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280eagle
09-03-2007, 08:34 PM
I have a 1999 Eliminator 280 eagle with a merc 502/Bravo 1 drive that has a 4 blade 24P S.S. prop. that tops out at about 4000 rpm @ WOT and about 4200 if trimmed. At this rpm, boat speed is about 48-52mph. I've check the throttle cable/linkages and found no binding (Butterfly flaps open full as expected). Does anybody know if this rpm is all I should be expecting from this set up? Past 454's that I've driven have topped out around 4800-5000 rpm.
Thanks

Zimm944
09-03-2007, 09:51 PM
Something sounds wrong. I have a 28 eagle xp with a 496 HO Bravo 1x and a 22p 4 blade. My boat runs 65mph at 5100 rpm's.

DMOORE
09-03-2007, 10:14 PM
After running the prop slip for your boat assuming you have a 1.5 gearset I input: 24pitch, 4200rpm's, 52mph, and got 18% slip.
You may wany to either have the 24pitch labbed or go down to a 22, in order to let the motor rev a bit more. BTW, when is the last time the boat had a full tune. You'd be suprised what a difference a propper tune up (plugs, wires, timing ,ect...) can do for performance. Always check the basics first.
Darrell.

cfm
09-04-2007, 03:39 AM
Assuming engine is stock...............and before seeing if engine issues.....
Stock 502MPI should be propped for 5000-5100rpm at WOT. HP500 I believe is 5200rpm.
First thing to do is call Eliminator and see what prop they put on these when new.
What is your outdrive's gear ratio ?
While waiting for these answers check to make sure your tabs are pulling all the way back up and outdrive trim is working correctly.

MACHINEHEAD
09-05-2007, 05:14 PM
yes