I am considering a Formula 353 with 600SCI's that have been upgraded to Whipple Stage 2. I am curious to the reliability of the 600SCI's? What can I expect as for the durability and reliability from these motors. I understand it will have alot to do with how they have been operated and maintained. When could I normally expect to have to address the upper drivetrain? Any and all "Real Life" experiences will be appreciated.

My buddy had a 38ZR with the Whipple upgrade. Was happy. Biggest thing is having the right drives with 600s.....since they came with XRs which were marginal at best with that power.

If the boat doesn't have SCX I would plan on an additional 40k to have reliable boating.

I wouldn't be scared of a boat with upgraded 600s. In reality any boat with 500+hp, especially larger and faster boats require more money to Maintain, a lot more. Speed cost money!

The drives are a major weak link with 600+ HP. Either upgrade to complete SCX or Arneson. Or plan on rebuilding drives every season or two.

What year boat/motors? Some of the earlier and even later 525's 600's 700's had rocker arm problems with the crane Golds, and it really didnt matter how they were driven for no reason it seems some of those motors go through the crane rocker arms. If I was getting the boat that would be something to look at. Check out the bearings on the rocker arms before closing the deal. As far as stage 2 kits with good valvetrain it shouldnt affect the motors much. Drives probably will need some updates.

I have had the Whipple stage 2 upgrade for 5 years and a little over 100 hours with no issues at all just have to run 91 octane instead of 87.

Boat and Motors are 2006.

Thanks for all the advice and input.