Simple physics man. take ( rpms) X (displacement )X( throttle opening %) at a given rpm and you get a fuel consumption number. This isnt a real empirical formula, but you know what I mean.
So, of course, a 355 will consume less at 2800 rpms than a 454, all else being equal.
You want a rat that doesnt eat much gas at cruise. Use a 3X2 intake. Otherwise you'll be in the 13-14 range , and that isn't bad. 3X2 will get you 15-18. Non overdrive 3000 rpm numbers.
ACES 3112/Team Chevelle Gold #62
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