Hi, everyone! I've been browsing the site as a guest for a while now, and I finally signed up because I need some advice. I recently purchased a 1986 Chaparral 198 CXL (cuddy) with a "3 year old" Non Vortec GM crate motor and a 2 barrel Rochester carb. Engine runs great, but boat seemed sluggish. It has a Merc Alpha One outdrive with the 1.81 gears. Today I took off the prop (because I sharpened it on a rock over the weekend haha) and discovered it has a 15 inch, 23 pitch cupped Michigan propeller on it. I know that's not the right one, but I'm curious as to what is. WOT on the boat only gets to about 4300 RPM, and the boat hurts to reach 40 MPH. It will not plane off with 2 passengers, unless one goes up in the cuddy. From what I can tell, the boat weighs 2900 LBS. Math I've done says thats a slip percentage of over %25....
I mostly plan to cruise in the 25-35 range, and would like to get the RPMS down around that area (30 MPH is about 3600 RPM). I don't have much need to go faster than low 40's.
I think I'm going to go with a 4 blade prop since I'm not overly interested in top speed, I just dont know what to go with. There are not many marinas in my area, as I live in Mass and fun is illegal here, so trying one out before I buy Isn't really an option.
I'm also considering putting the edelbrock 4 barrel intake and 500 CFM carb on it, and was curious if anyone had any insight into that. I know its the wrong forum for that, and I apologize in advance. Thanks for any input!
I mostly plan to cruise in the 25-35 range, and would like to get the RPMS down around that area (30 MPH is about 3600 RPM). I don't have much need to go faster than low 40's.
I think I'm going to go with a 4 blade prop since I'm not overly interested in top speed, I just dont know what to go with. There are not many marinas in my area, as I live in Mass and fun is illegal here, so trying one out before I buy Isn't really an option.
I'm also considering putting the edelbrock 4 barrel intake and 500 CFM carb on it, and was curious if anyone had any insight into that. I know its the wrong forum for that, and I apologize in advance. Thanks for any input!
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