Got a few more questions about this engine. It has a two barrel carburetor. Is this the same carburetor as on the 304? It sure looks like the same thing but it must have larger jetting and ? The block looks good, has a slight ridge, and lots of sludge buildup. There was quite a bit of sludge crap under the intake manifold. The heads have a lot of carbon on them, must have been running very rich or moving some oil through the valve guide seals I would guess. The cylinder walls seem OK. The top of the pistons are carboned up, would this follow with bad guide seals? The cylinders have very little ridge on them so I don't think it was a bad ring. I remember when I first bought my 70 Javelin it burned a quart every 300 miles until I took it back to the dealer and they put guide seals in it then it stopped using oil. I watched them install the seals. They had a fitting that connected the shop air to a spark plug hole and they used this to keep the valve shut while they used a tool to lever the spring compressed enough to remove the keepers. What might the combustion chamber look like if a head were cracked and leaking coolant into the chamber? thanks, Armand