Disc conversion nightmare

[Chad-1stGen]

The master cylinder you are using comes in a number of kits and in fact is the one I'm using on my car. Factory vettes in that year range used 1" for the manual m/c and 1 1/8 for power. Personally I'm using the MANUAL m/c with a power booster (booster had correct rod adapter). Witht he car off brake effort is excessive though I'm using the power brake hole on the pedal.



Speaking of which make sure you are using the right hole in your pedal. I believe it's upper for manual, lower for power but maybe someone else can confirm since I'm going on memory atm.

As already mentioned you need to ditch that proportioning valve. There are relatively cheap disc/disc 5 port valve that retain the brake waring light otherwise you can use an inline adjustable on the rears and plumb the fronts direct off of a T or Y block.

I didn't change the front to rear line and currently the 1/4" line is working.

Oh one other thing. I don't think you want to use the residual pressure valve. They don't typically come in kits that use that M/C so unless for some reason the calipers you are using require it (not familiar with them) I'd ditch it.