Best Mods for a 1978 Blackmax 150hp

[ILLandowner]

Any opinions for the best 2-3 modifications on this motor? I believe it is 100% stock. You know best Bang for my Buck?? Would like to start watching for parts to get a feel for what they sell for and watch for any bargains I might come across.

[Capt.Insane-o]

Switch to horizontal front half and cutting the heads to 140 psi will bring the biggest gains. Also going to a 2.4 200 bell tuner from the long 150 tuner, netted over 200 rpms on top end and was the only time I've seen a tuner change gain anything.There is some cutting/grinding/welding involved. After that having the block finger ported.

[ILLandowner]

Thanks for the suggestions. I'm also wondering if a small ear chopper 22 pitch prop would work OK on it? I had purchased a few props to try on my inline-6 and wondered how it would work on the Blackmax. I don't have a prop for it yet, unless the chopper I have would be a good starting point.

I should say, I'm going to throw it on the Checkmate Enchanter I bought to prove out this engine, then potentially mount on my glastron CV16.

[Capt.Insane-o]

You have a PM too.

[ILLandowner]

You've got a PM in return.