I'm running a 4to1 Kerker without baffle......just the end cone but I have K&N pods. I'm in California at 89 ft. elevation. I can't remember if I have 120 or 125 mains (I have both) but I know my needles are OEM and clipped at 2nd from top (one step lean from the middle).It goes smooth from idle on up....no hiccups. You should probably see what clip setting you're at and show a picture of your needle (close up). I'm not sure about markings but I do know aftermarkets have different tapers. Its hard to tell what has been changed out in 40 years time if you aren't the original owner. Should be able to see a stamped # on the mains though. Lots of different combinations out there at different elevations so the more info you provide the better. So far you have Kerker, stock K&N, 836 kit, running at 100 ft.