I built a 360 many years ago that is in my 4x4.It has flattop w/valve reliefs,zero decked.70cc heads.Iron.Is there a head that has the same chamber size,or close that is closed so I can get good quench?I run 91 octane and have to back my timing off to reduce the ping.Comp cam 268,installed straight up.I would like a bit more grunt to.High gears and 35 in. tall tires.At cruise speeds and with a load if you put your foot in it it will start to ping.

The only closed chamber 340/360 heads are going to be Magnums or Eddies; both of which are 63cc chamber size. What is your compression ratio right now?

There are stock Mopar closed chamber small block heads.

or Indy X heads...LA rockers and intake bolts..with Magnum chambers..

If memory serves,9.2.What are the swirl chamber heads,302/308 castings?Low 60's like the others?Without loosing low end torque,are some of these aftermarket heads overkill for a 4x4?Then the next question is ,if they will work,is there enough material in the chamber to get the cc's close to the 70 that I am now?

The 308's are open chambered so they'd be more than 60 ish CC's but they are the best OE open chambered iron heads but they'd be no quench. I'd think you get some 302's into the 70's & iirc they are 1.78" intakes & 1.88's with some good porting is a good plan for 302's. I have a set just ain't done anything with them yet

http://www.moparts.org/Tech/Archive/smallblock/23.html

Note: This discussion does not include Magnum heads:

308 chambers as found on an engine will run 68 - 72cc, maybe even more. They will look the same as any other 360 head.

Only 273s and 318s came with closed chamber heads. The majority of 318 heads are open chamber.

The 302s are not for serious power. Sure, Dulcich got mega power out of them, but what you may not know about his "super ported" 302s is that shortly after he began to use them, one of the ports developed a crack and now he is not recommending them for performance, at least that's what I took from a private post.

The 308s had such a good exhaust port that the stock camshaft for the 360s that used them had more intake duration than exhaust. It's usually the other way around.

There is no way to get squish in a 360 chamber without either using step head (quench dome) pistons or welding up the head to create a squish pad.

There is no Mopar LA closed chamber head that is even close to 70cc.

R.