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rlj676 06-11-2009 07:33 PM

28 Speeds
 
What does a 28 run with the various engines? I've tried searching and haven't found much.

For example,

A single 500 hp vs 502 twins, etc.

What's it take to run 70, 80 in a single or twins.

Thanks.

MACTIME 06-11-2009 08:42 PM

I have a 1998 28 that had a single 509 blown 725 hp bravo one 1.5 spinning a herring 5 blade

top out at 5400rpm 87mph.

The blown motor has been replaced by a new 502 with similar specs a hp500 with a litlle bigger cam, approx. 550hp.

We have not splashed it but beleive that it should run approx 75-78 and get great fuel mileage

I have been a 28 with twins and it did not ride as well and topped out at 78....stock 502 mpi....too much wait for the length and the drives ride way too high.

this of course is with i/o

cowisl 06-11-2009 08:46 PM

My 28 with twin 300 promax's runs 80

rlj676 06-12-2009 02:40 PM

Thanks guys.

So it seems that 500 hp will break 70?

Also, twin big blocks are too rear-heavy then and a big single is best (or outoards if that's your deal:drink:)?

DareDevil 06-14-2009 12:30 PM


Originally Posted by rlj676 (Post 2886946)
Thanks guys.

So it seems that 500 hp will break 70?

Also, twin big blocks are too rear-heavy then and a big single is best (or outoards if that's your deal:drink:)?

I would say a nice 650 HP BB ,,should get u in the mid 80's easy.

The one that raced back in 98ish did almost 95 !!!:eek:

rlj676 06-15-2009 07:40 PM


Originally Posted by daredevil (Post 2887910)
I would say a nice 650 HP BB ,,should get u in the mid 80's easy.

The one that raced back in 98ish did almost 95 !!!:eek:

That sounds pretty good.:eek:



So nobody knows though what a single HP500 will run?

DareDevil 06-15-2009 10:24 PM


Originally Posted by rlj676 (Post 2888979)
That sounds pretty good.:eek:



So nobody knows though what a single HP500 will run?

U should be in the mid 80's for shure !!!!

rlj676 06-16-2009 04:25 PM


Originally Posted by daredevil (Post 2889168)
U should be in the mid 80's for shure !!!!

Sounds optimistic....but I like it.:evilb:

DareDevil 06-16-2009 06:30 PM


Originally Posted by rlj676 (Post 2889836)
Sounds optimistic....but I like it.:evilb:

It should do it ,,,with the right prop and maybe a shortry,,or extension box !!! 80-85,,the boat is not that heavy.
My old 33 was ~ 6400 # with twin BB and Imco's,fully loaded

rlj676 06-16-2009 06:42 PM


Originally Posted by daredevil (Post 2889956)
It should do it ,,,with the right prop and maybe a shortry,,or extension box !!! 80-85,,the boat is not that heavy.
My old 33 was ~ 6400 # with twin BB and Imco's,fully loaded

If I get this boat I'm looking at it has no external hydraulic steering, so I might go for an exension box (they can have internal hyd seering right?). Otherwise I agree it shouldn't be too heavy at all, pretty light on the amenities.


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