I did one mail order tune that worked out good for blackhawk aka scott elgas, he had a single mefi3 hp500 efi innovation, he ported his heads and drove boat w vacuum gauge and 02 meter, i would make changes to his program and upload to a spare ecu, mail it to him, drive it, give me numbers, make changes to his ecu, pass in mail etc, got fuel dialed in perfect, was a little hassle but did work, fwiw, smitty

I did one mail order tune that worked out good for blackhawk aka scott elgas, he had a single mefi3 hp500 efi innovation, he ported his heads and drove boat w vacuum gauge and 02 meter, text me numbers, i would calculate map vs bpw, i would make changes to his program and upload to a spare ecu, mail it to him, he'd drive it, give me numbers, make changes to his ecu, pass in mail etc, got fuel dialed in perfect, was a little hassle but did work, fwiw, smitty

It helped that he lived one mile from a test lake and was one day away via mail. He would use the boat meanwile and just kept it out of rpm bands where it was rich or lean, Smitty

??????????????

1st I live in Columbus, Ohio and I was told to use ASM. I didn't even check any threads or reviews, I just went that direction to flash my ECU, which I had to send it back once and then Jim (@ASM) ended up sending different programs to put in because it wouldn't idle. I went from a Volvo Penta 454 with MPI to a HT502 crate engine because Schumaker Performance recommended it said everything would bolt on and work.They used my 454 cam and because It does have oval ports is why I guess. The engine has 10 hours on it and 3 of those hours were under load and spun #7 bearing and ruined the crank while I was breaking it in softly. Now Jim says, he will sell me a 502 and use my heads. Of course Chevy will not honor any warranty because it is not intended for marine. I spent $6K on the HT and another $4K to get it running. Is this right in line on how ASM operates? Any thoughts if the ECU could have caused this to happen? It was running good and sounded good until.... Also wondering if I should have this one fixed and run it, or fix it and sell it?

Did you reuse your oil cooler, what happened to old motor? Did stock oil bypass on ht motor get swapped for the higher differential one? Did you take off the stock 4 or 5 or whatever quart pan on new motor and put on a marine oil pan? I had a new zz502 on engine stand and it had a clearly smaller oil pan than a 454/502 mercruiser does.

Yes we did. The old engine is at buddies house and I am thinking I may drop my HT off at Chevy at about 25 MPH and make it goes right through their front doors! Thinking I may take the 454 and bump it up and put it back in. Yes we used the one off the 454. Yes, the 12 qt pan from 454 went onto the HT. Yes, I was told the ZZ is not a good one. But from everyone I have been in contact with, I was made to look (in my eyes) like a complete ass for letting them talk me into this POS HT502. 16K and 3 hours on this boat this summer. Going to be an interesting winter t see what I end up doing. 454 has 310Hp and thinking I am going to end up 500 and change. not looking to haul ass, because our boat is heavy. 99 Four Wins 254 Funship which is VERY rare I guess.

I second that about Eddie Young!! Just be prepared when you call to chat for a bit, because he loves to talk about boats in general. lol He is the go to guy for tuning in my opinion.