AMC 360 head questions

Hey guys I have some questions for you I know you can answer. These are pertaining questions concerning a AMC 360 heads.

I have only come across one AMC block that had a couple head bolts go into water, and one that had a single bolt go into water. They're supposed to be blind holes.   Always check though. The outer bolt hole area on AMC heads was machined with a aquare end mill.   This is a stress riser, doesn't matter who the manufacturer is. Even with proper torque procedure, the ends may be weakened from years of heat cycling. They're kind of hanging out in space with no support and no radius machined that would help distribute load. Those bolts should be last in the torque sequence no matter which way you start.

As far as the gasket goes, the danger range on quench is approx. .060-.080, depending on chamber and piston design. .055 quench will run fine. .090 will run fine. The difference with tight quench, is you get better mixture motion in the chamber if you have a flat piston top under the quench pad.   A dished piston top under the quench pad is going to do very little with tight quench, as there will only be a small portion of the piston under the pad. It will help a little, but nothing like running a D-dish piston with the flat area under the quench pad. Tight quench is good for power, but only with the right parts. You're trying to move the mixture towards the spark plug, and a dished piston won't do that.

tyrodtom wrote:   The early TSMs say the second bolt from the bottom front, left side goes into the water jacket,  and should be sealed.   But some later TSMs don't mention it.  I've got  4 360 blocks setting around,  and one in my 82 J-10 .   Of the blocks I have setting around,  one, out of a 70 Ambassador,  and the one I have in My J-10, from a 75 Matador,  that one bolt hole is open to the water jacket.  On the other 3 the hole is blind.

Maybe it's a difference between early and late blocks then. I didn't check casting dates on the blocks that had a hole open to water.   Wonder if it was a running change.

tyrodtom wrote:   The early TSMs say the second bolt from the bottom front, left side goes into the water jacket,  and should be sealed.   But some later TSMs don't mention it.  I've got  4 360 blocks setting around,  and one in my 82 J-10 .   Of the blocks I have setting around,  one, out of a 70 Ambassador,  and the one I have in My J-10, from a 75 Matador,  that one bolt hole is open to the water jacket.  On the other 3 the hole is blind.

When you say "left side" are you referring to the passenger's side? Just wanting to make sure. That info is interesting, thank you!😃

I've seen that in the manuals, and never seen it in real life. They obviously designed it to have blind bosses, my guess is very early production they had some kind of a mistake or quality problem resulting in an open boss, which they subsequently fixed. I imagine the problem only existed in early production.