Looking to build a 455, dual plane intake, fairly aggressive cam, 494 stroker (possible), i'd love to run a Q-Jet but even with a Jet or a Cliff's.....will it be enough?
Assuming your 494" engine achieves 100% volumetric efficiency (which is highly unlikely), and your shift points are at 5500rpm, it could make use of 786cfm. A 1971 and later big block Q-Jet will flow about 800cfm, and would be adequate for your application. The typical street / strip engine (10:1 compression, dual plane intake, 225-235 degree intake duration @ 0.050" valve lift) will achieve about 85% volumetric efficiency. In such an application an 800cfm Q-Jet will be plenty to feed your 494 up to 6600rpm (if it will stay together spun that high). Call Cliff Ruggles. He is very knowledgeable about the Q-Jet, and is fully capable of building you a carb that will work for you. Jim J.
