Hey guys, have a look at the cylinder head off my 91 VR-4, 160,000 miles, i bought it from the original owner and he said it had never had internal engine work. He gave me every receipt he had for the car, always serviced by the dealer and had 3g lifters installed when the old ones ticked. he was religious about oil changes and gave me a stack of receipts proving it. inside the head was a light amber coloring to the aluminum but otherwise it was extremely clean, the outside of the head was filthy from years of driving it 100% stock and just maintaining it.

Surface appears to have a ton of resurface meat left,

how it came off the car;


after a quick tear down and cleaning;



Isn't the rectangle shaped flat spot over the #1 runner where machinists' mark each time they machine the head?


The meat;

Wear pads don't look like they've been touched so I'd say it's a virgin head.

It looks pretty original to me. I'd say the biggest giveaway is the chamfer that's still largely present on the head bolt holes. On a machined head, that begins to disappear.

The head that's currently on my car was machined down pretty good. There's a substantial difference between mine and the pics you posted. If your head was machined, it wasn't cut much.

Here's a few shots of my head:

BogusSVO did some really nice write-ups that might give some insight into the situation with remaining meat, as compared to a stock depth of the entire head.

Also check the depth of the oil feed hole.

Jafro does some awesome videos on the cylinder heads and you are likly to find the information concerning how much meat should be there too.

It looks pretty virgin. Especially if there is material well above the valves at the circumference of the combustion chamber.

You'll be porting the oil feed hole as a precaution anyways, but record that number if you can, before and after.

Has the head been checked for flatness by a shop?

Or just look at the wear pads that Mitsubishi cast into the head to know when it's past it's limit.....

hey Jim, would be kind enough to clarify these wear pads?

i did not get that...

If you get the head resurfaced and it machines the plug in the center the head is considered below the limit. It's also a good indication if your machinist took material off level and didn't throw the thing on a belt sander and make it not parallel anymore.

I'm not sure what the factory new spec is but measuring from the center plug to the surface right next to it will tell you how much you have left to take off.

I found these numbers on the net when checking my head 5.193" - 5.201" factory spec. There are tabs cast into each end to measure the thickness from the deck to the valve cover gasket surface

thanks Jim and BEN!

is this on the tech manual, by the way?

I haven't actually read the manual to check for that spec but I assume that yes it would be in the factory service manual.