im looking to change pipes and air filter on a 2014 slim do i have go with a differant calibration or will the efi system compensate (the pipes will have the o2's and the cats)

 

If you change pipes and air filter you need to re-calibrate or add a tuner. HD's fixed cals are not the best, so you'd be better off with a tuner like the PowerVision or TTS.

 

Thanks...... I haven't worked with any late harleys and figured it needed a tuner but wasn't sure ....