2002 GT 40 Long Block

compskier wrote: I'm looking to put a long block GT 40 engine in my 2002 Ski Nautique and have 2 questions: 1. I'm getting conflicting info on the engine rotation. One says that it requires a reverse rotation engine and another source says standard rotation since it has the 1.23/1 transmission. Both are people that are knowledgeable on Correct Crafts and I respect their experience, but I don't know which way to go. How do I get a definitive answer? 2. I've been told that if the engine has been rebuilt, it can't be bored more than 20 thousands (0.020) or the computer will run the engine too lean. Is this correct? Thanks for any insight, first time posting on this forum. Ed

Your definitive answer would be the ID tag attached to the intake manifold if it's still there or you could look at your firing order as another check (looking at the distributor a normal rotation is 1 3 7 2 6 5 4 8 going counterclockwise) reverse would be 1 8 4 5 6 2 7 3 also going counterclockwise) or you could listen to the second answer somebody gave you about it being normal rotation since it's a CC and it's hooked to a 1.23 to 1 transmission

As far as the second question, I seem to remember hearing something like this, but can,t imagine it's tuned that close to the ragged edge as a stock engine and that the 0.020 or a 0.030 or 0.040 overbore would really matter...................but don't believe me on that, wait for more answers.

This might be what me and Gary are remembering. It's from Planet Nautique

PN thread about overbore

Fair amount of conflicting info between posts so no definitive answer there.

I'd talk to Jody Seal at Florida Inboards I think and see what he says

Florida Inboards

After reading it a few times it sounds like bad sensors caused his problem after the rebuild and once they were replaced the ECM handled his 0.040 overbore with no problem.

Compskier you need to find more knowledgable group because the GT-40 is a lefty only.

Where in FL are you?

Yes on over bore. It's been a while but I was in the same boat with cracked block . I called pcm if I rembered correctly they said not to go over xxx because the ecu could not compensate .