A few brake questions.

[69*Goat]

I am in the process of upgrading my brake system. The car is a 69' GTO. It is a factory front disc brake car, so it is a dual M/C with two lines that go to a distribution block attached to the frame, where it splits into two lines for the front brakes, and 1 line continues out of the block to the rear drums. There is prop valve in the line between the M/C and the Dist block for the front disc, and no prop valve in the line neither before or after the Dist. block for the rear drum brakes. I am changing over to Hydro-boost, and Kore3 brakes at all 4 corners.

I am trying to get the hydro-boost system installed before it goes to the paint guy. I will be installing the Kore3 system when I get it back from the paint shop.

Here are my questions.

1) I am installing the hydro-boost system with the stock brake system in place. I have been told that the hydro-boost may blow out the rear wheel cylinders is this true?

2) I have been told 2 different things from 2 different people regarding the distribution block on the frame. Do I keep it when I switch to rear discs, or do I remove it, and install a line from the front M/C reservoir to a tee for the front discs, and then a line from the back reservoir to an adj prop valve in the line for the rear discs.

3) If I keep the distribution block, do I install a prop valve between the M/C and the dist. block for the rear discs, or between the dist. block and the rear discs.

Help would be greatly appreciated.

[Muadi]

I'm not an expert, but have done similar things.

I'm not aware of the hydro-boost being able to generate that much pressure. Hydro-boost, similar to a vacuum assisted system, provides assistance... how hard you push is up to you. I don't think your pressure could blow out a wheel cylinder, but I guess it could happen. I personally would not worry about it happening. Also remember that the factory uses hydro-boots, and they don't have issues.. you won't either.

Your distribution block sounds interesting. Usually, most factory systems from GM utilize a distribution block that is also the proportioning valve. It is also the block that has your brake light warning light switch. I have seen systems with a unit inline between the M/C and block, but I think it is more of dampener (removes the hard pulses/shocks but keeps the pressure) than a pressure reducer. Since it is inline for the front brakes, you certainly would not want to be reducing the amount of pressure... if anything, you would want to be decreasing the pressure to the rear drums.

If you are switching to rear discs, then question 1 is moot, and, you would want to get a new proportioning/distribution block that is designed to work with 4 wheel disc brakes. There are several companies that make this item... I would think Kore3 would have one as well.

I would trust Kore3 engineering/sales staff and go with their recommendations.