I am having my BBC motor rebuilt and they are putting roller rockers in. My question is has anyone had issues with stock Mercuruiser exhaust hitting taller valve covers. Or what covers will work I assume my short factory covers will not work. Any help would be great.

If the engine is a Gen VI, then you can grind off the little tabs under the covers and they should fit. There are several aftermarket ones that you can use. Hardin Marine has some nice 2 piece covers, IMCO and Eddie Marine both have cast alum covers that will clear your exhaust.
Eddie

Thanks for the quick reply. It is a Gen 4 what is the difference?

The stock valve covers should clear the roller rockers. I know for sure they will clear on Gen V's and VI's if you grind off the drip tabs. The IV's used different valve covers, but most likely they will still clear.

Thanks Griff!!