The RA4 cam was the first one that Pontiac engineering design with the aid of a computer, in fact I have heard that it was the first such cam done that way in the whole of GM.
Of the many differences it has over the 744 cam is another 11 degrees of overlap which took it up to 87 degrees of overlap .
This is not a pansy ass overlap amount for a production vehicle!
This is a full 24 degrees more overlap then the 068 cam , so this is a huge difference and is the main reason why 3.90 rear gears where mandatory with the RA4 motor and on top of that you could not order AC in a car with the RA4 motor option.
It’s quite a beast in a 400 cid motor with out 3.90 gears and Rhoads lifters and less then a true 10.5 compression.
A blueprinted RA4 motor with 11.5 comp or greater is still a impressive runner on the 1/4 mile even today .
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I do stuff for reasons.
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