Vacuum value form bone-stock 396/402?

[davepl]

My engine builder used a slightly more aggressive cam.

Factory 1970 is 196/196 duration, .398 .398 lift
Factory 1971 is 192/203 duration, .398 .430 (biased towards exhaust I guess)

My cam is 214/218 and .476/.496, with 66 degrees over overlap, intake centerline of 110 and exhaust centerline of 120. A bit more than stock, but still what I'd consider a fairly mild cam (I hope).

While tuning the engine I can't get more than 14-15 inHg of vacuum. That's plenty for power brakes, but I'm wondering how it compares to a factory original truck.

Anyone have an unmolested, original-cam, original-everything 396 or 402 that they can tell me their idle speed and vacuum for?

If the factory setup makes 16-17, I'm fine. If it's making >20, I need to rethink this cam depending on how it drives.