212 shabah 5.7 mercruiser alpha 1 prop help
 

I am a new owner of a 1998 212 shabah with a 5.7 mercruiser alpha 1 outdrive , i currently have a 21 pitch prop aluminum, wanting to purchase a good (stainles)all around prop for top end and out of the hole power, i dont even know the recommended rpm for my boat. the current prop at around 40mph just over revs, but maybe a 21 pitch stainless prop wont, dont know , just need a good economical stainless all around prop, please help this new mariah owner. i have been recommended a (vengence) prop but i have no idea

Re: 212 shabah 5.7 mercruiser alpha 1 prop help
 

Your 5.7 should run between 4400 - 4800 rpms at WOT and you should be somewhere in the low-mid 50's. Unfortunately there is no prop that will give you optimum top speed along with optimum hole shot as you will always trade off one against the other. Ideally you find the compromise spot that best suits what you want to use the boat for. The 21" prop would be a cruising prop on that boat. A 19" 3 blade would give decent performance at both low & high speeds.

Here's Iboat.com's prop selection page for your motor. Lots of choice there.

Re: 212 shabah 5.7 mercruiser alpha 1 prop help
 

Don't forget the best of both worlds" auto shift props. A friend had one and was like two different props in one. Great hole shot and top end. Of course, he spent a couple of G's on it!

Re: 212 shabah 5.7 mercruiser alpha 1 prop help
 

$2k on a prop? not on your life.

Re: 212 shabah 5.7 mercruiser alpha 1 prop help
 

Yah I know what you mean. I've seen them as low as 1295. Still---:shakehead:

Re: 212 shabah 5.7 mercruiser alpha 1 prop help
 

I run a 3 blade stainless 13.75x21p Vengence on my 5.7L Alpha combo, 1.5 drive ratio. It's a good all around setup. I've never pulled a wakeboard (tubes and skiers) but I have no trouble staying on plane down into the low 20's. I cruise 35 mph at about 3200 rpm. WOT gives me 4600rpm and about 53 tops. I'd say it's a good match to my 202.