low-end with large cylinder heads on a small engine, and went on to tell us about the opposite side of the equation. "The same goes for an engine that has large cubic inches and small cylinder heads. The engine would have tons of torque but run out of power on the top-end. You can only pump so much air through a small head. It would be the same as trying to pour five gallons of water into a one-gallon bucket." That was exactly what was happening with our test engine,the intake runners were too small given its 331ci size and the supercharger huffing in more air.
Molylube was applied to the studs and washers before the heads were torqued down. It is always recommended to use some type of lube, like engine assembly lube, on the studs as it is required for the proper torque sequence.
Holiday torqued the heads down to 105 Ib-ft with moly lube. The high torque rating was due to the Vi-inch studs. He started with just 40 Ib-ft and began in the center and worked his way to the outer ones. Holiday then hit each with 70 Ib-ft of torque using the same inside/outside technique. The final go around was done to 105 Ib-ft.
The exhaust ports not only feature CNC porting, but also a multitude of header bolt holes for a variety of header styles.
Holiday slides the heads on to the Boss short-block.
The intake ports were CNC-ported by Keith Craft Racing Engines, and have 210cc intake runner ports and flow 317 cfm at 0.600-inch lift.
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