Should I Re-power my 18 Classic?

[Riley]

Hey guys, Spring is in the air and it should only be a couple of weeks before the Donzi comes out of storage. I'm still faced with the question of re-powering, and I'd appreciate some input. I've got a 1999 18' Classic powered with the Merc 5.0 with a 2bbl. It's a fantastic boat, really economical, but I'd like a bit more top end. Here are my questions: 1. Is there any reason not to re-power? 2. I'm leaning heavily towards a GM 350 crate motor with the Vortech heads. Any thoughts on this powerplant? Thanks for your input....Chris.

[riverrat]

Riley, man that's a lot of money to spend on a new boat..I've got a '99 with the 350 mag ang I'm very happy with it. It runs about 68
(speedo) & does it fast. I think if I were you I'd look into a procharger& differant exhaust for the motor you have. You won't get anything for the motor when you pull it anyway, so why not add some hop up to it & get your moneys worth. as for a crate motor I would stay with a merccruiser motor they are built to withstand the constant rpm and abuse we put on them in the water. My mag is a roller cam motor & runs on plus gas. My motor building buddy feels that it will last forever. (just my opinion) how fast is your setup? what prop are you running? http://www.donzi.net/ubb/biggrin.gif http://www.donzi.net/ubb/biggrin.gif http://www.donzi.net/ubb/biggrin.gif

[Blewbyu]

Riley-I have the 5.7 H.O.ZZZ crate motor in my X-18,alum heads/roller cam/pink rods/steel crank etc.The motor has nearly 400 hrs on it now,almost all at WOT or close.Still strong as new,lights on first crank,and runs fast.385 HP-runs approx 73 mph w/Spinelli lab finished 22" prop behind Volvo 290.HEI ignition is superdependable.You can't scatter this motor!I'm a big fan of these motors,and strongly recommend them for the marine application.Must be FWC if you run in salt.

[Greg Riach]

Riley

I have a ZZ3 crate motor in my 1978 18. I have had no problems, its strong, reliable and does what I want. I run in fresh water so the aluminium heads & manifold are no problem for me. I am more than happy with mine.


Greg