Mounting a 175EFI on a 200EFI mid with 200 tuner? Is it safe? Will I gain anything?

[Gamefish451]

So long story short, I have a 92 175efi, and I would like to swap it over to a 98 200efi mid and lower (it had an FF block original on this mid). I picked this up fairly cheap with the intentions of converting my Mariner into a Merc. My main concern is will I hurt the 175 powerhead if I just swap it over to the 200 mid and lower? I’m not too familiar with the porting and cooling side of the motors, or if the 200 exhaust tuner is gonna hurt me or not as well.

[Dave Strong]

It will work, doubt you will see huge gains maybe a bit.

Dave

[KIRCHNER]

Merc & mariner are the same, execpt color and decals. i dont think youll gain anything. most likely same tuner.

[nitro_rat]

175 efi's usually have the long tuner that goes all the way to the bottom of the liner. It will breathe better with the 200 tuner!

[Gamefish451]

Merc & mariner are the same, execpt color and decals. i dont think youll gain anything. most likely same tuner.

Yeah I know, my boat came with the Mariner and it’s just looking old as the years go on. Scored a deal on an alien hood and lower cowls with the mid and gear case really cheap. So I figured instead of painting everything on my Mariner black to be a merc... why not just buy a base gasket and swap the power head over 🤷🏻*♂️.

[nitro_rat]

Whatever you like, I go out of my way to make sure most of my junk is Mariner gray. Everybody runs a Merc...

[KIRCHNER]

I think the mariner hi-po engines look awsome. Graphite grey/orange race cowls really cool.