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WildestDream
 
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Default Group newbie with a prop question...

or if u have an old automotive analizer ie: dwell, volt, amps & Tack, u
could just hook it up and let somebody drive it and see if it jives with
your boat tack. I have 2 old one's havent used them in awhile. No u can't
have one sorry.

"jaybird" wrote in message
. ..

"WildestDream" wrote in message
...
My rpm on a 5.8L 14.5x19 prop is about 4600 to 4800 right in range with

the
spec's in the manual, I get about 32 mph wot. my manual says a 7.5 liter
ford should get 4400-4800 rpm at wot. I would check your rpm gauge with

a
reliable gauge. a 7.5 should idle @ 700-800. That may tell if your gauge

is
anywhere close @ low rpms. every inch of pitch increase is a decrease of

200
rpm & vice versa, putting a 23 pitch prop on will decrease your rpm 200

rpm,
unless it cavitates or ventilates, than the rpms will go up and the

speed
will go down, I don't know what the theoretical speed increase would be.

btw
I have a 26' cruiser @ 5200 lbs. dry, alittle under powered I know. but
gets 4 adults up easy. You may need a tuneup or a new gauge 3200 sounds

real
low.


I'll double check the book, but it seems to me like your range is about

what
mine should be too. It just sounds like I need to head to the dealer and
get the gauge looked at, then go with the RPM from there.

Thanks.

j.