RPM Issues on my volvo twin gxi 6 cylinder engines

[al1026]

I have been working thru issues on my new purchase of a 2003 Regal 28.6 Commander
Twin 4.3 GXI
Had a marine shop replace fuel pumps. Easy enough too do but needed other mechanical issues addressed and since this boat is a new purchase felt it was best too let shop go thru boat.
They put engines on computer, compression tests, shift cables replaced, took for water test.

After river test, they said boat runs good except takes too long too get up on plane, and max RPM were 4000. ?
They said RPM should be around 4800
Upon inspection they said wrong props are on boat. ??
Boat has duo stainless F 5 props that the shop said is generally for 8 cylinder
They said F 2 should be this boat.

They did say long term, strain on engines, burning more fuel.

They indicated each set of props is around $ 1600.00

My indicated my stainless F 5 props are good, and could sell for $ 700.00 ?

Does anybody have same engines and experienced what I am ?


Can pitch on F 5 be changed too F 2?
Aftermarket available ??

thanks for info

 

[Tail_Gunner]

You want to prop the engine to 4800/5000rpm running at 4000 wot is not at all good for the engine. Duo's are expensive yes but they also provide top performance...A bit of a luxury item so to speak. watch for used props on ebay they are around.