I have an Oldsmobile 455 in a 1976 challenger speed boat. Switching from the car application to a marine application.Do you have to use a exhaust crossover plugs, what happens if you don't? Then I also was wondering, if you can switch j style heads to k style heads? Also is there a torque spec for the intake?

 

yes you can swap heads not sure on the cross over plugs and I think the intake torque is 25flb I would look up on wild about cars on any specs unless its a after market intake

 

There is a torque spec, and also a torque sequence for both the intake and heads.