What are those 12 pt bolts from the block into the head? Extra head bolts?

Yes.

And they suck to do lol

What block is that ?? bushed lifter bores, who did the machining

That pic I put up was an entrant to the Engine Masters competition some years back.

Most, if not all, aftermarket blocks have the provision for that extra head stud...many aftermarket cylinder heads do also.

Just up your alley. Typically a rectangular port intake will be used and the floor of it's runners epoxied up, and then matched to the heads.

There are only a few companies that get/use that cylinder head....you won't see it in the Brodix catalog but it is available.

I have the flow #'s here at work some where. If I find them, I'll put them up.

Edit in, found them:

Runners average 301cc


Lift / Intake / Exhaust CFM at 28"H20
.200" 170 126
.300" 250 177
.400" 307 212
.500 347 246
.600" 373 267
.700 384 279
.800 388 288

we'll be releasing our new "Oval" port soon...stay tuned for details!!

Ok so anyone interested in purchasing AK Racing/Promaxx can refer to my classified add in the engines/parts section!! thank you everyone!!

Count me in on a set of the custom fit and ready to go Promaxx 320 heads.

Thank you Steve, you won't be disappointed!!