Old Mercury Info
 

I am rebuilding an old Boat. A made in Canada 245 Grew Hardtop. It is all original and in pretty good shape but my plan is to rebuild all mechanicals. It is a Mercury 188 HP with a Mercury 888 Outdrive. I understand from studying that the 188 is a Ford smallblock and usually a 302. Does anyone know someone, who, really knows this engine? I’d like to step it up, perhaps take what I got and add fuel injection, high performance heads and wharever else needed to boost up the HP. Would anyone know if that 888 drive would take maybe another 75 - 100 H.P.?
Thanks.

888
 

The 888 drive is a MC1. It’s the pre MR. They don’t like anything near or over 300 hp. They had small pinion and thin gear. But Mercury came out with some heavier lower gear sets around 1980 for them, less teeth on pinion so Gear was a little bigger. They have small pinion shaft. Keep HP low and keep oil clean and it should last behind a pleasure boat. Not worth the time and money to put that set up in a go fast boat. If you can find a set of the old Mercruiser manuals 1 & 2 they are yellow orange colored they have all the info on your engine and drive. You can get a newer style MR or Alpha to bolt up. But judging by age of your set up you might be better off going the restoration route better return on your dollar

Can I ask you a few more questions.

Fire away

IMHO its all on how you drive. If you like to beat on your stuff doing hard take offs, yanking in and out of gear, etc, etc you may have an issue with a 888. With that aside a 302 or what the kids like to call a 5.0 you have options. For that matter I killed so many 302's hopping them up and running them hard I was going to put little stickers of motors on the side of the boat like fighter pilots would do for kills. I finally dropped the 302's and went with a 351winsor and was so much happier. All with a 888 drive.

Old Mercury
 

Was the 351 a different block or some 302, crank, cam, heads, carb combo?