hi, i am wanting to change my exhaust on my totally stock 2010 FXDC for a Vance and Hines Double Barrel staggered system. unfortunately i cannot afford to buy the system & a fuelpak/tuner device so if i leave the A/C stock will my bike run ok with this full system on or will it run too lean. if it is ok to do this then i would at some future date add a fuelpak & A/C. otherwise i will just fit slipons & leave it at that. cheers.