what is the max rpm a 250 pro xs should turn

[brad webb]

I have a 1998 bass cat jaguar just bought a new 250 Pro xs I was breaking it in this weekend and was following the manual word for word I was on my last hour and I went slowly into wot and the rpms hit 6025 and i still had more trim was running 78.7 mph gps imideitly backed off to 5000 and finished my break in. Would like to know if that is bad. manual said 5850 to 6000 at wot.I am running a 26 tempest plus prop. was wondering if I needed more prop. or can this motor turn more than 6000 rpms any info would be great.

[EuropeanAM]

Brad:

The rev limiter on these engines shouldn't be viewed as a "fixed number"- but rather a "window of perhaps 400-500 RPM's".

Depending on various factors (including LOAD), the limiter may kick in earlier, rather than later (in an attempt to avoid a perceived "impending engine overspeed").

Recommended propping RPM is 5500-6000 RPM's. The HARD limiter has varied from 6300-6400 over the years.

In many cases, if propped carefully, and trimmed gradually at WOT, the engine may be cable of reaching 6370, and running there for extended periods.

Provided that you're not activating the limiter... this is acceptable. However, since the engine makes it's PEAK TORQUE and HORSEPOWER in the 5800-6050 range, it would be best to prop it into that range.

You might consider raising prop pitch... or even trying a 26P Fury.

[brad webb]

Thanks don once again helpful as usual

[rwthunder]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by EuropeanAM &raquo;</td></tr><tr><td class="quote">Brad:

The rev limiter on these engines shouldn't be viewed as a "fixed number"- but rather a "window of perhaps 400-500 RPM's".

Depending on various factors (including LOAD), the limiter may kick in earlier, rather than later (in an attempt to avoid a perceived "impending engine overspeed").

Recommended propping RPM is 5500-6000 RPM's. The HARD limiter has varied from 6300-6400 over the years.

In many cases, if propped carefully, and trimmed gradually at WOT, the engine may be cable of reaching 6370, and running there for extended periods.

Provided that you're not activating the limiter... this is acceptable. However, since the engine makes it's PEAK TORQUE and HORSEPOWER in the 5800-6050 range, it would be best to prop it into that range.

You might consider raising prop pitch... or even trying a 26P Fury.


</td></tr></table>

Wow now there is some useful info. I have an Alpha 211 running a 24P Fury and alone i can ture 6400 @ 74 mph....I was wondering why the rev limiter didn't go off until 6450....i always did think i was propped to low but i wondered why the limiter wasn't buzzing....now I know!!! Think i need to go to a 25P Fury...what would u think?

[brad webb]

from what don said that sounds right and might get 2 mph more

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by rwthunder &raquo;</td></tr><tr><td class="quote">

Wow now there is some useful info. I have an Alpha 211 running a 24P Fury and alone i can ture 6400 @ 74 mph....I was wondering why the rev limiter didn't go off until 6450....i always did think i was propped to low but i wondered why the limiter wasn't buzzing....now I know!!! Think i need to go to a 25P Fury...what would u think?</td></tr></table>

Rusty:

Is that figure coming from an ANALOG Tachometer, or from a Smartcraft Instrument?

Analog tachometers are NOTORIOUSLY innacurate.

[rwthunder]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by EuropeanAM &raquo;</td></tr><tr><td class="quote">

Rusty:

Is that figure coming from an ANALOG Tachometer, or from a Smartcraft Instrument?

Analog tachometers are NOTORIOUSLY innacurate.


</td></tr></table>

Analog tach

[EuropeanAM]

Smartcraft Instrument (such as a MercMonitor) would be a very wise investment. It will give you a DEAD ON accurate tachometer reading.... along with TONS of other useful (and important) information.

THEN, you'll know what RPM's you're really turning, and can more accurately determine what, if any, prop changes are appropriate.