from 1971 into the 1980's. This is why it is important to know what are the correct pieces for your car. People generally refer to all blocks as proportioning valves. There are metering blocks, hold off valves, adjustable proportioning valves, residual valves and what is the right combination? Once you get past the spindle and calipers the brake lines will drive the average guy insane. With the wrong caliper the hose may not fit. With the wrong valve combination the lines may not fit properly. The fittings sizes change with the year of the valve and valves that look the same are not. Factory lines do not work with aftermarket valves and in some cases headers will hit blocks located on the frame.
Remember most of these cars are over 30 years old and parts have been changed, just because the car has disc brakes does not mean they are factory...
The first year for disc brakes on GM products is 1967. All cars before this point in time had four wheel drum brakes. Disc brakes were introduced as an option from 1967-1972. Starting in the 1973 model year front disc brakes were standard and front drums were no longer available. When disc brakes were developed so was the dual master cylinder, so all 1967 and newer cars had dual masters. Disc brakes required different pressures so the master was divided into two halves to provide pressure to the front and rear separately. This also meant that if a front line blew out the car would still have pressure to the rear brakes and vise versa.
The first thing that has to be cleared up is that all 67-68 Factory disc brake cars came with dual piston calipers, if the car is a 69-72 it had single piston calipers. All after market sets come with the later 69-72 single piston calipers but this is not technically factory correct for the 67-68 cars. The single piston setup will bolt on all the 64-72 GM A-body's and 67-69 F-body's. The first issue to converting a car to disc brakes is what kind of car is it. If the car is all factory correct and that is a concern, single piston calipers on a 67 or 68 car will certainly catch the judges eye and throw up a red flag. If the car is a driver or modified car no one will care if it has the single piston or dual piston calipers. The first question we ask at inline Tube is are you looking for original appearance or are you looking for something that just bolts on and appearance may not be an issue.
The next issue is the proportioning valve since disc brakes were new in 1967 the valve was still being worked out for the next few years. The 1967-70 valves could comprise of as many as three pieces and with out all the pieces the valves would not work properly. In 1971 the valve was finally worked out and this design was used on most cars from 1971 into the 1980's. This is why it is important to know what are the correct pieces for your car. People generally refer to all blocks as proportioning valves. There are metering blocks, hold off valves, adjustable proportioning valves, residual valves and what is the right combination? Once you get past the spindle and calipers the brake lines will drive the average guy insane. With the wrong caliper the hose may not fit. With the wrong valve combination the lines may not fit properly. The fittings sizes change with the year of the valve and valves that look the same are not. Factory lines do not work with aftermarket valves and in some cases headers will hit blocks located on the frame.
Remember most of these cars are over 30 years old and parts have been changed, just because the car has disc brakes does not mean they are factory...