Word. That is the same thing I was thinking... The 799 heads were installed on the L33 5.3L HO motors. They were essentially the same and the 243 heads---2" intake valve/1.55" exhaust valves and all! Some say the 799 have better torque numbers than the 243s...but the 243s eventually out-flow the 799s at higher rpms... Its all in the casting of the heads. The 799 castings were more of prototype heads for the 243s. I think the only real difference is in the smoothness of the casting in the ports...Originally Posted by nighthawk
If this motor has the original heads on it, then this "5.3L longblock" this guy might be buying is the all aluminum 5.3L. He needs to go check out the casting on the block of that motor. If so, $600 is an AWESOME deal for an L33 motor!!!!!
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