Stop wondering/guessing and find out ! I must suggest this book,"Engine Airflow" #HP1537 by HP Books. NO AFFILIATION. Concise, in depth and comprehensible, a good combination. For instance, this book and many skilled engine builders suggest, measuring cylinder head airflows including inlet maifolds, carbs or throttle bodies as a good first building step to designining a successfull build. Did you know that 200 cfm @ 28" H20 of inlet airflow, on gasolene, 8 cylinders should make in excess of 400hp., if other spec's are optimized ? Onward, roverman.