The right props?

[cnthings]

I am currently running Mirage plus 15 1/4 " 19 pitch props on twin Yam 225 EFI's ( 289 intrepid). Loaded full evrything turns 4000-4100 @ 30-31 kts( 34-36mph) burn 24-26gph, WOT 5300-5400 @41-42kts(47-48mph) burn 38-39gph. Do these number seem right or should I try to tweak the props?

[Canazes9]

I'm certainly no expert on the large rigs like yours but the numbers your quoting seem really hard to beat w/ the motors you've got (not a crack, their just not the higher efficiency hpdi's or 4-strokes, but really some of those motors would be hard pressed to get that kind of efficiency on a boat that size.)

[cnthings]

They are more efficient then I would have thought, could be the stepped hull. They do like the oil though.

[Reel Escape]

I am currently re-propping my 29 catamaran w/same motors. if i could hit your numbers i'd be real happy. i think you're in good shape!

[First Light]

You props are right where they should be. Your engines are 5500 rpm engines, so if you are turning 5300-5400 WOT "loaded full" you will turn 5500 with a lighter load, so if it were me, I'd leave the props alone.

[rpbolling]

Cnthings, whats your outfit weigh? I have a similar post "Do I need to change props". I may need the exact prop you are running. Are they 3 or 4 blade? Thanks. Looks like your numbers are pretty good.

[cnthings]

I don't trailer so I do not have exact weight. Intrepid lists the hull only @3200#. I would guess loaded full fuel(240gal) ice, etc... 7300-8300 lbs, props are 3 blade. I posted thinking the difference between my cruise and WOT was not enough. I've been reading too many posts of CC's doing 55-60 mph.

[First Light]

If you want that kind of speed you'll need to put a pair of 250's on the back.

I'd kill for performance like that!

Fast--but not THAT fast--Jeff

[Knot Tight]

Your number look pretty good to me our boats are probably similar in weight and hull except mine is a little heavier probably. Your cruise numbers are a little better mine does 32-35 mph at 4400rpm's and your topend is a little lower but my ficht's run up to 6k rpm's and it will do 50-51 mph at those rpm's. I am going to swap my lower units to see if that impoves either of those numbers my fichts will burn less gas than yours efi's but your numbers look pretty good.

[cnthings]

Thanks for the responses--looks like I am not changin anything. Maybe re-condition the props. Repower once these engines fall off the transom.