Daniel: Posting the heads became necessary when Stock Car racers like Smokey Unick, were milling them well beyond factory recommendations.. Apparently also because the realighned intake ports on the new "G" heads, resulted in less casting support, which led to problems when raced..   


Paul

"Dots look like cylinder numbers. I would have just written the number instead of all the dots. ------"

Maybe for religious reasons? Maybe the Reverend knows...LOL

"FREE SAMPLE"

Or, maybe the previous owner was numerically illiterate, and could only count using his fingers?
ALSO (re: posts), maybe someone at FoMoCo could see into the future, where Y-blocks would be overhauled many times (unlike with GMs ‘throw-away’ SBC motor), and numerous clean-up head millings would eventually stack up & become an issue with gasket sealing?

6 VOLTS/POS. GRD. NW INDIANA

Someone must have recycled those "throw-away" motors, because, after 66 years, they are just now gradually being replaced by the new "throw-away" engine. Technically speaking, "motors" are powered by electricity.

Sorry for the late reply on dynamic compression ratio, had to dig out the paperwork.  Here are the last two.  303 Y EMC, 346 Y '55 T-bird.  865 Y hp.

JDC

I got it. They're domed pistons. I looked at your specs 3 times before it registered. I guess I better cancel my Jeopardy contestant reservation.

Email sent regarding the matching G heads.
Walt

Hi Walt, I haven’t seen a message come through. If you want to use my email, you can reach me at

mike.emersonmpls@gmail.com

Mike

MplsMike
'56 Parklane
Minneapolis, MN