The first time I met HD, I was having trouble with my Paxton-blown '65 1/2 Mustang. I managed to get hands on one of the VS-59 blowers that Paxton built for the race '57 T-birds. The area in the main casting that would be machined for the boost limiter was simply a blank spot and on my 'K' engine with a few 'improvements' I could get more than 15 pounds of boost.
The thing is, you have to run a connection from the fuel pump to the carb enclosure or you lose fuel pressure as the boost goes up and lean things out, which is a bit tough on your pistons. And when you let off the loud pedal, you get a momentary bit of high pressure on your gas you don't need. This slams the floats in the carb, and the brass bends where the float's are soldered to the float arms.
I used to go out Telegraph Rd and pick on 396 Chevy IIs. But I'd end up parked under a street light with the hood up and the carburetor apart to straighten it out. The supposed answer was to solder braces made from thin brazing rod to help stiffen the floats, but I was still having to replace them every couple of weeks.
I was told to call Harold. He built me a carb specifically for the application, with the first nitrophyl floats I'd ever seen.
Problem solved.
KS
