Gas inboard search

[Bill Childs]

There certainly are plenty of high-speed gasoline inboard engines in the 140+ hp range. But I'm coming up short on new gas engines available in the 50 - 100 hp range. I need an engine with high revs (3500 rpm or so) to spin fast enough to push my light planing boats. I've ruled out most diesels because of their weight and cost.

Westerbeke has a 70 hp four-cylinder gas engine that has a 3600 rpm top end that might be geared properly to do the job - cost is higher than it should be.
<img src=http://www.imagestation.com/picture/sraid202/pa23a178f0145b32d7af046e15f2d7633/efb21e47.jpg>

The Subaru and Mazda marine engine conversion guys are making good progress but want way too much dough at this time for their products.

I've used the Chevy four-banger (120 -140 hp). It works good but is mucho mas power than is needed and is a bit heavy at about 500 lbs.

The people that buy my boats want a new engine with a warranty and parts availability so that rules out rebuilding vintage iron.

Any thoughts on other choices? I must be overlooking some fabulous options hiding out there in the world somewhere.

Thanks,
BarboatBilly

[Bill Childs]

There certainly are plenty of high-speed gasoline inboard engines in the 140+ hp range. But I'm coming up short on new gas engines available in the 50 - 100 hp range. I need an engine with high revs (3500 rpm or so) to spin fast enough to push my light planing boats. I've ruled out most diesels because of their weight and cost.

Westerbeke has a 70 hp four-cylinder gas engine that has a 3600 rpm top end that might be geared properly to do the job - cost is higher than it should be.
<img src=http://www.imagestation.com/picture/sraid202/pa23a178f0145b32d7af046e15f2d7633/efb21e47.jpg>

The Subaru and Mazda marine engine conversion guys are making good progress but want way too much dough at this time for their products.

I've used the Chevy four-banger (120 -140 hp). It works good but is mucho mas power than is needed and is a bit heavy at about 500 lbs.

The people that buy my boats want a new engine with a warranty and parts availability so that rules out rebuilding vintage iron.

Any thoughts on other choices? I must be overlooking some fabulous options hiding out there in the world somewhere.

Thanks,
BarboatBilly

[Bill Childs]

There certainly are plenty of high-speed gasoline inboard engines in the 140+ hp range. But I'm coming up short on new gas engines available in the 50 - 100 hp range. I need an engine with high revs (3500 rpm or so) to spin fast enough to push my light planing boats. I've ruled out most diesels because of their weight and cost.

Westerbeke has a 70 hp four-cylinder gas engine that has a 3600 rpm top end that might be geared properly to do the job - cost is higher than it should be.
<img src=http://www.imagestation.com/picture/sraid202/pa23a178f0145b32d7af046e15f2d7633/efb21e47.jpg>

The Subaru and Mazda marine engine conversion guys are making good progress but want way too much dough at this time for their products.

I've used the Chevy four-banger (120 -140 hp). It works good but is mucho mas power than is needed and is a bit heavy at about 500 lbs.

The people that buy my boats want a new engine with a warranty and parts availability so that rules out rebuilding vintage iron.

Any thoughts on other choices? I must be overlooking some fabulous options hiding out there in the world somewhere.

Thanks,
BarboatBilly

[Charlie Santi]

Is the 3 liter 4cyl Mercrusier motor available as an inboard?

[Charlie Santi]

Is the 3 liter 4cyl Mercrusier motor available as an inboard?

[Charlie Santi]

Is the 3 liter 4cyl Mercrusier motor available as an inboard?

[Bill Childs]

Yes, the 3.0L is the best option I've found so far but it's more power than I want.
These guys put a 3.0L inboard Mercruiser together with either a ZF or BW velvet drive gear:
www.perfprotech.com (http://www.perfprotech.com)
And Marine Power uses the same Chevy four cylinder block to produce a slighly lighter version (more aluminum parts):
www.marinepowerusa.com (http://www.marinepowerusa.com)
Both sources don't offer much insight to these packages on their web sites but a phone call or email to a real person at either place will produce details.

With the same engine (2.5 - 3.0L) you can order a bobtail and make your own inboard by bolting on a damper plate, bell housing,and transmission.
We used a rebuilt 2.5L (120 hp) Mercruiser that started life as a sterndrive application.
<img src=http://www.imagestation.com/picture/sraid200/p73ec734e3b879b565637d9352eb20aa2/f063bbb7.jpg>

It fit very nicely in a 19' Bartender stretched to 20'-5".
<img src=http://www.imagestation.com/picture/sraid198/p535670d727cc046ddf31f1595ac18808/f0d055a7.jpg>

I have a few more of these to build now which is why I'm on a mad search for other engine options. Any and all ideas are appreciated. George Calkins has blessed the stretching and inboarding of his 19' design. We haven't run one yet with the Chevy four cylinder but it should be quite a thrill.
<img src=http://www.imagestation.com/picture/sraid200/pbd834639ed0f5739af19e874d79df3f1/f063bb0e.jpg>

[Bill Childs]

Yes, the 3.0L is the best option I've found so far but it's more power than I want.
These guys put a 3.0L inboard Mercruiser together with either a ZF or BW velvet drive gear:
www.perfprotech.com (http://www.perfprotech.com)
And Marine Power uses the same Chevy four cylinder block to produce a slighly lighter version (more aluminum parts):
www.marinepowerusa.com (http://www.marinepowerusa.com)
Both sources don't offer much insight to these packages on their web sites but a phone call or email to a real person at either place will produce details.

With the same engine (2.5 - 3.0L) you can order a bobtail and make your own inboard by bolting on a damper plate, bell housing,and transmission.
We used a rebuilt 2.5L (120 hp) Mercruiser that started life as a sterndrive application.
<img src=http://www.imagestation.com/picture/sraid200/p73ec734e3b879b565637d9352eb20aa2/f063bbb7.jpg>

It fit very nicely in a 19' Bartender stretched to 20'-5".
<img src=http://www.imagestation.com/picture/sraid198/p535670d727cc046ddf31f1595ac18808/f0d055a7.jpg>

I have a few more of these to build now which is why I'm on a mad search for other engine options. Any and all ideas are appreciated. George Calkins has blessed the stretching and inboarding of his 19' design. We haven't run one yet with the Chevy four cylinder but it should be quite a thrill.
<img src=http://www.imagestation.com/picture/sraid200/pbd834639ed0f5739af19e874d79df3f1/f063bb0e.jpg>

[Bill Childs]

Yes, the 3.0L is the best option I've found so far but it's more power than I want.
These guys put a 3.0L inboard Mercruiser together with either a ZF or BW velvet drive gear:
www.perfprotech.com (http://www.perfprotech.com)
And Marine Power uses the same Chevy four cylinder block to produce a slighly lighter version (more aluminum parts):
www.marinepowerusa.com (http://www.marinepowerusa.com)
Both sources don't offer much insight to these packages on their web sites but a phone call or email to a real person at either place will produce details.

With the same engine (2.5 - 3.0L) you can order a bobtail and make your own inboard by bolting on a damper plate, bell housing,and transmission.
We used a rebuilt 2.5L (120 hp) Mercruiser that started life as a sterndrive application.
<img src=http://www.imagestation.com/picture/sraid200/p73ec734e3b879b565637d9352eb20aa2/f063bbb7.jpg>

It fit very nicely in a 19' Bartender stretched to 20'-5".
<img src=http://www.imagestation.com/picture/sraid198/p535670d727cc046ddf31f1595ac18808/f0d055a7.jpg>

I have a few more of these to build now which is why I'm on a mad search for other engine options. Any and all ideas are appreciated. George Calkins has blessed the stretching and inboarding of his 19' design. We haven't run one yet with the Chevy four cylinder but it should be quite a thrill.
<img src=http://www.imagestation.com/picture/sraid200/pbd834639ed0f5739af19e874d79df3f1/f063bb0e.jpg>