Prop for '88 223 7.4
 

I'm overspinning a 21 Mirage on my BBC 223 and can turn 5000+ if not careful. I've been thinking of trying a 4 blade to get more lift and compare it to a 23" Mirage. Any ideas appreciated.

I use a bravo 1 four blade 22 pitch on my 242, that may get you down a few rpms.

Yes that was the other one I was hoping to also try. Have you ran any other prop on the 242?

I think a 23 mirage plus would be best or maybe a 23 Rev 4. Both are bow lifting props. A bravo prop is more of a stern lifter.
Do you ever boat on the kennebec?

No I'm on Sebago and Long Lake. This boat loves to porpous at mid range speeds unless I drop the tabs. I can drive out of it and it's fine at wot but it's that midrange I'd like to improve. Would stern lift help or hurt?

I have driven the 206 and 242 with many different props and haven't noticed a porpoise issue. Is your drive trimmed too high? I think your best bet would be to try a few props if you can and see what you like, but that boat should want a bow lifting prop. I do know people run bravo 4 blade props for better planing and mid range, but usually slower on the top end because it doesn't lift the bow as good. On a step hull, doesn't matter as much because you don't need to lift the bow, so they work great.

You're right about too much trim and that's just me trying to air it out. I can trim in a bit and it settles down but just feels like a lot of boat in the water. I guess I'll just run it and look for a 23. Thanks for the info.

I am taking a trip up there this weekend for a few days. I have a handful of props im selling. If you pm me I can look and see what I have. I know I have a 23 3 blade in the pIle at least

Masi242, That's a lot of prop for an Alpha isn't it? When are you going Bravo?

Had a 223 for about 12 years, ran a 21 mirage great holeshot , Midrange topend, tried a 23 mirage gained a couple mph top end, Did not like holeshot or midrange, It did turn 5000-5200 wfo with 21but I usually never ran it very long, was still running fine when I sold it. the 23 will bring the rpms down to 4800 to 5000 so if you intend to run wfo for long runs you may want to go that route

Did the 23 really turn it into a pig on the holeshot or was it acceptable? How did it effect the midrange? Maybe the 21 is the best compromise after all?

Yes I had it labbed down a little it runs great, I have had it on there for years.

Ran o.k. on holeshot with 23, but was a bullet with the 21, midrange quicker with the 21 also. Just for the record I dont know if my engine was modded only external mod was stainless risers,
but on the old pressure speedo it would hit 70 mph, with any load, only ran the 23 with 2 aboard hit 71-72, I know the old speedo was perhaps 6-9 mph on the happy side,
but still pretty stout performance for a 330? ran 5200 with 21 around 4800 to 5000 with 23. flatout left a lot of boats on holeshot with 21, but every prop is a little different. GOOD LUCK

Yeah I'd knock a few mph off that speedo. If you had a 1.5 Bravo you'd be at -2% prop slip.

Yeah, Only used the speedo as reference to max performance and rpm, Never bothered to gps or slip calciulate, Point being on my 223 I liked the performance of the 21 best, However boat eng usage, and props all a little different. One other thing both my props were mirage not mirage plus. Try as many props as you can get your hands till you find the best for your application, But 21 and 23 should be in the ballpark. 223 is a great little offshore enjoy your ride

I definitlely appreciate your info. I called my prop a Mirage in the original post but it's actually the QS knockoff Thunderbolt. Almost the same as a Mirage, no vents and no logo. I heard the Mirage might have more cupping but not sure.

I actually have a 23 thunderbolt on my 206 right now. It is vented (vents are plugged) and says quicksilver down the side. The prop including cupping looks and runs the same as a 23 mirage +. The non plus has less cup.