Topic: Guessing I need to resurface??

[Reganator]

I'd be interested to see if it works out.

I'd be inclined to think it would be fine, but I can understand your apprehension in running an experiment. 

I'd also point out that the Mercedes head in that video is a tad different.  It's a bit more complicated with the cooling jackets and all, and they were in part resurfacing to remove a warped area of the head, which is more about making it level than smooth, but I'm sure they were going for both.

Compare that to your head up top with those big meaty mating surfaces.  Hard call to make, but if I had to put money on it I'd bet that it would work out just fine as is.  If I were doing it myself though... I don't know, it would be hard not to take it to a shop and have a couple thousandths of an inch taken off for as cheap as I can get that done around here.

In short, I think you should run it as is for science.

[70CB750]

I would skim it 0.010", but, I would skim it even if it hadn't been blasted 
Slight bump in compression won't hurt anything 

I think even less than that would smooth it out - the surface profile wouldn't be 0.2mm.

[trueblue]

The bead blasting won't hurt the sealing ability of your head gasket if you are using a standard composite gasket.  That merc head that was being "straightened" by machining is leaving the cams prone to failure.  When a head bows not only is the head surface warped so are the cam tunnels.  The correct procedure to straighten such a head is to first remove the cams and use the cam bearings as your reference point then with careful application of heat pull the head back into shape.  Once it is straight then run the head surfacer across it to ensure it is flat, you shouldn't have to take anymore than a couple of thou off to achieve this.  But back to the OP, your head will be fine, I would be more worried about the cam bearings having been hit with the bead blaster.  FWIW I have run heads that have had the gasket surface bead blasted on watercooled engines without an issue .

[754]

Keep in mind the other head may need as much or more work.

[Brady]

The bead blasting won't hurt the sealing ability of your head gasket if you are using a standard composite gasket.  That merc head that was being "straightened" by machining is leaving the cams prone to failure.  When a head bows not only is the head surface warped so are the cam tunnels.  The correct procedure to straighten such a head is to first remove the cams and use the cam bearings as your reference point then with careful application of heat pull the head back into shape.  Once it is straight then run the head surfacer across it to ensure it is flat, you shouldn't have to take anymore than a couple of thou off to achieve this.  But back to the OP, your head will be fine, I would be more worried about the cam bearings having been hit with the bead blaster.  FWIW I have run heads that have had the gasket surface bead blasted on watercooled engines without an issue .

Thanks for the note....no worries on the bearing surfaces as they only blasted the bottom side and ports... so topside is untouched.

[Duanob]

If you're really worried about the surface mating use some copper gasket spray. I use it anyway. haven't had a leak of any kind yet. Not even the oil passages that are prone to leaking.