I am a SP2P fan ... and in direct reference to the topic at hand .. there is no better intake for mpg and throttle-response on a stocker-type motor.

To label this intake an "emissions" piece is not really correct .. it is emissions "legal". And YES .. the ports are very small ...to get the best A/F velocity ... for the best atomization. Because of these small ports .. the intake is "dead" over 4200 rpms or so.

IN CASE anyone is interested ... a pic is attached that shows the diff between a stock size B/RB port and a RB SP2P intake.

When I get the rear-end gear changed to a 3.73 in my motorhome .. I will be putting one of these on the 413. Presently I am running a Streetmaster intake. GOOD piece .. but for higher rpm usage(with the 4.56 gear now).