Bonzen

FYI you don't have to pull the exhaust to remove the lower valve cover bolts. I have a 454 with stock aluminum valve covers and I have pulled them plenty of times using a 1/4 socket, swivel and long extension.

There's definitely hope for your motor, I also am running the peanut port heads with a large oval port intake and it revs to 4800rpm, and it's a jet boat. I run the COMP cams 226/236 @ .050 hydraulic flat tappet with SRP small dome pistons (10:1 comp) and have zero reversion issues with wet logs.

Fman

Alright so I finally got to call up formula. I got lucky and the boat came with the 454mag.

mike tkach

iTrader: (3)

the block numbers say 1973 to 1990 2 or 4 bolt 454.

Fman

Yeah that's all I could come up with online too. I'll still pull off the intake one of these days to make sure, but I would only hope one would be smart enough to at least re use the better heads if the motor has since been replaced with a standard 7.4

Fman

Alright so a little update as I could still use a little help.

I got a bore scope and the carb is off the boat. Looks like it has rectangular port heads so safe to say its a mag motor. When i pulled the carb the last owner cross threaded the bolts into the intake. The carb could use a go through rebuild.

instead of fixing the intake and getting the carb rebuilt I want to just replace them. What would be a better option for both then what I have? I know more needs to get replaced but thats where I currently sit with it. was thinking the RPM air gap intake and quick fuel 750/800CFM carb? cam and exhaust will also be in the works.

thanks for all your help.

dereknkathy

new intake and new carb 5 to 800 bucks. merc used that intake with 800 holley on the hp500 carb motor. with those pistons and heads. except I don't think they used 2.25 intake valves. rebuild the carb. helicoil the intake bolts. put the 800 saved towards better exhaust, Inconel exhaust valves and a roller cam and lifters with less overlap. oh yeah, then paint the motor blue...

mike tkach

iTrader: (3)

blue engines matter!

BenPerfected

My thought is to just leave it as it is and go boating.

dereknkathy

except for the fact he is running stock merc exhaust. That cam has too much overlap and will suck water from exhaust at low rpm's with that exhaust. So an exhaust with longer distance from exhaust valve to where water mixes with exhaust gas is necessary.

79formula

I had a 454 mag shortblock, Crane 132561 cam, crane gold rockers, Dart knock off single plane intake, holley carb, and EMI thunder exhaust in my 242. It ran low 60s. It was a good combo with some basic, reliable parts. I have been told that cam will even work with stock exhaust.