97 Mariner 175 magnum efi?

[open2hardwater]

I'm looking to put a 200hp block/power head on my 175. I've looked into it a little bit and for the most part they have all the same parts. If I'm not mistaken the 150, 175, and the 200 in the 97 mag efi all have the same block. Any input would be greatly appreciated. Thanks

 

[Dukedog]

They all will inter change with tha same clamp, trim, exhaust adapter and down housing. Tha "main" horsepower difference is tha blocks/porting, differences in all three......Some "sleeve manufactures" sell a generic replacement sleeve for all three that works fine but they don't leave Merc production that way. There is some difference in a coupla "bolt on" parts also..

 

[open2hardwater]

They all will inter change with tha same clamp, trim, exhaust adapter and down housing. Tha "main" horsepower difference is tha blocks/porting, differences in all three......Some "sleeve manufactures" sell a generic replacement sleeve for all three that works fine but they don't leave Merc production that way. There is some difference in a coupla "bolt on" parts also..

Would there be any BIG/EXSPENSIVE problem that I may run into?

 

[open2hardwater]

I should've stated that I will be buying a rebuilt 200 power head. Should be bolt on ready, wondering if most of my electical components will transfer over from the 175 to the 200.

 

[Dukedog]

Everything will be fine. Tha only thing that might be a "slight" concern would be tha ecu. Its a crap shoot. Mercs ecu's can be different. What I mean is that their fuel curve can be little different from unit ta unit even when they are supposed ta be identical for certain horse powers. It won't be enough ta make a difference when used on what its supposed ta be on but may or may not run worth a crap ona a different horse power motor. Clear as mud huh! Example. Same motor, 2 or 3 ecu's for that motor. 2 might run 'bout tha same but 1 might give ya a little more warm fuzzy than tha other 2...

Whats tha number on your ecu? What year 200?