Opinions

RRR,
I think the boosters are the same, but the performance version has richer jetting.


Steve,
The 1405/6 are 625 cfm. If the 383 is just a mild perf engine, then it will work fine & a good choice. The factory fitted AVS was 625 cfm, & it was also used on std 440s.

Who built the engine? FT cam? Broken in correctly? What brand lifters? Cam specs?
No sir, they are different. I've seen it first hand, plus we have e member here who tore both apart and showed all the differences. They are different. Trust me.