Hello, since every time I have made a post on here I've had lots of helpful input, I would like some prop selection opinions before I make a purchase.
-1988 Ciera 2455 purchased with 432hrs and a severely damaged 5.0 (305) OMC engine from non winterization. I decided to repower with a 5.7 as Bayliner has a tendency to under power their boats. I ended up building a Vortec 5.7 with ramjet cam and a Volvo Penta high rise Intake (4bbl), converted to the Delco EST Voyager ignition system. So anyways, a substantial upgrade probably around the 300hp mark (just an uneducated guess
)
Anyways, I finally got it put together and out for a water test this week and wow! ON plane within seconds, after cruising at moderate rpms for an hour, I decided to push it a little harder. Watching the rpms climb...and climb....short story long, around 5800 rpms with the factory 15.25X15 prop! Topped out at 38mph on the gps at around 4600 and just seemed to cavitate at anything above that with the trim all the way down.
What I would like help with is opinions on a prop. I know I need to jump up in pitch, but should I go to a 17 or even try a 19? And also diameter? I don't want to destroy the low hour smooth running OMC outdrive with too much torque as its a fairly heavy boat.
Thanks and look forward to hearing your thoughts!
-Doug
-1988 Ciera 2455 purchased with 432hrs and a severely damaged 5.0 (305) OMC engine from non winterization. I decided to repower with a 5.7 as Bayliner has a tendency to under power their boats. I ended up building a Vortec 5.7 with ramjet cam and a Volvo Penta high rise Intake (4bbl), converted to the Delco EST Voyager ignition system. So anyways, a substantial upgrade probably around the 300hp mark (just an uneducated guess
)Anyways, I finally got it put together and out for a water test this week and wow! ON plane within seconds, after cruising at moderate rpms for an hour, I decided to push it a little harder. Watching the rpms climb...and climb....short story long, around 5800 rpms with the factory 15.25X15 prop! Topped out at 38mph on the gps at around 4600 and just seemed to cavitate at anything above that with the trim all the way down.
What I would like help with is opinions on a prop. I know I need to jump up in pitch, but should I go to a 17 or even try a 19? And also diameter? I don't want to destroy the low hour smooth running OMC outdrive with too much torque as its a fairly heavy boat.
Thanks and look forward to hearing your thoughts!
-Doug
