I have a 95 mustang gt 5.0 with stock bottom end, gt40p heads 1.6 roller rockers, comp xe264hr cam, 75mm throttle body, 30 lb injectors, MAF calibrated for the injectors, BBK cold air intake, Trick flow upper and lower, pacesetter long tube headers, custom 3” exhaust, no o2s (yet, bought without them), adj. FPR, around 38 psi. I’ve checked for vacuum leaks, done voltage drops, etc.. , the car will idle fine for a minute or so, surge to 3-4K rpm then drop down and idle and this will continue. Is there anyone else that has ever gone through this exact problem before? I’m new to the site and have been scouring the forums but can’t find a problem similar to mine. I also have done the surging idle checklist. Any help would be greatly appreciated! Also I forgot to add I have an underdrive pulley and the alternator is on the way out I believe because while running battery voltage (optima less than 1 year old) doesn’t go above 12.7 mark at idle.