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Discussion Starter #1
4G63 Head Build – Modified



I am going to skip the tear down and tech, and start, a basic clean casting.

The guides are good, and I am going to use the customer-supplied parts.

>Manley single springs, Spec sheet 66 lbs @ 1.580
>EPN-Engnbldr Std size Stainless Steel valves


This head was also Belt surfaced, So I have to do a corrective mill to square the head.


I set it up on the grinding bench


I know this head will see turbo use.
I inked parts around the combustion chamber and etched with a head gasket.


Did oil port Mod 1



The sharp edge of the combustion chamber was beveled down


A slight champher was done around the rest of the combustion chamber


The runners had some cast flashing removed




Now was time for the valve job, start with a basic 3 angle valve job



Checking seat placement on the valve.


Now I will do a throat cut.


Notice the difference this makes, See the lip under the seat insert with the rough casting, (left bowl)

The bowl on the right had the throat cut.


This leaves a lip also, this is a STD size valve. With a +1mm os valve there is more of a lip


Now the lip needs remove and blended in.


The valves are ground.


Then lapped in and back cut


The head is CBN milled


First cut .003


Another .004



I milled another .002 to finish square the head.

Had a bad exhaust stud hole, so a heli-coil fixed that.



Valve tip height is checked,
The springs are checked
Spring installed height is measured.
Springs will be installed at 1.530 @ 80lbs

Shims are placed on the head.


Then the stock spring pad and Vition blue stem seals.


Springs are then buckled up .


The head is now ready for HLAs, followers, and cams and cam caps.

I have posted the head as it was shipped to me.
http://www.dsmtalk.com/forums/showthread.php?t=242634
 

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nice job friend...
Why since the head was out,didn't you grind out all the castings left overs from the upper side of the head near the spings?
I trimmed them out in mine because i saw little pieces of cast scatterd all over the head when i washed it right before i installed it.
The same goes for the oil return holes in the center of the heat where you can clearly see the joining of the casting....
 

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Discussion Starter #6
Nice work.
Thanks!!

Is this Scotts head that was for his Galant vr4 last year?
IIRC Yes it is.

nice job friend...
Why since the head was out,didn't you grind out all the castings left overs from the upper side of the head near the spings?
I trimmed them out in mine because i saw little pieces of cast scatterd all over the head when i washed it right before i installed it.
The same goes for the oil return holes in the center of the heat where you can clearly see the joining of the casting....
Yes there is a ton of cast flashing in the top of the head, and some to get the grinding done on them , but not all.

But all do get the flashing removed from the oil returns.
 

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So thats's what Allen ended up sending Scott. I was talking to Scott the night he was trying to start the galant before he found he had no compression. He never did say what was wrong, but he did mention he'll never go to SIM for engine work again.
 

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Discussion Starter #8
If you check out the link at the bottom of post #1, you will see how I received the head from Lofty
 
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