Originally Posted by lg1969
Bowtie, For your application you really need a 650 vacuum secondary. You need torque not RPM to hall all that heavy cargo. 750 is to big to do the job.
a 750 with mechanical secondaries is too big, with vacuum secondaries it really isn't an issue as they only open with enough air flow, and not a second sooner no matter how hard you stomp on the throttle.