That engine is super solid all the way through. Id be willing to bet that the head is nearly a hundred pounds on its own. You'll have to get creative and then come in right under the limit. Maybe a dry sump crankcase for starters. There's gonna be several tabs, bosses, and the like that can come off but then your engine is dedicated to that tractor. You'll probably be better off switching to a lighter engine. Which is a shame considering the power you can get out of a 4BT...
how big are these tractors??? this sounds like it could be interesting. The 4bt is capable of the 200hp/380tq neighborhood pretty readily. You just have to slide/replace the plate. Power definitely wont be a problem for you.
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