I see Imco has a -3" shorty lower out. I called Imco and found out it'll work on the merc upper, but prop size is limited to 14-14.5". I was also told that a couple of guys had modified the mercuy upper a little to make room for larger wheels.


I know I could buy the SC upper for the -3" lower and not have any clearance issues with props- it has a step built into the upper on that model. Just wondering if anyone running one with the merc upper?

Not running a -3 on a merc upper but I'd think limiting yourself to a 14" diam. prop would not be too good of an idea on a raised prop shaft height, that doesn't give you many choices IMO. I'm running a -2 and with my set up larger diam. props seem to work best with the higher shaft height.

I have the -3 upper and lower. Love it. I may be selling the set up as it will not hold up to the new motor.

I was figuring that up to 14.5" prop would be ok. I'd think a mirage plus 27p or29p would work fine at 2" below the pad on my 21sb. Dunno, maybe I'm thinking too much like an outboard owner

I was hoping to see, or hear about what mods have been done to the merc upper for larger prop clearance with the -3 lower, in case I had to go that route.

I was told that the Merc upper needs to be modified to accept a -3 Imco Lower. Ya might want to double check just to be sure.


Darrell.

The bravo upper needs to be machined out to have some clearance for prop,can only run about 14 diameter prop if not machined,did one for a 25 checkmate works great,any machine shop can handle the machining,or you could cut it out with saw and sand flat by hand

Thanks, MGD!

You got any pics? I assume that the stock merc lower can still be used, and it leaves a notch on the upper by the rear?

Do the -3 lowers come with any kind of cav plate?

Sorry for the ?s, but inquiring minds want to know!

No, the cav plate is on the upper. The -3 uppers do come with a cav plate it turns up to clear the prop. I may have a picture

This is the best I had.

Well you might get away with a 27p m+ at a diam of 14 3/8 but the 29p m+ has a 15" diam. I tired a 27 p m+ and it was a foul handeling SOB. I'm running a labbed 29p m+ but the diam. is 15" don't think that's gonna work for ya without some mods goodluck