[Big D]

I put around 35,000 miles on my 66 GMC 305 V-6 in college. Like everyone else has said they are torque monsters but definitely not hot rod material.
Around here there are still lots of grain trucks/dump trucks on the road equipped with the V-6.

I remember it not getting the greatest gas mileage, probably around 8 to 10 city, maybe 12 on the highway with a tailwind.

There used to be a local guy that had one running a set of homemade headers and glasspacks. It sounded pretty sweet.