MP .474 purple cam
Some good clarifications have been made. The amount of duration you gain is negligible with 1.6 rockers over 1.5's. But it still should be taken into consideration even if it's only 2 degrees.
I might also add that not all manufacturers use .006 as the total duration spec. Some use .004 and others use .008 The industry hasn't adopted a standard of total duration specification. That's where alot of confusion comes in when trying to compare cams.
Just for everybody's info Comps total rating is at .006 and Crane is at .004 so you could have 2 identical cams but with different ratings.
I do remember seeing DJVCuda runs a Mopar .474 cam in his 65 cuda and runs 12.40's with it with stock 587 heads and 3:23 gears. He does have a good 3200 stall in it though. I guess sometimes you just get lucky and it works. I would have never guessed that cam would do that even in a lighter early A-body.
I agree with the others that say go with A lunati or Comp XE. They are more modern and have aggressive rates and more lift. I have ran both the 274XE and the Lunati 60404 in my 360. Everything else being equal the Lunati has quite a bit more low end torque and pulls about the same up top. The Lunati is quite a bit more choppy idling. One strange thing about the Lunati though is it gets 2-3 mpg better than the comp did which surprised me since it's more choppy idling.:dontknow: