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I'm looking back in retrospect, and when starting my build, I used the same master cylinders as Keith Tanner used (3/4 and 7/8), and they are way too heavy for me, requiring for me to literally stand on the pedal for it to stop. Even doing that, it's not stopping as fast as I'd like.

What's the correct size for my car? It's around 1500-1550 currently, and I'd say 175hp.

I didn't look around on the forums; I'm about to race off to school.

I would be willing to sell/trade at least the 7/8 cylinder for something smaller if I can figure out the correct size.

There's a cool PC program knocking around that lets you put in all your parameters and tells you, but you already know it's wrong and what you want. In short, you need to make your master cylinder(s) smaller. Just remember that if you want to have to push half as hard, you have to cut piston area in half, not piston diameter. This assumes that you have the margin to spare in terms of the longer pedal travel that will result. And, whatever compliance there is in the system (air bubbles, brackets bending, hoses expanding, etc that gives a sense of a spongy pedal) it's only going to make that seem worse as the smaller master cylinders have to use more of their volume as a percent to make up for it.

What ratio pedal are you using

I want to say I'm running 5.5:1 ratio at the moment. It is one of Jack's pedals modified to use dual cylinders. I think if I go from 3/4 and 7/8 to 1/2 and 3/4, I might be able to get by. It's just that I'd have a problem stopping for a kid in the road without literally lifting my butt off the seat.

I'll have to see if someone will trade on the market board.

if you are using dual master cylinders, the pedal effort will double over a single, therefore, the balance would be effected if you went to 3/4 and 1/2 so i would suggest to remain in the ball park, 3/4 and 5/8, also remember that the smaller cylinder may come on earlier.

Why not have two identical cylinder sizes with a bias bar?

Remember it's the area of the circle in the master cylinder. so a 1/2" master cylinder will make about 2.25 times the pressure as a 3/4". That might get you where you want.

If your wheel cylinders are the same size front and rear you could pull it off with just a balance bar. If they are different sizes you have to move more fluid for the larger pots. Typically you will need both dissimilar master sizes and a balance bar to get it right.