[undy]

I run a 5/8" front brake master cylinder, but I don't think M/C size is your problem. It's an improperly adjusted balance bar. Before you start juggling master cylinder sizes adjust the balance bar for more rear brake bias. Tilton has a real good set of instructions on their web site. All this is assuming that both systems have been been bled properly and your rear circuit is not air-bound.

I'm getting ready to do a Wilwood 12.19" 4 piston conversion on my fronts. I'm currently running Exploder 11" rear rotors/calipers and my fronts are GM metric calipers on Mustang II spindles/11" rotors. The 5/8" M/C gave me the front brake stopping power I needed. I may need to go with a larger front M/C with the Wilwoods.

Dave