RTK,

If the majority of the cooling air is from forward motion, then the majority of the air has no twist and a simple scoop on the top of both cylinder pairs which curves around the back of the final cylinder will force air down between the cylinders and around the back of the hind cylinder.

However, if the majority of the cooling air is due to prop wash, then the air has a sever twist to it and the scoops need to be alternated to catch the twisting air off the prop. The scoop on the left cylinder pair needs to be on top and the right cylinder pair needs the scoop on the bottom of the cylinders.

The engine will have no cowl and will be working hard pulling nets with a lot of prop slipping. Radar speed is 56 mph with nets deployed. Engine rpm is in the high 6Ks with a 10 pitch prop.

This past year, we used the alternating scoop idea on 150 and 200 twins with no heating problems. We have a 212 - 4 cylinder on the shelf which will also get used this summer and the cooling is more critical on a 4 cylinder than a twin. That is the reason for the posting of the question.

Elson