rpm @ wot

junior1113

Senior Chief Petty Officer
Joined
Jan 29, 2009
Messages
763
93 20' hydrosport deep v 14.25 21 is the prop and i get great speed ranges but wot is at 5000 rpm good or bad
 

ezeke

Supreme Mariner
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Sep 19, 2003
Messages
12,532
Re: rpm @ wot

If the motor is the 1992 200HP, you could go as much as 1000 RPM higher with a better setup or possibly a lower pitch prop. The motor will last longer with a peak of at least 5,800 RPM at WOT.

What is your top speed now?
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: rpm @ wot

21 is a lot of pitch, exactly what motor is it.
 

junior1113

Senior Chief Petty Officer
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Jan 29, 2009
Messages
763
Re: rpm @ wot

92 200 hp evinrude top speed 43 viper prop boat wieghs approx 2600
 

ezeke

Supreme Mariner
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Sep 19, 2003
Messages
12,532
Re: rpm @ wot

If I did the math correctly, you should have theoretical maximum speed of 53 MPH with a 21 pitch prop at 5,000 RPM. At 43 MPH you have way too much slip.

You could probably run just as fast or faster with a 19 pitch prop, have a better hole shot and not lug your engine.
 

Benny1963

Lieutenant
Joined
Sep 17, 2006
Messages
1,476
Re: rpm @ wot

how high are you runnin,
i was runnin ,48 on a 175 crossflow with sst2 14 1/4 x21 at 5000
moved my motor up 1 ana 1/2 cav was level with bottom of transom .
then i ran 53 gps at 5600 went up 1 more inch with no loss of waterpressure
and ran 56 at 5800 with a little left ,went to turbo t1 22p and im runnin full out at 5800 57 gps check your cav plate hight and try to max out your setup
then if ya cant get the revs drop down to 19p.this is on a 17ft mckee
kinda of whaler hull ,but im also runnin smart tabs to keep the bow hop down and plane faster,at lower speed im alittle over my rating hp wize
its rated at140 im 175 at flywheel , not sayin to overrate but it is all i had
 

junior1113

Senior Chief Petty Officer
Joined
Jan 29, 2009
Messages
763
Re: rpm @ wot

i put a 14.5 by 19 omc prop now im hitting 5400 rpm @ wot with same max speed ?????? any better or do i need to go with a 17 with a good cup thanx for all the help guys. motor seems like its as high as its going to go w/o cav
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: rpm @ wot

You are in a much better situation than you were with the 21 pitch prop.

All other things being equal, if it were mine, I would go for the 17 pitch or perhaps a stainless propeller if the 19 pitch is aluminum.

It is not so much about getting more speed, but maintaining the speed without lugging the engine. At 5800 RPM, your theoretical maximum speed would be 50 MPH with a 17 pitch prop.
 

junior1113

Senior Chief Petty Officer
Joined
Jan 29, 2009
Messages
763
Re: rpm @ wot

ok so with a 19 pitch prop im at 43 mph @5350 rpms wot. i just checked the rev limiter sticker wich is at 6700 rpms any help appreciated im leaning toward a mirage 17 i also checked on moving the motor up and it is up all the way without puting in new bottom holes ty
 
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