Easy Your factory fresh air cleaner will mate properly to the hood(Ok, close enough). :laugh: Actually Jim W did some dyno comparisons, all very close but the ported performer did make the most power, and if I'm not mistaken, the performer out of the box (no port matching) made the least power. Much ado about nothing.
Couldn't help myself, mainly because I asked the same question a couple years ago and got a gaggle of opinions very few matching the last. Performers are cheap, plentiful and when properly port matched pretty impressive in the performance department. B4b's used to be harder to get, but I've heard are being produced again. Out of the box they're said to be just a bit better in the flow department. If your really looking to get somewhere with your intake your gonna have it port matched so why spend the extra? Unless the nostalga thing is something your after and that would make the B4b the natural choice. Really wanna make some power? Get an SPX.
The B4B's runners were more equal, which is why the carb was slightly off from factory spot. The Performer kept the carb's position, but it does make some of the runners shorter than others. But above it correct, a ported and flow matched Performer outperformed a B4B. I don't belileve the difference was huge if I remember right. I think there wasn't more than a 10 HP difference overall. But for the best times, every little bit helps.
Phil Your old Buick really runs good. The truck weighs 2820 with me in it. 455 stage 1 1970 Thanks for the info on the b4b. RonJ
