Well I just had her dyno'd.
Good!:
I gained 2 to 4 hp's up top @6200 rpm's or so.
Bad:
I lost almost 20hp and a crap-load of tq down low and didn't gain anything until 5800+ rpm's.
Po-Jay, thanks for dynoing this mod. It's good to have a quantifiable understanding of why the secondaries are there. I personally got kinda tired of people removing the butterflies and making nebulous statements like 'it pulls like mad up top now'.
These results are not surprising - think of all the hours Ford Powertrain engineers spent dialing in port sizes, runner lengths, etc. Yes, some other components like the exhaust, etc have some serious comprimises to them, but Ford didn't go through the trouble of adding a secondary intake system just because it thought it would lower engine output.
-Kurt
