"Rick & Linda Bernard" wrote in message ...
There are two speed marine transmissions that should all you to build RPM's
quickly at slow speeds and still give you a good top end.

I'm betting this guy does not have extra space between his 5.7 and
outdrive for a transmission :-)


"Paul" wrote in message
able.rogers.com...
I think the "dog coming out of the hole" comment was based on putting a
bigger prop on it to take advantage of the increased top end. But without
that power down low then the it would be overpropped until the turbo
kicked
in.

wrote in message
...
Hemicuda wrote:
: So from what I can summarize from the above posts are that the turbo
: will probably work great while cruising and at top end but will be a
: dog coming out of the hole. This is a dumb question but I thought

It wouldn't be a "dog coming out of the hole". It'd act mostlyl like a
naturally aspirated engine.

Turbos work well in marine applications, one of the side benefits is that they
also make great mufflers. Here is a good thread on a marine turbo project:

http://forums.hotboat.net/ubb/ultima...c;f=3;t=000483

Thanks for all the comments. A marine trans is not an option so if it
comes to that I will definitely go a different route. I am not
looking for absolute power in this set up but instead looking fora
viable alternative to shoving a 502 in an express cruiser. My main
goals for the project would be improve performance of a small block
without the disadvantages of big block. As to the issue of fabbing a
set-up I should be able to get all the fittings I will need and mig
them all together. The cooling issue does concern me because I don't
want to build jacketed headers but I was thinking about possibly
tracing them tubing that water is pumped through and then rapping the
piping. As long as I have enough flow through the tubing the water
should stay liquid and cool the system. Since I am looking at putting
this system on a 5,000# boat loss of accelaeration will be a big deal
because I would still like to have the functionality to use it for
water sports. I understand some of the reasoning about the
acceleration problems. Is there any slippage of the prop in the water
during acceleration. If I can get it to about 1000-1500 rpms and put
some small turbine housings on the turbos I should be into boost by
this point. The small housings will kill my top end but that
shouldn't be a problem seeing as the engine probably won't see more
than 4500 RPM. Are there any technical articles on the start-up
torque and HP requirements of boats that I could read? Thanks for the
help.


572 wrote in message . ..
Turbos work well in marine applications, one of the side benefits is that they
also make great mufflers. Here is a good thread on a marine turbo project:

http://forums.hotboat.net/ubb/ultima...c;f=3;t=000483

"Hemicuda" wrote in message
om...
Thanks for all the comments. A marine trans is not an option so if it
comes to that I will definitely go a different route. I am not
looking for absolute power in this set up but instead looking fora
viable alternative to shoving a 502 in an express cruiser. My main
goals for the project would be improve performance of a small block
without the disadvantages of big block. As to the issue of fabbing a
set-up I should be able to get all the fittings I will need and mig
them all together. The cooling issue does concern me because I don't
want to build jacketed headers but I was thinking about possibly
tracing them tubing that water is pumped through and then rapping the
piping. As long as I have enough flow through the tubing the water
should stay liquid and cool the system. Since I am looking at putting
this system on a 5,000# boat loss of accelaeration will be a big deal
because I would still like to have the functionality to use it for
water sports. I understand some of the reasoning about the
acceleration problems. Is there any slippage of the prop in the water
during acceleration. If I can get it to about 1000-1500 rpms and put
some small turbine housings on the turbos I should be into boost by
this point. The small housings will kill my top end but that
shouldn't be a problem seeing as the engine probably won't see more
than 4500 RPM. Are there any technical articles on the start-up
torque and HP requirements of boats that I could read? Thanks for the
help.


572 wrote in message
. ..
Turbos work well in marine applications, one of the side benefits is
that they
also make great mufflers. Here is a good thread on a marine turbo
project:

http://forums.hotboat.net/ubb/ultima...c;f=3;t=000483

Perhaps something like this:
http://www.amazon.com/exec/obidos/tg...glance&s=books

Mark Browne

I already have Hugh McInnes book which is really solid on the
fundamentals of Turbo'd engines. Does Bell's really add that much?
The guys at the JYturbo forum speak higher of McInnes book. I am
looking for a little more on the hydro-dynamics of props during the
acceleration of a boat. I am familiar with pumps (my back ground is
an engineer) but I not that familiar with the specifics as they apply
to boats. I want to get some rules of thumb about how much torque and
HP are needed during boat launch so that I can make some guesses about
whether a turbo would work in the application I'm looking at. Do you
know any books concerning that subject? Thanks for the help.

Perhaps something like this:
http://www.amazon.com/exec/obidos/tg...glance&s=books

Mark Browne