Originally Posted By NachoRT74
Originally Posted By BSB67


The lift is not that different, like 0.020" more. I have the numbers, just to lazy to go get them. The duration is bigger as well, and the real reason for the performance increase.

None of the "purple shafts" were installed by the factory. The original purples shaft/shafts were a step up or more from what was installed from the factory in wedge motors. I guess now you can purchase a resto cam from MP. Maybe it is called a purple cam too.



Damn! sometimes I forgett I have the direct conection performance book!!

Actually my 74 Mopar parts catalog matches the number posted there for the HiPo camshaft, 3512907 camshaft... used on all 383/400 HP and 440 HP, but this means the 335 383 or 330 383 ? so the 330 383 is not an HP still being a magnum ?

then there is a superseded number for it, 4071002 camshaft one of them I have it NOS on its original box, and is purple.

then read it better on some other section and the 335 383 camshaft takes the stock 3512907... which by the direct conection book is 268-284 camsshaft with 450 lift... that meets the MP 4452783 spec and the fact the higher camshaft used from factory is a purple one



If you are talking "original" purple shaft, I think your dot connecting might be flawed.

What Direct Connection and Mopar Performance called "Purple Shafts" back in the 1970s started with the "Hemi Grind", I believe, followed by the 484 and 292, previously Racer Brown SSH-25 and -44 respectively. As years went by, the family of "purple shaft" grew and at some point added the replacement cam you have. I don't recall anyone in the 1970s or 1980 calling the factory cam a "purple cam", or running out to by one.

Could be mistaken.