LJDB 103 Posted April 10, 2013 hi anyone had any experiance with the 500 holley. do u guys leave the bigger 50cc pump or fit the smaller 30cc pump. the 50cc pump has the brown cam which pumps a shot threw the full throttle range. mine has a rich stutter when u go WOT but cleans up. i tried a few of the 30cc pump cams which only pump at shot till about 50% that fixed the stutter but doesnt pull as hard in the midrange or top. its got 73 mains and 6.5pv. i tried bigger jets with the green 30cc pump cam but still didnt pull the same. im gonna try maybe 70 or 71 jet with the brown 50cc pump cam and see what happens. iv also tried different sized pump nozzles to try clean up the stutter but with little success. Share this post Link to post Share on other sites
thunderbolt 150 Posted April 10, 2013 keep the 50cc pump and the brown cam tune it with the nozzels i closed down the PV restrictions a bit and run a 7.5 - 8.5 PV the shutter you say is rich sounds more like lean stumble off idle Share this post Link to post Share on other sites