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phragle
03-07-2010, 02:58 AM
Workin with my nephew on his boat, 76' 26 foot betram moppie. Has twin 6 cylinders with alphas. The 6's are wasted, need new heads. He has it in his head he wants to convert to 350's. Looking in the bildge, I am going to have to move stringers as the 6's have a mount on the nose. The gimbles also need tightening up. I think (imho) that for what he uses it for (running around the local islands, occasionale trip to put-in-bay) that just fresahening everything up will give him all he wants and then some. How much would really be gained after all the work to drop in 350's ?? Cost wise after tightening the gimbles, redoing the stringers, reproping etc? it's a 35~40 mph boat now, Im thinking on a good day with the 350's he might see 50..and the fuel consumption change would be negligable.....

Buoy
03-07-2010, 03:07 AM
Workin with my nephew on his boat, 76' 26 foot betram moppie. Has twin 6 cylinders with alphas. The 6's are wasted, need new heads. He has it in his head he wants to convert to 350's. Looking in the bildge, I am going to have to move stringers as the 6's have a mount on the nose. The gimbles also need tightening up. I think (imho) that for what he uses it for (running around the local islands, occasionale trip to put-in-bay) that just fresahening everything up will give him all he wants and then some. How much would really be gained after all the work to drop in 350's ?? Cost wise after tightening the gimbles, redoing the stringers, reproping etc? it's a 35~40 mph boat now, Im thinking on a good day with the 350's he might see 50..and the fuel consumption change would be negligable.....

He already has the 6-cyls, I wouldn't bother with the repower, and all the work involved. Why cut it up??
Leave it alone, and just go through what you already have.
It's never gonna win the LOTO shootout, so just make a good reliable boat.
A boat that starts everytime, and get's you home everytime, and that you have fun on is worth more to me than a boat that does 180 on a pass.

phragle
03-07-2010, 04:19 AM
Thats what I was trying to tell him... turn the key, go for a boat ride....

Scarab KV
03-07-2010, 09:12 AM
Keep it simple.

sector
03-07-2010, 10:16 AM
If you can find them the 292 truck engines work well. Everything bolts right up but they're just a little taller. I built one for a friend years ago to put in a really nice older Searay that had the 250 six. He wanted a little more power but didn't want to hack up the engine cover. Used some sort of Crane cam that I can't remember the number of and a spread bore Holly that bolted right on the original manifold. Didn't have the power of a small block and cost more to build but had lots of torque and was worth the effort.

Ratickle
03-07-2010, 10:22 AM
I'd go with the rebuilt 6's and bolt them in. Alpha's are also cheap to replace. If I were to redo that boat with mosr power, I'd PM Charlie and Brownie to see what the race setup would have been and go with whatever that was then. Can't see ruining a Moppie to make it modern when a repower to the day and age they were raced would be much cooler....