Race valve is a H type valve (as opposed to J, F or C varient).
I have one at home. Very aggressive on initial spool up. Boost is at least a couple of psi higher. Doesn't seem to hold boost as long as the F type, though, which was OE on mine (older ones came with the C type). Limp mode was a regular occurence on the H valve, so I went back to the F. The F feels much smoother IMO. Some cars will work fine with the H type, some won't. No rhyme or reason to it I'm afraid.