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View Full Version : what prop for new 500hp engine?


BacDoc
06-14-2002, 08:11 PM
Just had a new Marine Power X500 ( Marine Powers version of HP500)installed to my 22'classic this week.The mechanic said he took it out for test/break in ride with a 23p prop. He said it was hitting the rev limiter at 5300rpm and speedo said 71mph ( he said he checked at lower speed with gps and speedo was accurate). The mechanic suggested going to a 25p prop. I was under the impression that with 500hp I would be using either a 27p or 29p prop. I told the mechanic this and he said "no way." I have a Bravo 1 drive and high performance Gill manifolds and risers. What do you guys think? This Marina that is installing the engine doesn't do much high performance stuff. I just read the post with Tantan 99 and his 454 370hp running a 25p prop at 5100rmps.
Thanks
Dan
PS I will be installing the duel ram external steering next. As suggested by many on the board
HP 600SC
06-14-2002, 08:31 PM
BacDoc, sounds like you must have a 1:50 ratio
drive right? 25 mirage plus is THE prop.
Dont even think of the 27 as it is a small diameter "weirdo" and the 29 is too big pitch for
your set up. The SE 22's with the 500 EFI's
ues the 25 mirage plus. I spent many hours trying over 10 props for that setup. The Factory "Lab"
version is worth the extra money.
BacDoc
06-14-2002, 08:59 PM
HP500-22
Thanks for your reply.I think my drive is 1.5 I will check for sure mon. Is that picture your hp500 with 25p prop. If so is your drive 1.5 or different ratio.
Thanks
Dan
HP 600SC
06-14-2002, 09:07 PM
Doc, not sure what photo you are refering to but
my drive is a 1:65 with a 29 Mirage Plus "Lab"
tweeked to a 30" pitch.
roadtrip se
06-14-2002, 10:37 PM
Ted,

Just curious here. Are you saying that going with the IMCO shorty allowed you to step up five inches in pitch from the factory built 500 boat?
WOW! I've looked at your pictures too, over the past year. Your X isn't any higher than mine in the stock 22, so that ain't it.

Please give away just a couple of secrets o'wise one.

Todd
HP 600SC
06-15-2002, 07:58 AM
Todd, no I'm not saying that at all.
There are several other factors involved in my
particular setup:
Hull modifaction IE: blueprinting, centerline balance and CG. Different gear ratio (1:65 see above) engine upgrades, Lab prop, custom exaust and a couple of minor things (trim tab size and height) And of course a few hours of dialing everything in.