049s are a MkIV head and will not work on a GenV block. There will be a mismatch in the cooling passages at the lifter valley side of the deck.Does anyone know what heads came on a 08/92 production 7.4 Carb, 300hp. Bravo1 ? Mercruiser said Oval Port but couldn't say which ones. Should they be "peanut ports" or larger Oval. I would like to switch out to 049's. Will this Gen V support or is the compression going to be a problem?
Click the link, go to the Big Block Chevy section and scroll all the way to the bottom and it will show you the difference between the cooling passages between a MkIV and a GenV.
I think I remember hearing about a company that might make a special head gasket that will adapt a set of MkIV heads to a GenV block, but the experts may wanna chime in on that one.