Marine 273 build

TR - I like the Magnum idea myself. If you want a pair I have them. They're cores and should be pressure checked because they show cracks (were off a running engine), but they're free if you want them and will outflow the 302s by a bit with no work. They are the main reason the Magnum 5.2s are so strong. The early 5 bolt covers bolt right on to them - the extra bolt doesn't get used and get's covered up. You just need the right lifters, pushrods, and the factory rocker set as I pirated these for my use.