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Old 04-16-2015, 05:19 PM   #26
Kaptain Kadian
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Re: Proportionate valve or distribution valve

The rear line fitting is too small, the front fitting is too big.

The master cylinder is a cpp with according to the tech support has a 1" bore. It is from a drum/drum upgrade.

How can I tell what size lines and fittings I have?

Thanks guys
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Old 04-16-2015, 05:53 PM   #27
leftybass209
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Re: Proportionate valve or distribution valve

There are different sized lines between manual and power brake master cylinders, and drum/drum, disc/drum master cylinders I believe.
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Old 04-16-2015, 05:54 PM   #28
Davidf
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Re: Proportionate valve or distribution valve

Most of the time people just rebuild the brake lines and use the correct flare nut for whatever size is needed. Yes, you need a disk/drum specific master cylinder as the calipers need much more volume of fluid than the wheel cylinders. IIRC, the proportioning valve fitting to the rear brakes (only one) was larger than the two for the front (disk brakes). I built all my lines, so that was not an issue for me. You might consider reducers.
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Old 04-16-2015, 10:23 PM   #29
Kaptain Kadian
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Re: Proportionate valve or distribution valve

Well, after 10 emails and 6 phone calls, I finally got a consistent answer. They finally agreed that my 1" bore would make my brakes really touchy and they recommend changing it it a 1 1/8" bore master cylinder and proportion valve. They have the combination for $139. I also figured out I have a 7/16 front line fitting and a 9/16 fitting for the rear lines. I don't really want to change the brake lines right now, so they said they have an adapter kit to fit my lines to the valve for $10. This is probably what I am going to do. Any other suggestions?
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