will check compression tomorrow. I'll post then! Thanks.

Scan-tool doesn't show individual, which would be nice, I would be able to tell if a single cylinder is REALLY the problem, and just screwing up fuel trim enough to make the rest misfire.

At this point, I am going to forget about the fact that iut runs fine at any speed other than idle, because you guys seem to be ignoring it, and it may make us overlook something important. It would be crazy if a bad injector caused this. However, what if it is?!? I like to be completely objective in everything I do, so this makes sense to go down this path with this frame of reference.

Also thinking of biting the bullet and buying this: http://www.autel.us/pdf/MaxiSYS_Comparison.pdf

If it was a bad injector, hence we would see a P030? and not a P0300.

Sorry, but when it comes to a 300, its one of the most difficult P-codes to diagnose. And it get'* really difficult because you had the whole top half off. So there is no telling if you left a vac line off or goofed a gasket or who knows.

as far as the single misfire code, a single wont always set the single code,sometimes the random because other cylinders are affected. the other way seems you can trust if it says it cyl whatever its definitely going to be something with that one.

That is why having a scanner with a missfire bar graph comes in handy. It will show the cylinder with the most missfires giving you a direction to go.

Alright, compression test went bad. Cyl 6 is 10. All others are 180-200.

First thing is that I need to see if the valves are floating due to the .020" head milling. Will pull valve covers and relieve pressure and re-check.

valves are floating very happy about this.

I will fix, autozone carries the shims. Odd that the machine shop can get them, lol!

I will update when I get it fixed and if it is fixed COMPLETELY!

I thought I saw rocker shims or rocker spacers on the autozone website, yet I cannot find them ANYWHERE. Anyone have a source I can get these from?

I remember when I asked for a head spacer, the guy who milled my heads said they don't make any for this engine. He said they make rocker arm spacers, but he also said to put it together and if you have problems, THEN shim the arms. Otherwise, it is going to be fine.

Well, this was Schmidts automotive in Indy. One of the last engine machine shops around. I remember asking the parts department a while back for a price on the spacers, they said they can't get them. SO now I'm stock... I really don't want to make my own spacers, but unless I can get a source, I may have to!

never heard of the spacers, but on a sbc if you make a bunch of changes to heads/cam/lifters/whatever you get custom pushrods from summit or something. so i would measure yours and see if they have shorter ones

If he only removed .020 from the heads, why did it only effect #6 and not the rest of them?

I know that my post is hind sight and may not be useful at this point. I have been down this road quite a few times. Most the time when I get misfires at idle that clear up when on the throttle I find that my problem is in the valve train. I know this is a tough one at times- cause the p0300 is such a general DTC. It can lead you and many different directions. I would say that .020 is way too much on these particular heads. It seems very little but it is just enough to change the geometry of the valve train components. GM Service specs for Cylinder head cleaning and inspection instructs you to replace the head if you have to mill more then .010! It sounds like you did a very thorough job on the car and I am certain that you are going to make your customer happy. I am sure that there are ways you can work around this- but if it were me i'd just replace the heads at this point. =D Good luck and hope that you Git-R-Done.

Aaron