Usually those heads would have raised numbers on them. Any idea as to what those number are?
all 6 cyl, are 70 psi hard to bleave a engine that big would have so low compression how do they get 200hp out of that sure dont sound likley
I wasn't asking about compression numbers. I'm asking about the actual 6 digit numbers that would be imprinted on the heads. These are usually cast numbers that are raised rather than being cast into the metal.
If on the off chance, you are looking for different heads rather than what your engine normally incorporates, what are the part numbers of the heads you're looking for?
The small bore heads will have numbers ending in 1490.
Bee your engine has the later model heads so it will have more compression, I will get numbers off my heads tonite. Just install the new style and you will be ok .
i am new to boating and im am a dragracer i traded a racecar for this boat i have now i know the first thing i do to a motor for more power is up the compression eather by heads or pistons so thats why i was leaning to the heads i have 1 19ft javelin with this 200gt it is a heavy boat it runs little over 60mph i want some more out of it as my buddy runs off and leaves me he has 150 merc on 18ft light boat i was wanting to up the compression and jet the carbs in hope of running faster motor runs good but the compression is only 70 psi in all 6 cyls and the are the same in all 6 mabey this isnt the best way to go but wanted to try it being it was just a bolt on item mabey i just need a merc thanks for your replys any and all help will go along way thanksLike we talked about before, you need to define why you think you need to do this. It may not be benificial anyway. Those big bore GT heads are pretty good ones.