michigan 29r
New Member
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