My puch free spirit was doing nice with a proma gp, bing 14 (72 jet) and a high comp cylinder head - i was doing around 32-34ish with a slow low end...well, i ordered a bing 15 (82 jet) w/intake and now it bogs/chokes at 27ish...i tried even with out my high flow filter same thing. I haven't messed with jets just yet, does it sound like i need to go down in jets in the new carb? or should I slap the 14 back on? I thought the bing 15 would give me more air allowing a better low end.