I just changed head gaskets and had the heads ported as I was getting pressure in coolant and overheating. Turns out a piece of head gasket went out and was leaking.

Anyway I had the heads pressure tested for cracks and Vaccum tested for leaky valves turns out all ok.

I install them back to the car and car doesn't ovwrheat anymore and coolant flows nicely. However I'm trying to get the idle perfect and I cant. I always had an issue with the idle. I purchased a vacuum guage from here but it's in bar and reads .0 to .8. The needle bounces rapidly back and forth from .6 to .7 which is 17.5 to 20.5 inches Hg.

I played with the timing and it seems to run best at around 16-17 degrees on the balancer.

There is a mid range cam installed, it's a 302 with edelbrock 600 carb, slightly higher aluminum intake manifold, it's been bored over once and has Patriot long tube headers.

Not sure what else I can test or try out. Any ideas guys?