did you do anything with your distrib? if not you might have the same issues as before except you're out $900+

As a rough rule of thumb
the most effective way to increase combustion chamber volume to decrease detonation
is to remove from the exhaust valve side.

On the exhaust side
for performance engines
'de-shrouding'
the exhaust valve surroundings
will increase high lift exhaust flow.

If there is a 'bump' around the sparkplug hole
that looks odd to the casual eye
I would not remove any of that bump
until I had thoroughly researched it.
An odd shape around the sparkplug may be either for increasing turbulence
or
for protecting the sparkplug gap initial spark from being 'blown out'

For example
it is worth looking at the bump around the sparkplug hole of the
stock 1992 Magnum,
RT Magnum and
aluminum Viper combustion chambers.

To my eye
there were subtle changes
that may have been refinements
to 'high swirl'
fast burning performance.

It is also worth asking yourself:

as Squish pushes out a
'tidal wave'
or turbulent gas from either side
where will it mostly head toward,
and will it increase or decrease
clockwise or counterclockwise
spin of the gases?

Car is back together and I think mom would be proud ( she passed away in March and she bought me some car parts!). Used the stealth aluminum heads and left the pistons alone (KB237), used a .020 Cometic gasket that gave me .040 quench, Dist is set up with Vacuum advance running on manifold vacuum which give it 30 degrees at idle, mechanical is all in @ 3000 @ 34 degrees, 1.7 rockers on the exhaust, Mcleod diaphragm clutch, new flywheel, aluminum driveshaft, FBO dist recurve and ignition and a ton of little stuff I hope to forget soon. Stock six pack jetting, may go up a size. Final compression was 10.2 with an 85 cc chamber.
The way it runs now is unbelievable, once the tach hits about 2200 the tone of the exhaust begs you too nail it. Slight gas smell at idle but not bad. I have run about 1/2 tank of 93 through it and there is not a hint of detonation and plugs read just right. My only regret is not doing it sooner and giving my mom a ride. Thanks to all.

Paul glad that ended up working out well. Did you have anyone check over the guide/seats/valves or were they left untouched.

New, one head cc'd 80 and the other was 83-4. At the recommendation of my machine shop (Boyd Machine Norman OK)they opened up the throat area just under the seat to just slightly smaller than the ID of the seat and then I blended it all in, aluminum is SO much easier to work than cast iron, I had them done in about 3-4 hours using a dremel and a flapper wheel and finished it off with a scotch brite wheel. They then sunk the valves with a 3 angle valve job to get the 85 cc I was after. They did check all the guides too. You could probably run them as is but by the time you pay for the heads ($900) and another $320 for the valve work its still cheaper than some others and they look really good on a stock appearing engine. In my case I also had to take a LOT of material out for pushrod clearance. I have adjustable rockers with a hyd cam.If I had known then what I know now I would have had the machine shop ream that too about .050. I also had to shim the rocker shafts .060 to make the pushrods work out. Not real sure why that was necessary since theoretically I only dropped the head .017 which is the difference between the .037 Fel Pro and the .020 Cometics but it works.

The shims also improved the geometry, I didn't realize I had to go into such detail. The exhaust rockers are 1.6 my mistake