Myself personally wouldn't spend a penny on ANY Chevy I6 made before the 2002-2009 4.2 (or Atlas) engine. The stovebolt or ANY siamese port head was a lousy design if go fast is what you want. For regular use I love them. If I had to choose an ohv push rod I6 I would use the Ford 240/300 or the thinner block 250. Both have seven main bearings and 12 port heads which are a natural for any kind of port fuel injection and can take a reasonable amount of boost. The Aussies are getting stingier with their 250 12 port crossflow heads but someone is supposed to be making an aluminum one for the 300 Ford. Ones that want to run fast with an inline 6 can just paint the Ford a GM color and put a Chevy decal on the valve cover, then prepare for a lot of tire smoke. Jack Evans out of McKinney Texas has been dead for many years but his 240 Ford I6 dragster was the first to go 200mph and later 250mph in the 1/4 mile---maybe a tad out of reach for the Chevy Stovebolt.
