340 Six Pack Engine Specs
Hello,
I've been searching online and I can't believe how hard it is to find the factory MOPAR engine build specs for a 340 six pack motor. I even looked in my 1970 Chilton manual and they don't even list it! Does anyone have a factory spec sheet for this motor? I'm looking for specifics as far as compression, cylinder head chamber volume, cam lift, etc. Many thanks!
You're not gonna find a lot, because not much is different spec-wise from a 4bbl. 340. The heads are the same J castings in every respect except they drilled the pushrod
holes further out to allow for max crossection porting if needed, and used the offset adjustable rockers along with that. Same with the Hydraulic cam specs, ditto pistons
& rods, valves & springs 340 H.P. again. I have a couple of Chiltons that list it....for '71 LOL, they do list the cam lift for the 4bbl/6bbl, but I can't say I trust those to be
100% accurate, they differ slightly from what the DC/MP performance books list, which have also been known to include erroneous info. I had/have a 340 H.P. stick here
somewhere, and I'm sure I checked it out like a million years ago, never used it for anything and forgot the numbers it checked at. Good luck over at the registry, and see
what Allpar has in it's smallblock section, haven't cruised that site in a little while.....................