Geterdunn - you also have to remember, which all of us need to remember, that alot of the compression and a/f 'safe' ratios and 'safe timing' settings where set before modern combustion chambers, wide band's, and etc.

Plus most, not all, boats being set up to run as much cold water as possible thru the engine provides a lot cooler head temperatures than those running arm/hot water back thru the block.

Jim just returned my call. I'm gonna have a set drop shipped and will keep you posted on results. I think flow will fall in line with worked over EQ's, Profilers, darts, afr's etc with the 320 runners. My biggest concern is valve seats which is ductile iron I'm pretty sure as well as all the right holes in the right places and angles.

I will be on the maintenance program big time first 50 hrs especially paying close attention to the seats getting hammered up in the heads.

So what heads are you going with?

Promaxx 320's starboard side and EQ's port side. Will help weight distribution when running solo... Jim wants to play with the promaxx and see what he can do. Evidently he's pretty impressed with the casting but not much or any seat time with them but wanting to give them a shot.

How about 332's.

Jim ordered today. Done thinking about it. To much other chit going on in my life right now. I think about engine builds etc about like a kid looking forward to his first remote control car or mini bike. Well now maybe iPads or Xbox.

Anyway it's done. Now it's up to Jim to work his magic.

They'll end up about there if I had to guess. Hah

So once somebody gets a look at the promax 320's, what would be the likely difference on a 454, 8.5 comp, 731 cam and 525sc blower?

And being alum, if the comp stays at 8.5 with 5 psi boost, would one be able to use lower octane fuel??

Jim V just finished 2 sets of eq320s for my 525sc rebuild. Here is the flow numbers with just a bowl port.
.2 148 151
.3 223 201
.4 295 240
.5 340 273
.6 375 289
.65 387 292
.7 391 295

Chamber was 122c.
Pretty decent numbers.

Awesome!