For those of you that want to run a factory 68 340 4-speed cam...
I worked with another member here and we sent one of my cams that was custom ground to be a clone of the 68 340 4-speed cam to Ken Heard at Oregon Cams and they measured it so they can duplicate it and now have it available for sale.
Here are the Oregon Cam specs/details:
221/227 @ .050”, 276/286 adv, .438”/.456” lift, 114 sep
Per the 68 Plymouth service manual, the factory specs are:
276/284 dur, .444"/.453" lift
Int op = 26° BTC
Int cl = 70° ABC
Exh op = 78° BBC
Exh cl = 26° ATC
Intake centerline = 112° ATC
Exhaust centerline = 116 BTC
Lobe separation = 114°
This is the grind we have been using that is supposed to be the cam you are inquiring about. We made this master from a cam that a customer supplied us that was supposed to be the factory Mopar cam. We have made quite a lot of them. We can do a regrind for $79 on your core or make a new one for $179.