I want better speed and performance

Stinnett21

Chief Petty Officer
Joined
Jun 24, 2012
Messages
557
Is your engine not the 250/260hp at that age ?
anyway....some guys here have went for the big 16x16 black max ally prop, with some success. Similar top speed to the 14x17” black max but way way better out the hole.
I know of a bayliner 2855 with a 5.7 250 and alpha...he has one and I was seriously impressed with it out the hole for such a big boat.

I'm confused. What does your reference to HP have to do with it? My point was obviously related to longevity/reliability. Let's assume he has a 1/2 hour run to the islands. Are you telling me he wants to run a 5.7 through an A1 G2 at WOT and keep the boat any length of time??? Ain't gonna happen. He's probably waterlogged to some degree anyway. He has an expectation problem not a boat problem. Now I've never been to the Pacific north west but I'm betting those waters are absolutely gorgeous. If I were him I would install a good set of trim tabs, put a beer in a Yeti, get just on plane and let the good times roll. My 2 cents.
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,348
I'm confused. What does your reference to HP have to do with it? My point was obviously related to longevity/reliability. Let's assume he has a 1/2 hour run to the islands. Are you telling me he wants to run a 5.7 through an A1 G2 at WOT and keep the boat any length of time??? Ain't gonna happen. He's probably waterlogged to some degree anyway. He has an expectation problem not a boat problem. Now I've never been to the Pacific north west but I'm betting those waters are absolutely gorgeous. If I were him I would install a good set of trim tabs, put a beer in a Yeti, get just on plane and let the good times roll. My 2 cents.

Mmm. Ok I’m confused now....

i just suggested that a 5.7 of around that age would likely be most likely a 250 or 260hp motor.

also confused by your suggestion that an alpha one gen2 wouldn’t handle a 5.7 carb driving it...it’s a very popular set up and has been for decades. They manage it just fine.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
I'm confused. What does your reference to HP have to do with it? My point was obviously related to longevity/reliability. Let's assume he has a 1/2 hour run to the islands. Are you telling me he wants to run a 5.7 through an A1 G2 at WOT and keep the boat any length of time??? Ain't gonna happen. He's probably waterlogged to some degree anyway. He has an expectation problem not a boat problem. Now I've never been to the Pacific north west but I'm betting those waters are absolutely gorgeous. If I were him I would install a good set of trim tabs, put a beer in a Yeti, get just on plane and let the good times roll. My 2 cents.

Let's make some assumptions here (because everyone else is)...

Boat's 1995, so I'll assume (until told otherwise) that the engine is also 1995. That makes it a 5.7L (non-vortec), 2 barrel carb producing 235hp (that's what the book calls out), and there were no 4 barrel variants of the 5.7L engine for that year... The Alpha One Gen II is as good as or better than, an Alpha One, and by the book, good to 300hp... And I know a couple of guys who bombed a 350cu in to about 340hp, running through an Alpha One that I built for them. I know the guys, and they only have 2 speeds, fast and faster. And that was in a HEAVY 7m hull. For them to collect a little 'air' wasn't unusual. The drive lasted for as long as I knew them (about 10 years).

I have a 4.3MPI (220hp by the book) with an Alpha One Gen II, and I have run at WOT for more than 14 nautical miles non-stop on quite a few occasions, with no problems.

Chris.........
 
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QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,348
Let's make some assumptions here (because everyone else is)...

Boat's 1995, so I'll assume (until told otherwise) that the engine is also 1995. That makes it a 5.7L (non-vortec), 2 barrel carb producing 235hp (that's what the book calls out), and there were no 4 barrel variants of the 5.7L engine for that year... The Alpha One Gen II is as good as or better than, an Alpha One, and by the book, good to 300hp... And I know a couple of guys who bombed a 350cu in to about 340hp, running through an Alpha One that I built for them. I know the guys, and they only have 2 speeds, fast and faster. And that was in a HEAVY 7m hull. For them to collect a little 'air' wasn't unusual. The drive lasted for as long as I knew them (about 10 years).

I have a 4.3MPI (220hp by the book) with an Alpha One Gen II, and I have run at WOT for more than 14 nautical miles non-stop on quite a few occasions, with no problems.

Chris.........

At the risk of an argument...why would a 1995 make it exclusively a 2 barrel carb ?
there were defo 4 barrel 260hp 5.7s in 1995. And I suspect also 2 barrel 250hp weren’t long after
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Don't argue with me, argue with the book. I'm using Merc service manaul #17 as reference. That book is for both Vortec and non-Vortec engines. Vortec started in late 96, so 95 is non-Vortec and the non-vortec 5.7 engine was only available as a '5.7L' at 235hp, making it a 2 barrel carb. From 93 on, Merc only has 2 barrel or EFI/MPI variants for the 5.7L.

The 2 barrel 250hp was a (5.7L) Vortec engine but only available with a Bravo drive.

The forum software is broken at the moment or I would post a screenshot to show you the pages in the manual.

Chris.....
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,363
At the risk of an argument...why would a 1995 make it exclusively a 2 barrel carb ?
there were defo 4 barrel 260hp 5.7s in 1995. And I suspect also 2 barrel 250hp weren’t long after

merc was pushing the efi motors vs the 4-barrel carbs
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,348
merc was pushing the efi motors vs the 4-barrel carbs

I’m sure you’re right Scott. But I’m almost sure that there were 4 barrel carbs in 95 and also 4 barrel 5.0 carbs with 230hp....very close to a 235hp 5.7.

Although I must admit...I’m not sure I know of a 5.7 95 engine with 235hp that made it over here. Never heard or seen one here at that age.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
I’m sure you’re right Scott. But I’m almost sure that there were 4 barrel carbs in 95 and also 4 barrel 5.0 carbs with 230hp....very close to a 235hp 5.7.

Although I must admit...I’m not sure I know of a 5.7 95 engine with 235hp that made it over here. Never heard or seen one here at that age.

NO 4 BARREL 5.7L SINCE 1993!

Manual #17, spec page for non-Vortec engines...

350Spec.JPG
 

harringtondav

Commander
Joined
May 26, 2018
Messages
2,442
We all have different boating lifestyles. Sometimes we take a lady with us, sometimes we take the whole family. Obviously, no single prop will satisfy us all the time. Pick one for the average conditions and make do with all the other ones.

Right on. Our river house basement looks like a prop shop. I have 21, 22, 23" props, alum and SS, three and four blade. I get max speed at spec WOT throttle with the 23". But I can tell the engine is working harder at our normal cruising speed, and I don't spend much time at 52 mph in our little boat. So I use a 21P 90% of the time. The boat jumps out of the water on hole shot, and purrs along nicely when cruising. But it will over rev at WOT, so I use the right hand rev limiter.
 

cptbill

Senior Chief Petty Officer
Joined
Oct 6, 2012
Messages
762
Like they say "There is no substitute for cubic inches"
 
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