Here are just a few data points. Also, a reminder that this thing had STOCK heads. I think the heads were the restriction, therefore the manifolds did not make drastic changes; except for the really bad ones, the different intakes just wiggled the numbers around by 5-10 hp or shifted them to the low rpm (dual plane) or high rpm (single plane). I'm pretty certain there will be more difference between the intakes once some better heads are on the engine. I find that out at the end of the month.
Street Dominator
3,000: 381, 217
4,000: 449, 342
6,000: 395, 452
Torker
3,000: 395, 225
4,000: 455, 356
6,000: 397, 454
Perf RPM
3,000: 408, 233
4,000: 457, 348
6,000: 392, 448
DP4B
3,000: 419, 239
4,000: 454, 346
6,000: 387, 442
Performer
3,000: 418, 238
4,000: 452, 344
6,000: 382, 436
Six Pack
3,000: 413, 236
4,000: 459, 350
6,000: 391, 447