Engine Combo's

[carpoor]

Skip the 5.3 head swap, they don't flow as good as the 317s on the six liter. If you are trying to raise compression, go with a set of milled 243s or 799 castings. Plus a lot of the 4.8/5.3 heads have the crappy service port, makes them tend to push water past the head gaskets in that area. And the newer heads are prone to cracking under the valve covers. I am pulling the 5.3 out of my tuck due to a mystery coolant loss. It runs great, but I get a low coolant light every 3-4 months. And it is usually down half a gallon. Swapping in the LQ4/4L80E I never put in my Chevelle.