Did OP ever tell us where he is??? (Present best speed)

Yes. It's in the first post. 47mph.

Sorry, I missed that.. I bought this same boat new in 1987... They renamed it 215 Sundowner. I ordered it with a 230 HP Mercruiser( 305 Chevy with a Quadrajet). It ran 43-44 with stock power and bottom paint. In 2007 I repowered it with an Indmar crate motor and stock exhaust(Vortec Chevy 350) they stated roughly between 300-320 HP. Hit 53 MPH on GPS.. Only other change was that I had to go up in pitch on the prop...
That said: I would not want to go faster in that hull... Still a great boat after 27 years...

Alright, did some digging as I remember a few rag mags beating the crap out of stock Goodwrench 5.7's.

Stock compression is 7.8:1 with it's 76cc heads.

For them to get 9.0:1 compression with 64cc heads they needed to use .015 headgaskets.

Here's a good article om modifying this motor:
http://www.corvettefaq.com/c3/goodwrench/gm3502.htm

Awesome cause you can give the OP great info - especially propping and what not.

The alpha will be fine on that boat up to 300 hp. 350 if you take it easy out of thew hole

Chris

Heads are way to big so is the cam as well as crancking compression possibly do to the cam and lazy intake flow. IK brodex smaller port version would be best and a cam with less at .050 duration and about .500ish lift. Raising the X dimension possibly a big help also

I moved the X up 1 7/8" on my Four Winns and it made a tremendous difference in speed and handling . When I built a stock engine to put back in it to sale , the boat still ran extremely well and the first guy to test ride bought it .

I have the following head gaskets on the motor:


Fel-Pro 17030
PermaTorque MLS Head Gasket •Small Block Chevy Marine
•Gasket Bore: 4.125''
•Compressed Thickness: .039''
•Compressed Volume: 8.7cc

Small Block Chevy Marine

Have the distributor out and taking it to see what its doing tonight. (where its currently opening up and how far)

After reading:

Here's a good article om modifying this motor:
http://www.corvettefaq.com/c3/goodwrench/gm3502.htm

I see I bought the wrong head gaskets too. Should have went with a thinner one. Wow, I do have a bad combo of parts. Will always ask before I start buying from now on for sure!!!