I am rebuilding the motor for my 79 formula. The block is being freshened up with a .030 overbore. I will be using stock crank, stock rods, clevite 77 bearings, Speed Pro hypereutectic pistons with teflon skirts, flat top, 4 valve reliefs. I am going with a comp cams double roller timing set. The cam will be the Comp xtreme marine Flat tappet 262 grind. Duration 262° Intake / 268° Exhaust Duration @ .050'' Lift: 218° Intake / 224° Exhaust Valve Lift w/1.5 Rockers: .462'' Intake / .477'' Exhaust. That rounds out the bottom end. For the top end I have a rebuilt set of 906 casting Vortec heads that have been modified for .500 lift. I have self aligning rockers. For an intake I was thinking an Edelbrock Air Gap, fed by my existing 1409 Edelbrock carb. I have brand new GLM center rise manifolds for the exhaust. I have a few questions.

What head gaskets should I use? I was told Fel-Pro 1003.

Intake gaskets?

Should I go to through hull exhaust?

What speeds should my F18 reach (went 55mph @ 5000rpm with a 21p mirage plus when stock)?

What other tips do you guys have?

Btw roller cam would be nice but its not in the budget. Any help is greatly appreciated.

What exhaust are you plan on running? Any engine build starts with exhaust. You can throw all the money in the world at it, if you don't have a good exhaust you are wasting money.
Roller is the only way to go. It only cost a few more dollars. Boating is not cheap hobby. Good luck with your build.

GLM center rise exhaust going through the prop. Might do through hull. Roller cam is just not in the works right now.

Def go thru hull, I've never done tests but that y pipe can't flow very well.