Master cylinder swap now having problems brakes sticking.

Any advise please!

I have a 1971 Demon braket racer that has had the front drum brakes replaced with a 1973 disc barake setup. Their is also a line lock set up installed. The car ran and braked fine with the original mastercylinder. I have since than replaced the small block with a big block and I am using fenderwell headers. Some other racing friends told me about swapping out the old style master cylinder to a new style to help on heating problems from the headers as seen in pictures below. I notice that when I went to go put the car on the trailer that it was kind of dragging. Then when I went to take it off the trailer it wouldn't even roll back. infact when I put in reverse to help it off the trailer I had to give it a little more gas than usual. When the tires were on the ramps they sucked the ramps right back to the stowed postion and then the car fell off the trailer. Talked about shocked I have never had this happen before but than again I never had any problems rolling off the trailer. Thankfully no damage was done.
So my question to you all is this, do I have to change out the porportioning valve from the 1973 disc brake setup I have now to one that is from the new master cylider era say around 1985? Or do I need to look at something else maybe?
Thanks
AJ "TAZZ" Schneider
Thanks again to FABO for these forums

Original and new master cylinders



New one installed