engine won't run with sbp air filter

I purchased a slim line filter from sbp for my grubee gt-5. I have ported the intake and exhaust, installed an xchamber and upgraded plug and wire. The problem I have is when the new filter is on, my mid range is non exsistant and it will only accelerate when going down hill. if I restrict the air flow it gets better, but the stock p.o.s filter is the only way it runs right. Has anyone had this problem and can I correct it by restricting the new filter more

it runs great on the top end and plug is golden brown, but with the sbp filter its a chore to get it there. bolt the old one on and its fine. ever heard of too much air?

yes, at wot golden brown. at idle golden brown. when engine is bogging, black and wet. tried all 5 needle seats, but 2nd from top is where it likes the old filter