Opinions vary on port size and flow etc. your 325's will be fine on your 575sci's. 360's on 548's is large runners but for all I know you may possibly have a light weight cat spinning 7,500. But again I'm only speaking from my experience. You mentioned Valako earlier. He evidently wasn't involved with the heads on the 548 project. I know him to well. What kind of boat were or are 548's for?

Getrdunn, on those promaxx 320s, what do you think they will end up at cc wise after valako welds them up?

DCB F34, the 548s were specd by Bob teague and were in the boat when I bought it. They limiters are set at 6200, talked to the builder and he pulled up the sheets, 984/986@6100. With boost the heads work damn good. I know MK always preached that in a boosted app the "the same rules apply" as NA, whatever the hell that means, I am not totally buying it. In fact if I had to do it over I think I would have saved my money and just ran my iron heads on my 575.

Jim built the motor I sold my old cat with, that is how I know him.

i built a pair of blown 548s for a cat i had,8-71s with chillers that made 950,they had old dart 320 race series heads unported and crane 651 hyd roller cam.

340 currently but haven't welded up the floors so it's difficult to say. Kind of curious to know how much material comes out on the uppers. I had an edelbrock SV drop shipped to his shop the other day and he's going to flow it tomorrow and will know more where we stand then. I told him joe he gets any larger I'm gonna be forced to do the unthinkable. I'm going to run down some parts this week to machine shop so going to stop by and see how they look. I will get some pics while there and add to the other thread.

Some 565's, those heads, I think a pair of 10-71's sitting on top, would put a smile on your face when you put the throttles to the mat in your new sleigh. Or if you up on bucks, some 5 liter whipples would do the trick too.

Jeb,
Did you ever hear how your old cat ran this year with the compression engine Jim put in it this summer?
Just curious

Ran over a 100, he had plans on running at loto because the fastest cat in that NA class ran 87.

Wow, not to shabby. Time for a tunnel ram and dual quads! Lol
Thanks

I also disagree that boost is same, my buddys 509's with 7lbs boost are around 850 hp with 525 cams and the little 295CC Edelbrock heads that come on ZZ502 crate engines, through stock Gil wet exhaust, not too shabby and very reliable.