34mm VW carb on a generac

I'm trying to get my boat on the water again. I fixed the cage and replaced the motor. On this motor I am using a 34mm bocar carb which is a solex clone from a VW motor. I'm also going to run this motor without the shroud or the cooling fan I hope the prop will pull enough air past the motor to keep it cool. Has anyone else ran a v-twin without the shroud on an airboat without it overheating? We all do it with the 0-84 and it stays cool and I used to run my Honda's this way because removing the cooling fan I would gain about 100rpm. Between the carb and removing the fan I'm hoping to get some more rpms out of this motor. Later I will remove the heads from my broken motor shave and port them then swap them out.

Just curious...On the generac engines...The cooling fan is just that, a cooling fan ??? In other words it's not some type of a counterweight to keep the parts balanced ?? I know some small engines use that front cooling fan as a harmonic balancer also...Does it appear to have any balancing weights/holes in it ???

No it's just a big plastic fan that bolts to the flywheel. It don't weigh but a few ounces and it don't have any sign of being balanced. I have two they both look the same. I'm worried about the heads getting to hot without it. I did find another motor for sale for cheap if I can get it just in case it does get to hot

Off subject but didn't want to start a new thread just for this. I needed a spacer between my prop and hub I have a steel plate I used before but I want to keep it light this time. I would really like an aluminum spacer but can't afford one right now. So I made one out of 3/4" pressure treated plywood I'm going to seal it also. Does anyone think this is a bad idea to use plywood?

How thick is that i may have something that will work this is 2 in thick . i know you know what it is.

Mine is only .75" I think that's the same bolt pattern as the steel adapter I was using for a spacer. I have an aluminum adapter like that but it's for a continental GPU to reg prop. And it's kinda heavy I'm trying to keep it light this time. it looks like yours will go from rotax to a regular Airboat prop getting the prop out 2" would help a bunch. my other problem is I am out of money at the moment. Im waiting for my taxes just to buy a prop

its for a v6 chevy and bolt pattern is lxl. the small pattern is for chevy crankshaft. the small bolt pattern is 3 in and the large is 4.6

My prop showed up today I used 2 face plates for a spacer and cut it down to 55" and 12 deg pitch and it turned 2590rpm without the cooling fan and 2440 with it. The response is incredible. My old 084 with 28mm solex carb had a 53" 12deg it turned 2800rpm and had very sluggish throttle response. I've read that cutting 1" off will gain about 100rpm that would make it the same as the 0-84 right now with better response and lighter. Hopefully it will hold together as long as one.