Above water exhaust on a OMC V-4?

[zx1216]

Hey, i have seen the cast units from bob's machine shop and was wondering if there was any way to do this on my 81 johnson 115? Could i just drill holes in the mid to let the exhaust out? I do like the option of pluging the holes when you don't want it so loud. Thanks for any help!

[FlowMaxx]

V4 and V6 midsections are the same, so buy the one from Bobs, it will work fine. Nice looking boat, by the way :D

[YELLOWSS]

a very long time ago i had a 140 johnson. i drilled two 1/2" holes one on the left and one on the right side of the mid. a old racer i new did it all the time. it was just a little louder. at a idle the holes were just under the water. it never cracked in the 4 years i had it... small holes though compared to bobs.
there are really now hp gaines from doing this!!!!!!!!! just noise.

[ROLF]

Keep in mind when most rigs are set up correctly your propshaft/LU is out of the water anyway and exhust is pretty much open as well.I have run both standard and open exhust on V4 OMC and did not see any
mph gains with the open exaust.It is above the water when running at low speeds around docks and homes and generally just draws attention and pissed off neighbors.The Taylor 16" mid exhust on a 3.0 OMC is a WICKED sounding and is worth pissing off the folks however.Check out some of "Lakers" posts he has some really sharp exhust mods on V4's.Some of the other members will chime in but I did not see ANY gains on a pump gas V4 but they do look cool when done correctly.
Rolf

[Matthew Ramirez]

buy doing this u get a quicker hole shot nothing to do with top end

[zx1216]

Thanks for the help guys, i knew there wasn't much of a performance gain but i think it would look and sound sweet. I like the option of plugging the holes so i can go hot rod around and then plug them when i want to put around.

[zx1216]

V4 and V6 midsections are the same, so buy the one from Bobs, it will work fine. Nice looking boat, by the way :D

Thanks:) Where in wisconsin are you located? Ever get up to the Minocqua area?

[winter]

I had a Hydrostream V-King with a 235 rude and it had relieved exhaust ports in the mid section. All i know is it made a lovely sound, got some attention when you lit it off on the docks. But while running it wasn't a whole lot louder. I'd say do it, but i'd think there is a science to how big and how many holes you drill.

[76baja18ft]

You can drill some holes right above the cavitation plate to relieve the exhaust.. you might remove the lower unit to do it if u arent familar with where the exhaust flows threw the lower unit...You could also fab up a block off plate to cover the holes when you dont want it so loud..

http://img2.putfile.com/main/11/30916463842.jpg

[FlowMaxx]

Thanks:) Where in wisconsin are you located? Ever get up to the Minocqua area?

I get up to minocqua once year. Three lakes once or twice a year for a week. I will be at the Three Lakes shootuot in June.

[FlowMaxx]

Best 20" exhaust mid out there is the Chris Lake custom offshore mid :D:D:D:D

http://aycu35.webshots.com/image/50354/2005269853220678409_rs.jpg (http://allyoucanupload.webshots.com/v/2005269853220678409)