Olds 455 hi po 1970-1971 cams were described in advertising duration.....328 degree intake exhaust or 286-287 intake exhaust( Nice touch that 1 degree)
What are OEM camshaft numbers measured at0.050? I just want to know how the old cams compare /duration lift compared to the new ones
Thanks
joepenoso

 

Hi Joe

I have a melling cam that is a copy of the 66 - 67 w30 and 68 Hurst Olds with no AC. Specs. in picture below. It is "only" a 308cam

According to the 442 by the #'s the 328cam was used in 68-69 w30 and 70 w30 manual transmission cars. They do not list #'s at .050. The spec. #'s on the 328 must be higher than the 308cam .

Merry Christmas

 

You can probably find the 328 cam numbers somewhere, I think it was in the 240's at .050.
But the difference is the advertised, they were done at 0 lift. Most today are done at .006 although some are done at .004 and others are even done at .008. That's how some of these guys play with the advertised numbers to make a cam seem more or less aggressive.

 

The camshsft 402569 (W-30) @ .050 ranged from .241 to .246 and the lift ranged from .472 to .477. Lobe sep 110. The duration @ .006 was 316

The camshaft 402194 (W-31, Hurst Olds) @ .50 ranged .230 to .233 with lift @ .470 to .472. Lobe sep 113

The above cams did not any advance built in them, and infact I have found the 402194 to be 1 degree retarded. The duration @ .006 was horrible. I think it was 320.

Remember the above cams were production units and did not have be exact, and that is probabley why some cars were faster than others.

The cams were agressive for there day, however, you have a better secection today. I hope these numbers help

 

Thanks for the help..............I now know where the OEM cams fit in the scheme of things
joepenoso