Flathead Camshaft ID?

[F1 Flathead]

Looking for some help identifying the cam in my 40 Merc Flathead. The original ower said it was a "3/4 Race" cam bought in Detroit in the 70's. The snout is labled "Dunn" and "Detroit" and stamped "F" in two places. Does anyone recognize it? How 'bout 'Ol Ron? I checked the lift and it measures about .320" like an Isky 88 .
Thanks,
Dan

 

[Ol' Ron]

OOOHHH Yes! the Dunn "W" was one of the best track cams of the era. No telling what a "3/4" would be like.

 

[F1 Flathead]

Thanks Ron. So you've not heard of a Dunn "F"? I have it out of the engine now so I could do a better check of the lift. Never tried measuring duration. I'll have to do some reading on how to do that. It sure does run nice. Seems to make good power but idles nicely.
Dan