Exhaust Take Two
Moderators: CaptPatrick, mike ohlstein, Bruce
Exhaust Take Two
After listening to a few boats at PT Judith I decided to reconfigure the exhaust, moved it to the outboard stringers. Went with a centubular muffler and a bronze 6" through hull at the transom. Opened up area for two 48" fish/ice boxes..Thanks for all your suggestions. Should make for a much better layout, after looking at Brewsters boat, I realized that you can never have enough ice/fish storage...BH
1966 31 Bahia Mar #316-512....8 years later..Resolute is now a reality..Builder to Boater..285 hours on the clocks..enjoying every minute..how many days till spring?
- Harry Babb
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oh my god bob i hope i did not influence your decision---ha,ha .the 6" bronze exhaust are bulletproof and available from freeport marine,800-645-2565.you can get 1 lenth of 6" exhaust hose cut in half with 6" vernatone mini max muffler will be perfect fit to boat with the added surge tube insurance by way of "fiberglass shield" in front part of muffler.sort of a one way muffler in common words.
capt.bob lico
bero13010473
bero13010473
Scot, I got the bronze 6" from Hamilton marine, and yes Bob you did influence my thinking a bit....Harry...that peel n ply works great just take your time and get the air bubbles out...the better you do that the better the finish...I will get you a roll, for the turbo flanges...Bruce, thanks for the input...like you have said before..sytem by sytem step by step...doin my best at each step...I just follow the lead of the faithful.BH
1966 31 Bahia Mar #316-512....8 years later..Resolute is now a reality..Builder to Boater..285 hours on the clocks..enjoying every minute..how many days till spring?
- Harry Babb
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now that's the exhaust!
1977 B31 (315 Cummins) Build thread --->https://www.thehulltruth.com/boating-ho ... model.html
2010 Key West Bay Reef | 150 Yamaha
1986 Bertram 28 260 Mercruisers [SOLD]
2010 Key West Bay Reef | 150 Yamaha
1986 Bertram 28 260 Mercruisers [SOLD]
that was my so who saw them on the shelf 7 years ago ." dad this is the real deal" 6" bronze exhaust tough ass instead of fiberglass out the back,a real nostalgia look a true battlewagon. so i took his advise and i love the look .bob you have to agree they look tough ass on a 31 bertram!!!
capt.bob lico
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- scot
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Ok that's it, I want one of those. The site doesn't list them...the Buck A catalog does not list them either? I suppose I can do the old fashion thing and actually pick up the phone and speak to a live person
Is it a 17 degree flange? I believe the 4" shows 90 degree or 17 degree angle options.
Is it a 17 degree flange? I believe the 4" shows 90 degree or 17 degree angle options.
Scot
1969 Bertram 25 "Roly Poly"
she'll float one of these days.. no really it will :-0
1969 Bertram 25 "Roly Poly"
she'll float one of these days.. no really it will :-0
- In Memory Walter K
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What I have seen is the side/corner ones are more trouble than they are worth. If not done properly, they can add back pressure, lessen forward thrust, structurally compromise the transom and often stain the hull sides with exhaust soot. I think that what is pictured is just "Bertram Perfect". Walter
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Mufflers
Hey - awesome job. Where did you get those mufflers. I have a a 31 Northcoast with 3208T (320HP) Cats. There are just straight fiberglass tubes going from engine to transom outboard of 2 large indeck fishboxes. There is quite a rumble from the engines without mufflers, but i really dont have room for normal inline mufflers. I found a marine exhaust guy in FLA that made "linear" mufflers similar to the ones in your pictures...but they were basically for much larger boats...they would glass on smaller hose sizes (6" in my case) but the outside diameter of their smallest size is still 10 inches. ...those things in your picture look like a perfect solution (if they can handle the HP from the Cats)
awesome looking job!
Joe
awesome looking job!
Joe
- scot
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Joef,
I am certainly no "muffler sizing guru" but it may have more to do with exhaust volume and less to do with hp. Your 3208's are something like 636 cu in engines, that's a bunch of spent gas coming out!
I believe I recall that JP's 6BTA's are 330hp and run a similar set up, but 6B's are only 360 esh cu in.
I am certainly no "muffler sizing guru" but it may have more to do with exhaust volume and less to do with hp. Your 3208's are something like 636 cu in engines, that's a bunch of spent gas coming out!
I believe I recall that JP's 6BTA's are 330hp and run a similar set up, but 6B's are only 360 esh cu in.
Scot
1969 Bertram 25 "Roly Poly"
she'll float one of these days.. no really it will :-0
1969 Bertram 25 "Roly Poly"
she'll float one of these days.. no really it will :-0
bob this is what i did for the mini-max muffler installation. nice rumble out the exhaust but quiet in the cockpit.the cockpit floorboards clear the mufflers by only 3/4" but it is easy and it works.in my opinion i beleive the rubber exhaust keeps the cockpit slightly quieter then fiberglass.
capt.bob lico
bero13010473
bero13010473
Hey guys,
this is a budy of mines company, i didnt know they did wet exhaust of this size, i have no idea how much but it may be something to look at.
http://www.maximsilencers.com/marine-we ... -MP11.html
this is a budy of mines company, i didnt know they did wet exhaust of this size, i have no idea how much but it may be something to look at.
http://www.maximsilencers.com/marine-we ... -MP11.html
JoeF, I called centex and asked them for the part #s they really dont list them any where, pat pending, I just remember JPs post. Same on the bronze through hulls look on the buck algonquin site, get part #s and order from local supplier. I used the 9 degree angled ones not the flat ones. The whole system laid out really nice, now its on to the stainless elbows, and thanks to Harry I can get started, custom made turbo flanges shipped right to your door...NICE work Harry...I have already made the fish boxes Ill post some pics when I get them in.
Bob will the waterline vary alot from each boat? Or should I do a dunk and mark to get it right? By goin bronze I moved the exit point UP 2 1/2 inches...and they look tough...flap or no? to complete the battleship look.BH
Bob will the waterline vary alot from each boat? Or should I do a dunk and mark to get it right? By goin bronze I moved the exit point UP 2 1/2 inches...and they look tough...flap or no? to complete the battleship look.BH
1966 31 Bahia Mar #316-512....8 years later..Resolute is now a reality..Builder to Boater..285 hours on the clocks..enjoying every minute..how many days till spring?
Scott, part # 00tea600 for the 9 degree down, from Buck algonquin site. I ordered them from kellogg marine not hamilton, but any buck algonquin distributor should have no problem on a special order.BH
1966 31 Bahia Mar #316-512....8 years later..Resolute is now a reality..Builder to Boater..285 hours on the clocks..enjoying every minute..how many days till spring?
bob you ask me a question with alot of varibles.with NEW iron 6 cylinder the water line will be along the chine edge with half tank of fuel.that line is about 1/3 up from the bottom edge of the 6" exhaust hole.the problem is imron does not like salt water when painted on bronze it will in time bubble up.that being said lets go to options with a bronze flange you have the options of using a exhaust flap i chose not to because the centek minimax muffler part # 1050600 allready has a full shield in the front that stops a water surge that is why it is a one way muffler.i do not know if you have this built into yours so i can`t answer the flap question.size of muffler is determine by horsepower of engine not displacement of engine. 6' exhaust is the minimum for a 330hp cummins 6bta-m3 engine.i show you my exhaust i have no fiberglass at all nor do i have 90 degree angles what i have is 6" 316 ss 70 degree angles at bottom with high heat blue silicon joints .a custom sprinker head and 41/2" 316 ss hot pipe.you have to get that exhaust out of the engine for maximum performance. i desigh mine mine to have near 0 HG. cummins says not to exceed (3")you will have to eventually prove it to cummins for warrantee.
capt.bob lico
bero13010473
bero13010473
Bob H,
You'll like the Centek's. Since installing these the folks at the marina we used have done another 3 or 4 boats with these units. Both on 270 B series and the newest QSB's. While tuna trolling we can talk and listen to music without blasting out the pit or yelling at each other.
After about 1100 rpm you hear engine noise from the boxes, not the exhaust. Around 1600 the exhausts have a dull drone and then as you get into the turbos the noise comes from the boxes themselves. With the Bahia your going to want to insulate in front of the engins below decks, the boxes and all around to the point of your air intake source. The mechanical engines have quite a rattle to them, not to mention a significant turbo whine (its even louder if you use a K&N style intake filter).
Nothing beats carrying minimal coolers while heading offshore. Nice choice.
You'll like the Centek's. Since installing these the folks at the marina we used have done another 3 or 4 boats with these units. Both on 270 B series and the newest QSB's. While tuna trolling we can talk and listen to music without blasting out the pit or yelling at each other.
After about 1100 rpm you hear engine noise from the boxes, not the exhaust. Around 1600 the exhausts have a dull drone and then as you get into the turbos the noise comes from the boxes themselves. With the Bahia your going to want to insulate in front of the engins below decks, the boxes and all around to the point of your air intake source. The mechanical engines have quite a rattle to them, not to mention a significant turbo whine (its even louder if you use a K&N style intake filter).
Nothing beats carrying minimal coolers while heading offshore. Nice choice.
KR
JP
1977 RLDT "CHIMERA"
JP
1977 RLDT "CHIMERA"
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