in your driveway I would find out at what RPM the slots max out at. that is 32 total with can capped I am assuming? Those "silver" springs may be letting it come in way too fast & 32 total is way too retarded & is hurting you (temp & performance). what eng? (1) post the RPM (2) depending on the ans to (1) we might wanna get some stiffer springs in there. unless those springs are extremely light & even then I'm suspicioning that we might need more octane. I ain't up on whether E10 10% ethanol) helps or exacerbates pinging & (at least here in Nebraska & we grow more corn than anybody) we have a choice & the pump will say if it is E10 or not