Car is a 83 Cutlass drag car. Using stock front calipers off a 87 camaro and pbr aluminum calipers on rear. Both single piston. Master is a 1 1/8 strange unit. Problem is not enough getting to rear brakes. Wheels off the ground it will not keep the tires stopped anything above idle no matter how hard you push the pedal. Going to go to a 7/8 master and was wondering what will fit. Using a trz manual adapter
Manual brake master cyl
- Thread starter bbcolds
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Wilwood makes a 7/8" bore master cylinder. These run about $300 for the lowest priced one, but should bolt up to your adapter plate. I am unsure of the outlet sizes, but they are inverted flare.
Also, the late 80s, early 90s, front wheel drive dodge/plymouth/chrysler compact cars (Shadow/Sundance/LeBaron) came with a master cylinder that is pretty close in looks to the Strange MC. These cars came with master cylinders in 3 different bore sizes . From smallest to largest is the 21mm, 7/8", and 24mm bore. The outlet sizes for both front brakes (rear port) and rear brakes (front port) is 3/8-24. If you are using your stock brake lines, you will need adapters.
These master cylinders are now manufactured NEW in aluminum and cast iron.
The advertised size and the actual size might be different. For example, an advertised 21mm bore MAY actually be a 7/8" bore. An advertised 7/8" bore MAY actually be a a 24mm. The 24mm is usually the only one that will be aluminum and the advertised size will be the actual size. The 21mm is rare, but these usually come in cast iron, but not always. The 7/8" bore can be aluminum or cast iron, but it may be advertised as aluminum, but it still may come in cast iron. The 24mm master cylinder is usually aluminum.
The caliper casting for the g-body is the same as the third gen f-body. 1978-1981 calipers where NON low drag and used a strait bore master cylinder. 1982-1988 LOW drag and used a step bore master cylinder. A step bore master cylinder can be used for any year NON low drag and LOW drag caliper, but a strait bore master cylinder cannot be used with a LOW drag caliper as it cannot supply the volume needed for the brakes to function correctly. Good news is that any remanufactured caliper SHOULD BE NON low drag as the part numbers are all the same for all the years, but I am NOT sure about your 1987 calipers on the front.
A 1970 to 1980 H-body (Vega, Monza, etc.) came with a 7/8" bore master cylinder, but the mounting bolt spacing may not work with the adapter plate you have. These master cylinders are cast iron and have the GM outlets. Front brakes (rear port) is 1/2-20 and the rear brakes (front port) has 9/16-18.
Hope this helps.
Let me know if you have any additional questions.
Dave
Also, the late 80s, early 90s, front wheel drive dodge/plymouth/chrysler compact cars (Shadow/Sundance/LeBaron) came with a master cylinder that is pretty close in looks to the Strange MC. These cars came with master cylinders in 3 different bore sizes . From smallest to largest is the 21mm, 7/8", and 24mm bore. The outlet sizes for both front brakes (rear port) and rear brakes (front port) is 3/8-24. If you are using your stock brake lines, you will need adapters.
These master cylinders are now manufactured NEW in aluminum and cast iron.
The advertised size and the actual size might be different. For example, an advertised 21mm bore MAY actually be a 7/8" bore. An advertised 7/8" bore MAY actually be a a 24mm. The 24mm is usually the only one that will be aluminum and the advertised size will be the actual size. The 21mm is rare, but these usually come in cast iron, but not always. The 7/8" bore can be aluminum or cast iron, but it may be advertised as aluminum, but it still may come in cast iron. The 24mm master cylinder is usually aluminum.
The caliper casting for the g-body is the same as the third gen f-body. 1978-1981 calipers where NON low drag and used a strait bore master cylinder. 1982-1988 LOW drag and used a step bore master cylinder. A step bore master cylinder can be used for any year NON low drag and LOW drag caliper, but a strait bore master cylinder cannot be used with a LOW drag caliper as it cannot supply the volume needed for the brakes to function correctly. Good news is that any remanufactured caliper SHOULD BE NON low drag as the part numbers are all the same for all the years, but I am NOT sure about your 1987 calipers on the front.
A 1970 to 1980 H-body (Vega, Monza, etc.) came with a 7/8" bore master cylinder, but the mounting bolt spacing may not work with the adapter plate you have. These master cylinders are cast iron and have the GM outlets. Front brakes (rear port) is 1/2-20 and the rear brakes (front port) has 9/16-18.
Hope this helps.
Let me know if you have any additional questions.
Dave
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Helps a lot. Know about the Wilwood masters. Will look into the Chrysler ones. How do you tell if low drag calipers? Pretty sure these been changed at on point. Have another set of calipers off a 87 Monte Carlo. Took them apart and they look like any other caliper I have seen. Just one oring and dust shield.
The only difference between a LOW drag caliper and a normal, NON low drag caliper is the piston SEAL. On the LOW drag caliper, the seal has a beveled face which allows the piston to be pulled back up into the bore of the caliper more than a normal caliper and is suppose to relieve the slight drag that is usually on the rotor with a normal, NON low drag caliper. A NON low drag caliper has a squared off seal.
If you car was built between 1982 and 1988, then your calipers came from the factory with LOW drag calipers. 1978-1981 G-bodies had normal, NON low drag calipers. The caliper housing is the same and the only difference is the seal.
Any remanufactured caliper has the same part number from 1978-2003 (g-bodies, 3rd gen F-bodies, and S10s), so I have to believe that the calipers are rebuilt to normal, NON low drag standards so they can work will both a strait bore master cylinder and step bore master cylinder. A LOW drag caliper can only work with a step bore master cylinder. If you paired LOW drag calipers with a strait bore master cylinder, the strait bore master cylinder would not be able to supply the volume of fluid needed to fill up a LOW drag caliper.
If you car was built between 1982 and 1988, then your calipers came from the factory with LOW drag calipers. 1978-1981 G-bodies had normal, NON low drag calipers. The caliper housing is the same and the only difference is the seal.
Any remanufactured caliper has the same part number from 1978-2003 (g-bodies, 3rd gen F-bodies, and S10s), so I have to believe that the calipers are rebuilt to normal, NON low drag standards so they can work will both a strait bore master cylinder and step bore master cylinder. A LOW drag caliper can only work with a step bore master cylinder. If you paired LOW drag calipers with a strait bore master cylinder, the strait bore master cylinder would not be able to supply the volume of fluid needed to fill up a LOW drag caliper.
Got a seal kit for the 87 Calipers. Kit has square seal. Don't remember what was in it before(thru them out before looking at them). Proportioning valve is a 4w disc factory style valve. Took out all the guts and put a plug in the middle to separate the two halfs. Just not enough pressure going to the rear. hopefully a smaller MC will help.
Been playing with this car off and on since the last post. Went to a Chrysler 7/8 bore master cylinder, replumbed the rear lines to 3/16. Has good pedal but still don't seem to have enough psi to the rear brakes. Rear calipers are pbr single piston. Would going to a larger bore caliper work? Used the same setup except using ford Explorer single pistons rear calipers at 3280 lbs and it did fine from 140+ mph. This car is not near that fast and footbrake it. have to leave at idle or it starts either pushing the car or spins the rear tires. Any ideas???
I believe those rear calipers adjust with the parking brake mechanism, so it may be good to see if the pads are adjusted out closer to the rotor by activating the emergency brake mechanism on both calipers. You may have to cycle the emergency mechanism a few times to get the pads set.
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