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And speaking of custom valves, Superior Automotive offers custom valves (right) for 5.7 Hemi owners looking for extra flow and power. Fred says, "There are probably 1,000 5.7 owners for every 6.1 out there, and while the 5.7 does have smaller ports, we can make 'em run." The first step is replacing the stock 2.00/1.55-inch valves with the 2.08/1.600-inch combination used in the 6.1. This change alone will deliver a 7-percent flow improvement and can be performed without the expense of changing the valve seats. With maximum porting, the 5.7 head can flow within striking distance of the stock 6.1. Since 6.1 heads are currently on restriction from Chrysler (i.e., only available for warranty claims), lots of 5.7 owners bring their heads to Superior for porting and valve changes. Superior is also developing a 383 stroker kit for the 5.7 that'll be ready as you read this.