Help!! Not seeing the same speed as last year!!

[Sammyb713]

Hey Everyone!!

First, Let me say THANK YOU to everyone who contributed to the Leukemia Poker Run!! It was a blast!!

Okay heres my dilema..

1993 35 Ft Sonic, hull was Blue Printed by Art Lilly, I have twin 509 Engines built by Jim Benning, I run a 28 pitch prop, boat weighs approx 10K lbs, no arch

Last year..boat hit 79 MPH all day long, with the right trim and half tank of fuel...

This year..I cant get the thing to hit 70mph!!!

Talked to my mechanic he says NO WAY, because he was running next to me in a 292 Formula and they were running every bit of 71-73 mph and I was passing them..

I just yanked the boat out and put it on the trailer..Nose cones were chipping pretty badly..Could it be the drag from them?? I dont know, so I knocked the nose cones off and I am grinding them down this weekend and making them smoothe and narrow again..

What about fuel weight? I have been running on FULL tanks most of the summer..( 160 gallons )

I added external steering over the winter? Could the rams be weighing me down!!!???

Whats the deal??

Just gave the boat a tune up...runs perfect, doesnt run too rich...I have no mechanical issues!! Why cant I get 79 MPH outta this sucker anymore??

My dad is going to change my props to 26 pitch before we put it back in the water..Will it help??

Here is the other thing.. I am going off of a GARMIN GPS 440 or 540 ( somethig like that ) ( its brand new ) my hand held last year was the GPS giving me he 79 MPH output...Now this new GPS is the one telling me I am not getting above 70MPH when I was passing someone that was running 71-73 Mph????!!!

Does the GPS need to be calibrated or something??

Do I need something adjusted?? Engine wise?? Help???

Help!! Help me get back my 79MPH!!! This blonde needs to go fast!!:driving:

 

[Airpacker]

are the tachs reading the same WOT rpm as they were last year?

 

[Sammyb713]

Yes, I am runnin 5100RPM

 

[Davidmnc]

Try another GPS.

 

[Ratickle]

Try another GPS.

What he said. Get a handheld in there and compare.

 

[Geronimo36]

Check the GPS speed settings. Almost sounds like it's in knot or SOG mode.

 

[Griff]

Yes, I am runnin 5100RPM

If you're running the same rpms, then no way you lost 9mph.

FYI.........70 knots=80.6mph.

 

[TMS1155]

My garmin was set for knots when I bought it. Read the book and it will tell you how to change it if thats what is wrong.

 

[MarylandMark]

Have fun with it- have a buddy that has a "80MPH" boat run with you to see you are "only" running 70MPH; then every time you are running together dust their azz!

 

[Sammyb713]

I am checking the GPS tonight...I need to get my speed back!! I really hope it is just the GPS...I guess I will actually have to "read" the manual!

 

[OldSchool]

You don't have to read the manual. Power up the unit, hit the enter button when asked to "agree" with the terms of service. From there, hit menu then scroll down to setup. Look for settings for the speed and select mph. It's that simple!


......or just do like I do and tell everyone that asks that it goes 100 miles an hour.:rofl::rofl::rofl:


For what it's worth, something is messed up with the whole gps system. The current max speed on trip page of my gps is 217.4 mph! I'll take a picture of it before resetting it.

Here is a picture from last November. My boat LOVES the cold fall air!!!!!

 

[Geronimo36]

Craig, I had that same GPS on my Scarab and loved it! I have the smaller unit for the Apache now and that works well also.

I hear ya about the speed blips. Last summer my gps recorded a max speed of 2400 mph on a trip!!