Tige 21v - Engine replacement questions

[jgray]

I have the unfortunate task of needing to pull and rebuild the 350 MPI from my 2001 21v.

The boat has been an amazing boat and I have no problem rebuilding it to stock and putting the motor back in... However... A little more power...

My initial though is to put a 6.2 marine long block in, if I do this do I need to have the ECU calibrated? From what I can tell it is a MEFI-3 ECU, or Mercruiser 555 (they seem to be the same.) The boat has always ran rich as all up at elevation (5280 daily, lowest its ever been is Powell.)

Or is it worth trying to track down a complete newer LS setup with v-drive and drop it in?

[snowmandopeman]

just out of curiosity whats wrong with it and how many hours did it have?

[Grebva3]

Check out inboard solutions they do this quite often and are very knowledgeable.

[jgray]

5500+ Hours on the engine, I knew it was going to need replaced sooner or later.

It cracked the block on the starboard side from freeze plug to freeze plug. The front plug blew out but the rear stayed in.

[snowmandopeman]

wow 5500 hours, serious testament to these engines.

[boatwakes]

To avoid headaches and save time/money etc, swap like for like. The MEFI 3 and 555 ECM's are not at all the same. Complete set ups are best but partial engines from mercruiser are around $8300. Remember, you get what you pay for.