350 Tempest

[Jerry Eisele]

Does anyone have the spec. sheet on the 350 Tempest 1986. If anyone has modified one, what has been successful? Thanks for the input. Jerry :confused:

[jdsdls]

I had one in my old z-21. Its a 350 Chevy 4 bolt main with a forged crank and pistons. It's a solid motor and I lost my Alpha throught it so go easy on it.

[Jim]

I use to own a 1985 18' 2+3 with with a buddy of mine that had a Tempest and it ran great. We had a 40 gallon tank and even with it topped off and with five adults it did 65 all day long. I once hit 73 by myself with very little fuel, didn't have a gps so I'm sure it was a bit slower but I know the speedo was right on at 65. We had a problem with the upper gears as well and to be honest with you I know we replaced them with a heavier set of gears but I can't remember with what. All I can tell you is we had broken a couple of teeth off of one of the gears.

We had a new motor built after we bent a connecting rod due to water getting into the cylinder. We basically stuck with the same cam and 4 bolt main but we went with better piston's and heads. We took the carb and intake off of the Tempest and were not gettin the rpm's out of the new motor like we had gotten from the Tempest. The Tempest ran up around 5300 but the now we were only able to get around 4900. We noticed that the front two cyliners kept burning up the spark plugs,actually melting the tips of the plugs. We quickly determined that the motor wasn't getting enough fuel. To make a long story short we upgraded the carb from a 625 to a 750 and it seem to do the trick. Actually had to upgrade the prop to a 23 pitch from a 21.

Thanks Jim

[Jerry Eisele]

Thanks for the input