disc brake conversion

[SkidmarkSS]

I know this subject has been beat to death but,my 87MonteSS in my sig has the stock master cylinder,booster,and prop.valve.Please list eveything i need to upgrade because i did a rear disc brake conversion with FBody/LS1 brakes,and do i keep my stock booster?Thanks,Chris

 

[355_79bu]

Here is what you will need:

A disc/disc master. I used one off a 79' vette. It should work for your car.

Get rid of the stock prop. (combo) valve. It has several disc/drum features which are not compatible with a disc/disc setup. Instead, use an adjustable prop. valve in the rear brake circuit, and run the front brakes straight off the master. You need no residual valve whatsoever because your master is mounted higher than the calipers.

For the booster, the factory g body dual diaphragm booster is ideal. The single diaphragm will work, but is no ideal for disc/disc.

Feel free to PM me if you have any other questions.

 

[LS6 Tommy]

You shouldn't run an adjustable prop valve instead of a combo valve unless you're running separate front & rear race style master cylinders that are equipped with a balance bar setup. On factory based or street systems you use it with the proper combo valve to tune rear bias when you have excessive rear caliper pressure.

You can use a disc/disc combo valve that bolts into the stock location, (Master Power Brakes #VL3359A: http://www.mpbrakes.com/products/product-detail.cfm?product_id=613) then add an adjustable prop valve later if you still have too much rear brake bias. It may not be cheaper, but technically it's the right thing to do because the combo valve continually balances the front/rear brake bias at all pedal pressures to help eliminate rear lock up just like factory disc/disc setups.

I know some feel that there's no need to do this and many state they have no problems with doing away with the combo valve. I'm just relaying my experiences and posting the way brake system engineers tell me they would do it.

Tommy