I will be installing a near freshly rebuilt stock 225 in my brother's 74 Duster in the near future. Before it goes into the car, I plan on doing a number of modifications to it, including swapping to a hydraulic camshaft and installing a head I had rebuilt and milled a few years ago.

I have the option of a used stock 81-87 hydraulic cam OR using a NOS purple shaft hydraulic cam p4529340.

Doctor Dodge gives the specs for the purple shaft cam as follows:
I have been searching for a profile for the stock hydraulic cam but can't find one. Anybody have one handy?

The car is a 74 Duster with a lockup 904, 3.2 sure grip rear axle, full interior, basically all stock. I am also hoping to install a head the has been milled .100 to have combustion chambers in the low 40cc range (don't recall specs offhand, been a few years since I measured them).

For this application, which cam would you guys recommend? Stock hydraulic or purple shaft hydraulic?

Thanks.

Purple. The stock '81 cam looks like this:

228° intake duration, 228° exhaust duration, 18° overlap, 0.2523" lift at cam, 0.378" lift at valve.

Intake opens: 6° BTDC
Intake closes: 42° ABDC

Exhaust opens:36° BBDC
Exhaust closes: 12° ATDC

Centreline: 108°

In other words: a very meek camshaft that reminds us of the '60-'64 mechanical cam (232° intake, 228° exhaust, 8° overlap, and I think it was ~0.365" lift).

I interpret Doc's description as meaning the P4529340 cam is similar in specification to a stock '71-'80 mechanical cam, but for the hydraulic valvetrain setup. If I'm wrong I hope he'll correct me on that.

(And now that I've found those two different lift specs in the '81 callout, it's occurring to me that the lift figures we commonly throw around, like 0.436" for the MP 244 solid cam, are @valve, not @cam, so the '60-'64 cam would have 0.2433" lift @cam, again similar to the '81-'87 stock hydraulic item)

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Intersting, thanks again Dan!

Fingers crossed I will be doing this swap before the first quarter of next year is done....