Ok guys I need a little help. My son has a pred 90 with a FMF pipe and I just put a new air box on. The Air box fit both an E-ton and a pred 90. It does have a bigger intake on it. After I put the air box on it has no power. I messed with the pilot adjustment. It takes off but boggs down right away. I need your advice do i need to rejet? if so what size? thanks