The extension is the straight edge... read it a couple of times. google it, read it again.

well now that I know the extension is the straight edge googling might turn up something. Should I start with hilbilly perf4mans tekneeks?

So many lolz in this thread. Here, let me help you: https://www.miataturbo.net/engine-pe...ht-edge-70246/

So I just assume the glass is flat? and the extension only has one arc? why not just use a ruler or square?

I measure .006 warpage right at the cats torso between the cylinders. Of course this is with my jank arse square. It will hopefully be going to the machine shop tomorrow and hopefully within the week be complaining about how much it costs to check and to shave off a few thou.

Working on cars when it's cold sucks.

costs usually between 40-60

make sure they use an actual mill, and not a belt sander

belt sander = run away from that shop and never look back

The dremel belt-sander attachment works pretty good though :party:

actually I was jus gonna glue some sand paper to the sidewalk and rub the head around on it and finish it up with my harbor freight belt sander.

40-60 is really reasonable I am down with that!

The shop I use has all the proper equipment. I would never use a shop that uses a belt sander to surface a head!

They even got this dope crank balancing setup.

You are missing an intake nut btw.

Yeah some wank must have left it off when it was rebuilt maybe the same wank who left the exhaust manifold bolts loose.

I will be rectifying this situation shortly.

Well I doubt these updates are very interesting but hopefully posterity will find them useful.

The machine shop says a .008 straight razor shave will fill the bill. They were also concerned with the indentions around the chambers. I noticed this as well. There were lines around the chambers I guess from sealing ring of the gasket that got pressed into the head. They were smooth but could be felt with the finger nail. It wasn't all around the chambers just in spots.

I would take a photo but I doubt it would be visible. The moral of this fairy tale is if your head isn't smooth and flat for whatever reason you are gonna have a bad time.

The motivational speech at the end is boss.

So let's see, a couple of hours for the sanding, probably at least $100 worth of sand paper and glass and so on to avoid a $45 machine work?? At least good for lolz.

Yeah seriously! My machine shop quoted me $60 for a head resurface.

Sure the guy might sand away the marks and stains from the gasket but how does he know its square to the rest of the head? Also just because he uses a ruler doesn't mean his ruler has any kind of accuracy he might be close but from what I understand a MLS sealing surface needs to be within .002"

I do give him credit he thought things through at least by mounting the sand paper on a board he checked with is ruler and knows how to check a head for flatness but its his ruler thats his problem and his false economy of doing it himself rather than paying a machine shop to do it.

LOL I didn't even last long enough for the speech. I figured it was some kind of lameness that would make me cringe. I dont have a high tolerance for the cringe. Did you read the comments? Dude is defensive and defending himself to everyone its hard to read. He doesn't really deserve the crap he got. Sure he should just take it to a machine shop but it's obvious he did his research and at least put some thought it this process. But my opinion is I would rather it be done right the first time rather than risk messing up a head or having to do it again cuz my ruler is off by .003"

machinist much success super good! $62 including cleaning.

I heard by my tailor that the round cast areas highlighted in green are the limit a head can be machined is he correct or can it be blamed on poor breeding that he would feel to tell me such lies?

Hmmm interesting.