Measuring how much a head was shaved?

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Krooser

Krooser

Building Chinese Free Engines since 1959...
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Ok....so I'm home recovering from surgery and I am finally able to limp out to the shop this morning.

So I'm cleaning and organizing my engine assembly/parts area and I keep staring at my shiny redone W-2's and I wonder "how much have these heads been milled"?

They were new in '94...ran 18 nights...sat under the bench until 2007 then it was loaned out by the PO and the motor blew.

I bought it broken three years ago.

So my shop redid the heads, new valves, etc and took a skim cut. The oring grooves are still visible from the original build.

Where do I measure?
 
Krooser said:
Ok....so I'm home recovering from surgery and I am finally able to limp out to the shop this morning.

So I'm cleaning and organizing my engine assembly/parts area and I keep staring at my shiny redone W-2's and I wonder "how much have these heads been milled"?

They were new in '94...ran 18 nights...sat under the bench until 2007 then it was loaned out by the PO and the motor blew.

I bought it broken three years ago.

So my shop redid the heads, new valves, etc and took a skim cut. The oring grooves are still visible from the original build.

Where do I measure?
Click to expand...
This will be an interesting thread. The machine starts with the original deck and removes .*** amount. I'm not sure you can somehow reverse that and measure to find out how much. Anybody have factory machining dimensions?
 
One if the shops I deal with will roll those Chevy heads and angle mill them but not so much as to make it visible to the track inspectors.

They did my sons modified motor and I told em to shave 'em all he could. When we put the engine in one of the guys helping us asked if we had a 12-1 motor...rule sez 9-1.

Ran like 14-1.
 
Krooser said:
Ok....so I'm home recovering from surgery and I am finally able to limp out to the shop this morning.

So I'm cleaning and organizing my engine assembly/parts area and I keep staring at my shiny redone W-2's and I wonder "how much have these heads been milled"?

They were new in '94...ran 18 nights...sat under the bench until 2007 then it was loaned out by the PO and the motor blew.

I bought it broken three years ago.

So my shop redid the heads, new valves, etc and took a skim cut. The oring grooves are still visible from the original build.

Where do I measure?
Click to expand...


If they are open chamber you can measure the quench pad. IIRC it should be .090-.100 deep. Or you can measure the chamber volume, which is what you have to do if they are closed chamber heads.
 
I got messy cc'ing the heads a couple months ago. Going to do it again when I get enough strength back... Open chamber btw.
 
Maybe cc the heads and compare to what the heads were originally advertised at, or measure against and uncut set.

I bought two sets of J heads off a friend of mine, one set was un-cut, the other pair had .125", no typo 1/8" milled off them.
The pair that was milled the fly-cutter actually started to cut the top off of the casting numbers.

iLx7RH.jpg
 
sireland67 said:
Maybe cc the heads and compare to what the heads were originally advertised at, or measure against and uncut set.

I bought two sets of J heads off a friend of mine, one set was un-cut, the other pair had .125", no typo 1/8" milled off them.
The pair that was milled the fly-cutter actually started to cut the top off of the casting numbers.

View attachment 1715640968
Click to expand...
Yep, turned them into a closed chamber. Makes your header tubes drag the ground. :poke::rofl:
 
I had that same shop do a set of J heads for me. He angled milled them and we found an inclusion in the casting in the combustion chamber.

I wound up selling them but I took a loss because of that stoopid little chunk out of the casting.
 
Pondered this, and maybe I'm full of hooey- to my way of thinking you'd have to reference the cut against another machined surface, and the only semi-reliable one would be the rocker shaft saddles, which should be cut to a fairly standard dimension from the deck surface... So (if they're econo W2s with cast-in pedestals) would you be able to use the distance from the newly cut surface to the botton of the saddles of the shaft pedestals, compare to a set of uncut heads and come up with a close number? Of course this goes out the window if the W2s have separate rocker stands.
Crazy?
 
I'd think without knowing the depth of the original o-ring cuts, you're not going to know unless they kept a record. You could estimate a skim cut, that didn't obliterate the oring grooves, maybe a sheet or two of paper? 3 to 6 thou?
 
Don't know if this will help, I think(?) it's from one of my old DC books. Now it's just another picture on my computer...

FABO001_zpsc596184d.jpg
 
I wonder? If the tops of the head bolt bosses are a "standard" height?
 
Just spoke with the shop foreman... He said they just did a skim cut to be sure the surface was flat.

He also said they are dealing with parts shortages...cant get juice lifters from Hylift Johnson or Melling.
 
no markings on the heads from the machine shop, as to how much they milled em?

that'd be too easy, right?
 
diymirage said:
no markings on the heads from the machine shop, as to how much they milled em?


that'd be too easy, right?
Click to expand...
I was told maybe .003-.004. Just wanted to be sure they were flat. These were low lap heads...maybe 20 nights since new.
 
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