DIY Head Porting?

[Lubak572]

I have the heads off my 6.2 gm marine long block I recently installed in my boat due to a broken rocker arm stud. Is it worth it to port/polish them myself. I have all the tools and time.

 

[Bondo]

I have the heads off my 6.2 gm marine long block I recently installed in my boat due to a broken rocker arm stud. Is it worth it to port/polish them myself. I have all the tools and time.

Ayuh,..... Not really,...... Boat motors are restricted by the exhaust manifolds, 'n the piping beyond,.....

 

[Lubak572]

Ayuh,..... Not really,...... Boat motors are restricted by the exhaust manifolds, 'n the piping beyond,.....

I'm running Hardin Marine exhaust and I upgraded my stock 5.7 to 6.2's.

 

[Scott Danforth]

yes, if you are bored and have the tools

not much of a gain with a stock bump-stick and 5000 RPM limit

on vortec heads, blend the intake bowls and runners, leaving the passages rough (carbide only) while tapering around the valve guide boss

the exhaust should be bowl blended and port matched (not gasket matched) and sanded with tootsie rolls to 220 finish

This will help some throttle response and pick up some flow in the 3200-4500 RPM range

for detonation control, the combustion chamber should have all the casting marks removed and sanded with 180-220 grit minimum.

 

[Tail_Gunner]

Well since you that far along...add a xm 270 cam....debur the heads and spin that up to 6000 rpm. Your outdrive is quite robust, I don't think 6k is to unreasonable...you won't know if you don't get. Lol.

Ohh I see that's been done.