Or stick a blower on them!

Gellner used to make some big power out of 468's back in the day.

yea... my buddy built a 468 14:1 with Brodix heads, full sheet metal 62 impala ran 10.8@ 125 mph... thats a HEAVY car...

I built a 468 for a 26 Baja for a friend of mind in St.Clair Michigan years ago. Engine was 8.75:1 comp. with full ported 990 GM iron heads, SuperChiller, B&M 420 blower with twin 800 cfm Holley carbs. With 9 PSI boost on 91 octane made 850 HP at 6500 rpm. Boat ran 92 MPH and you better have BIG balls to run it!

well.. figure out what I can do with what i got and a cam change, and we wills ee if its worth it!! I have some other things that need done, if there is money left, I want to change cams, what do you think I can get hp wise with my current other parts?

460 CI with 110CC domes
Merlin heads, I still need to verify runner size but last we talked I think we were thinking they are the 345cc runner (huge)
420 cams as of now... 228/236
Holley single plane intakes
800 cfm Holley HP500 carbs

heads are put of the box right now and I swear compression is 8.4:1 from what I remember..

as of now I have pushed the Mistress to a best of 65 MPH @ 5000 with 24P Quicksilver props... actually good numbers for a Mistress with the power it has..

let me know thoughts Dean... thx

Piston domes come more in the range of 20-50cc's. A .030" over 454 zero decked with 24cc domes would be 10:1 compression in 119cc chambers.
What pistons/compression is your buddy running that made 521hp with the stock heads and dual plane and that Edelbrock cam? What stock heads did he have? Anything else?

The Big-block Chevy Merlin head casting number is "I-043," followed by a "B," "C" or "D" indicating the port size. Merlin heads are also stamped "World Merlin" on the outside of the cylinder head, above the exhaust ports.

B=345cc
C=310cc
D=269cc

Not sure his piston, I know they are .30 over, 9.5:1 stock 400/420 heads, I will look for cam number, I swear it was a 236/242 duration cam, high .570 lift, edelbrock rpm dual plane intakes, and 800 cfm holleys..our boats are the same, he also has a mistress, got a best of 66.1

I will have to see if I have any pics to see, I swear when I was trying to figure it out there was no tell tale way besides CC them..

One of my engines have the KB KB-203 pistons, 12 cc domes looks like, no idea what I was thinking 110 cc lol

the other engine has the forged TRW same dome, I dont have that part number handy yet..

Prob a 2399 piston. Those pistons domes sizes are pretty much what came in a 420, 365, 400, etc.

If the blocks never been surfaced(pistons .020 in hole), or the heads, using a standard .039 Fel pro gasket, 119cc combustion chamber, that would be around 8.65:1. I'd imagine though the blocks and heads have probably seen some surfacing in the past, esp since they already been bored. Prob somewhere real close to 9:1 as they sit.