dereknkathy

Tho other disadvantage to 20 to 30 year old heads. Rot. They have water cooled exhaust valve guides. Means very little iron between cooling system and exhaust ports. Almost all rectangle heads after 1971 were marine. They didn't use them in trucks or police cars. I have a set of ported 781's came with my pantera. 20 years in the Hudson River and 15 years sitting dry. I can scrape 1/4 inch thick flakes off inside the water jackets. I can't scrap them, though I did scrap the block, but I don't dare ever run them. And they stopped using real ovals in trucks in the mid to late 70's and they are almost all peanuts. So any ovals you find that did spend their lives with antifreeze need guides and seats.

Mr Maine

People make out like you can just snap your fingers and a peanut port 454 marine engine will make 500 horse. Doesnt matter what you see in a car magazine its not happenin without a lot of work

SB

iTrader: (1)

LOL.

OP still hasn't given us any engine and boat info nor any performance wants/wishes....so what is all the discussions about ?

turbos230

To give you the details is hard now because the engine is still together. But if I could post a picture you will see these are built motors, they have blowers. 572 ci blocks.Very clean and freshly painted but the work was done 5 years ago (50 hrs),it was in storage for 5 years and I am thinking to refresh but juice the heads the most I can and be reliable. The motors have 800 hp but for fresh built 572 with blowers I think there should be more power and I am willing to upgrade things. I am still deciding to go with the blowers it came with or change everything to procharger.

F-2 Speedy

iTrader: (6)

What blowers ? and what block was used for the 572's......do you know what the compression is

JRider

iTrader: (1)

With superchargers (I assume roots?) I don't think you are going to see a lot of bang for the buck sinking $ into heads. You may already have good heads seeing that it is a 572, I wouldnt think it would have standard 088s on it. Be careful with prochargers, if you are really running hard they can and will throw belts. Sounds low on HP for a blown 572, I would think you would be money ahead finding what the cam specs, boost and compression are, then go from there...may be as simple as a pulley change and tuning.

turbos230

I wish I knew how to put a picture, it asks for a link to the picture but the picture is here on the desktop not the internet.
I have to get the information about the compression and I will post it.The other things I will have to ask the old owner for the cam specs and what kind of block it is

But the cam sounds like a good place to look and if it does not have roller rockers I will add that- but probably does. But the engines does seem to be low in power for being a 50 hour rebuild 572 with roots blower

F-2 Speedy

iTrader: (6)

if u upgrade you're membership you can post jpegs

dereknkathy

real blowers blow prochargers away in a boat. sounds like a pretty decent setup already. do a compression and leakdown test. replace the valve springs. you can post pics with a photobucket acct if you don't wanna pay for upgraded membership. it sounds like you haven't run this boat yet. anything close to 1600 hp should get your weenie hard when you hit the gas. get him on the water and decide if you need more power after you see and enjoy what you have...

turbos230

Yes I am going to run it like that for some time maybe 40-50 hours then pull the engines apart because I do want to improve things , like a nervous tick have to play with things. But if you wanted to send your heads to a wizard to make them at 100% of their capacity what shop is a good option ??