Stop in for a cup of coffee

George Jets said

Here are the Mopar Specs for the 340 camshafts.

The 444/276 cam is available through Jegs Mopar Performance Camshafts.

The 453/284 4 speed 340 cam could be cut by Oregon Cams, don't think that one is available in mass supply.

View attachment 1715410509

Click to expand...

Here's the information that we have from our "research"... My degree info has some error as my degree wheel may not have been accurately centered as the hole in the wheel is larger than the bolt and I did my best to eyeball it... I now have a bushing to center it more accurately for future checks...


68 340 4 speed cam from service manual:

Intake op: 26° BTC
Intake cl: 70° ABC
Exhaust op: 78° BBC
Exhaust cl: 26° ATC
Overlap: 52°

Intake duration: 276°
Exhaust duration: 284°
Intake lift: .444"
Exhaust lift: .453"

Calculated from valve open/close specs:
Intake duration: 276°
Exhaust duration: 284°
Intake Cl: 112° ATC
Exhaust Cl: 116° BTC
Lobe Center: 114°


68 340 Auto cam from service manual:

Intake op: 22° BTC
Intake cl: 66° ABC
Exhaust op: 74° BBC
Exhaust cl: 22° ATC
Overlap: 44°


Intake duration: 268°
Exhaust duration: 276°
Intake lift: .429"
Exhaust lift: .444"

Calculated from valve open/close specs:

Intake duration: 268°
Exhaust duration: 276°
Intake Cl: 112° ATC
Exhaust Cl: 116° BTC
Lobe Center: 114°

My custom ground 340 Auto Cam layout from Ken Hoard Oregon Cams:



My custom ground 340 4 Speed Cam layout from Ken Hoard Oregon Cams:



Oregon cam data vs my degree check:



340 4 speed data from Service manual: