[6T5 Cat]

1964 GTO:
389 4 brl 325 h.p.
389 3x2 348 h.p.

1964 Big Car:
389 4 brl 306 h.p.
421 4 brl 320 h.p.
421 3x2 350 h.p.

duration 273/289 lift .407/.410 C/L 113 Overlap 54

[63gpstanley]

Were they fitted in anything older? I found one in a 347 I got with my car.

Dave.

[6T5 Cat]

Yes, they'll fit all the way back to 1955. the @ .050 dur specs are 197/212.

[6T5 Cat]

Dave, the stock 57 cam is actually pretty close to the same specs.

[63gpstanley]

The 347 was a bit of a mix of parts anyway, it had 670 heads and a matching '67 intake, a vac. sec 650 Holley etc. It supposedly went reasonably well for a little motor.

Dave

[6T5 Cat]

Dave, I don't think I answered your question correctly, so I'll give it another shot. Pontiac didn't come out with the 524009 cam untill 1964. However, Pontiac used the same cam in 1965 but re-numbered it to 9779067. They were identical in specs.

Pontiac used 3 factory cams in 1957.
The 519640 was used in the 8.5 compression engines with 2 brl carbs, 227 h.p., and the 4 brl engine with 244 h.p. The 529472 cam was used in the high compression, 10:0 engines with 2 brl, 252 h.p., 4 brl, 270 h.p., and the 3x2 290 h.p. engines. Cam 524886 was used in the 317 h.p. fuel injection engine. Customer could also buy an Isky E-2 cam & kit over the counter and have it dealer installed.

Specs for the 524472 cams: duration 273/282 advertized, 200/209 @ .050. C/L 106/116, lift .407/.411, overlap 55

Pontiac used the 519640 from 55 to 1964, the 529472 was used from 56 to 64, and the 524886 was used from 56 to 62.

Hope this answers your question. Bob