I would not recommend the V6. HP is not the only issue. Torque is also
needed to get on plane. The V6 does not have the torque. I would stay w/
the 5.7L and go w/ an EFI for the fuel economy.

--
Tony
my boats and cars at http://t.thomas.home.mchsi.com
"John H" wrote in message
news
On Mon, 07 Mar 2005 15:26:20 -0500, Dave Hall
wrote:

On Mon, 07 Mar 2005 14:46:59 -0500, John H
wrote:

On Mon, 07 Mar 2005 13:23:13 -0500, Dave Hall
wrote:

Dave, if you were considering repowering a boat currently powered by a
5.7L
Mercruise, with Alpha 1 outdrive, what engine(s) would you consider?

That depends.

Are you repowering to replace a clapped out engine, or are you simply
"upgrading"?

I would replace what was there with a similar replacement, that way
there's a minimum of hassles, and potential incompatibilities.

If upgrading, remember that the Alpha 1 drive is not rated for more
than 300 HP, so unless you were upgrading to Bravo drives too, I'd
stay below 300 HP.

Dave

It would be because of a clapped out engine, in a few years or so. I'm
already
considering what to do with my boat when the engine goes, if I don't sell
it to
trade up while the engine is still pretty sound.

I'd love to have a bigger boat, but I really have no need for one. I like
the
roominess in the back of the outboard Grady 22'er, but I also like the
convenient 'bait table, extra seats, storage, etc.' offered by the engine
cover
of the Mercruiser. However, $70K for the Grady isn't, in my opinion,
justified
by my needs.

So, the option is to hang onto the boat and repower when necessary. I'd
though
maybe the V6 EPI or the 5L V8 might be suitable replacements. Both would
weigh
less than what I've got, I think, yet deliver a tad more horsepower.

Just thinking...


John H

"All decisions are the result of binary thinking."

On Mon, 07 Mar 2005 23:56:49 GMT, "tony thomas" wrote:

I would not recommend the V6. HP is not the only issue. Torque is also
needed to get on plane. The V6 does not have the torque. I would stay w/
the 5.7L and go w/ an EFI for the fuel economy.

Thanks, Tony. I assume your torque comments apply to the 5L V8 also?


John H

"All decisions are the result of binary thinking."

Yes. The 5.0L does not come close to the torque of the 5.7L engine. Cost
will not be that much more and the extra acceleration will be well worth it.

--
Tony
my boats and cars at http://t.thomas.home.mchsi.com
"John H" wrote in message
...
On Mon, 07 Mar 2005 23:56:49 GMT, "tony thomas"
wrote:

I would not recommend the V6. HP is not the only issue. Torque is also
needed to get on plane. The V6 does not have the torque. I would stay w/
the 5.7L and go w/ an EFI for the fuel economy.

Thanks, Tony. I assume your torque comments apply to the 5L V8 also?


John H

"All decisions are the result of binary thinking."

On Tue, 08 Mar 2005 00:30:28 GMT, "tony thomas" wrote:

Yes. The 5.0L does not come close to the torque of the 5.7L engine. Cost
will not be that much more and the extra acceleration will be well worth it.

Thanks again!


John H

"All decisions are the result of binary thinking."

Hi Guys,

Thanks for all your helpful comments. I see I'm not the only one who's
goat this brain cruncher to worry about.

As Tony suggested, I would luv to go with twin diesels, but the only
units I know of which can be mated to a Sterndrive are the Marine
Diesel V8s sold by Performance Parts Technicians (PPT). Not only would
their high torque require switching to expensive Bravo drives, but they
list for $15K. Not new enough for there to be rebuilds on the market
either.

So I'm still looking hard, and I mean HARD, at replacement gas engines.
It seems smarter to swap the 5.0 Mercruiser 200HP engines for rebuilt
5.7 Mercruisers to get extra torque, running at cruising speed with far
less throttle.

However, I read a post in another forum from a fellow who swapped his
5.7L for a 5.7 MPI unit and lost performance plus got worse gas
mileage. This was apparently due to the higher torque curve in the high
horsepower engine. Max torque was only reached at 5000rmp in the 300HP
engine, while the old carb engine reached its own Max torque at far
lower rpms, giving a bigger kick thanks to its far better midrange
torque.

I guess what I'll have to do is find the torque curves for each variant
of the Mercruiser 5.7 sterndrive I/O engines, and pick the one which
has the best low to midrange torque, forgetting what become useless
considerations of dual carb, four barrel carb, throttle body or
multiport injection.

Thanks for advice on what you'd do. Horsepower upgrades just aren't
going to cut the mustard, and plopping in 454 Crusaders probably won't
help the gallons per hour much in a relatively light 10,000 lb. planing
hull cruiser.

So it's back to the drawing board now...

Rich

wrote in message
ups.com...

So I'm still looking hard, and I mean HARD, at replacement gas engines.
It seems smarter to swap the 5.0 Mercruiser 200HP engines for rebuilt
5.7 Mercruisers to get extra torque, running at cruising speed with far
less throttle.
Rich

If you must repower the best bet out there IMO is the 383 Chevy. The motor
in my truck has over 400 lbs. ft. torque between 2000-4000rpms. And its
more fuel efficient than the 5.0 it replaced.

Rich

Hi Rich,

That 383 Chevy sure sounds great -

But even if by miracle it could be mated to a Mercruiser Sterndrive
(anyone hear of that?) it would have way too much torque for AlphaOne
drives.

Thanks, but it looks like I'm back to the drawing board.

(the other) Rich

You might check out some aftermarket performance shops for marine
applications and see if you can find a cam that will give you the most
torque and hp at the 3000 rpm mark. I am sure someone makes a cam that is
designed for this purpose.

--
Tony
my boats and cars at http://t.thomas.home.mchsi.com
wrote in message
ups.com...

Hi Guys,

Thanks for all your helpful comments. I see I'm not the only one who's
goat this brain cruncher to worry about.

As Tony suggested, I would luv to go with twin diesels, but the only
units I know of which can be mated to a Sterndrive are the Marine
Diesel V8s sold by Performance Parts Technicians (PPT). Not only would
their high torque require switching to expensive Bravo drives, but they
list for $15K. Not new enough for there to be rebuilds on the market
either.

So I'm still looking hard, and I mean HARD, at replacement gas engines.
It seems smarter to swap the 5.0 Mercruiser 200HP engines for rebuilt
5.7 Mercruisers to get extra torque, running at cruising speed with far
less throttle.

However, I read a post in another forum from a fellow who swapped his
5.7L for a 5.7 MPI unit and lost performance plus got worse gas
mileage. This was apparently due to the higher torque curve in the high
horsepower engine. Max torque was only reached at 5000rmp in the 300HP
engine, while the old carb engine reached its own Max torque at far
lower rpms, giving a bigger kick thanks to its far better midrange
torque.

I guess what I'll have to do is find the torque curves for each variant
of the Mercruiser 5.7 sterndrive I/O engines, and pick the one which
has the best low to midrange torque, forgetting what become useless
considerations of dual carb, four barrel carb, throttle body or
multiport injection.

Thanks for advice on what you'd do. Horsepower upgrades just aren't
going to cut the mustard, and plopping in 454 Crusaders probably won't
help the gallons per hour much in a relatively light 10,000 lb. planing
hull cruiser.

So it's back to the drawing board now...

Rich

Hi Tony,

I've checked the google groups for info on 5.0 engines, and apparently
the stock cam is already the one which gives the best torque at 3000rpm
(please correct me if I'm misguided).

So it looks like I'm back to square one - which version of the 5.7 or
another sterndrive compatible engine - if anyone has suggestions.

Cheers,

Rich

On 8 Mar 2005 18:46:35 -0800, wrote:


Hi Guys,

Thanks for all your helpful comments. I see I'm not the only one who's
goat this brain cruncher to worry about.

As Tony suggested, I would luv to go with twin diesels, but the only
units I know of which can be mated to a Sterndrive are the Marine
Diesel V8s sold by Performance Parts Technicians (PPT). Not only would
their high torque require switching to expensive Bravo drives, but they
list for $15K. Not new enough for there to be rebuilds on the market
either.

I had 5 Cat 5966 diesels in my 49' Commando. man would that boat
cruise.