4g64 head problem

[microgalant]

Well I've a 4g64 engine with a 4g63 head, running microtech stand alone.
The car is running on stock boost 10psi, last night I boost my car, once I push the brake in, I realize that the engine was idleing low, and bugging.
Went home, saw that smoke was comming out the breather nipple.(no smoke out the muffler)
Did a compression test, piston 1-75 psi,2-75 psi,3-165 psi,4-75 psi.
Went and took the head out, headgasket blew between piston 1 and 2.
Can some one explain to me why only one piston has a high compression.
And one question that I have is, do you guys think the rings and ringland is ok???

 

[microgalant]

Also, the headgasket blew from the part gasket to block...

 

[BogusSVO]

if a ringland came apart. you would most likely have scoring in the cylinder walls.

4 must have blown somewhere too, that is the only reason to be low on that one, 1 and 2 were swapping compression back and forth.

How was the head surfaced before? how much has been milled off it?

 

[microgalant]

if a ringland came apart. you would most likely have scoring in the cylinder walls.

4 must have blown somewhere too, that is the only reason to be low on that one, 1 and 2 were swapping compression back and forth.

How was the head surfaced before? how much has been milled off it?

yes the head was surfaced, but the one who did it for me told me that the head is not so good anymore,cause the engine had lean out one time, and it damage the head...
But if the ringland is gone, I should see some smoke out of the exhaust right?

 

[BogusSVO]

how did it damage the head?
I have fixed some messed up heads before, so what some shops call scrap weight, I call fixable.
can you post a few pics of the head?
you would see lots of smoke and scuffing in the cyl bore...

 

[microgalant]

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I've a 2g head here, wanted to pu that, but i don't know if the 1g intake will work on the 2g head, i know it bolt on though

 

[BogusSVO]

from what I can see in the pic, it dosent look all that bad.
Measure the head from the valve cover rail down to the head gasket surface.
New the head is 5.501 AERA says you can go to 5.185

looking at the pics again, I noticed the the head should be really thin.
still measure and find out and know.
I bet your compression is up a fair bit .

 

[microgalant]

I've a 2g head here, wanted to pu that, but i don't know if the 1g intake will work on the 2g head, i know it bolt on though

 

[spaugh]

The 1g intake has lager runners, but it will bolt up it will cause a lot of turbulence going into the head.

 

[microgalant]

The 1g intake has lager runners, but it will bolt up it will cause a lot of turbulence going into the head.

And what will that cause?

 

[BogusSVO]

the air flow from the intake into the head will "hit a wall" and bounce back into the intake due to the smaller intake ports in the head and the raised floor in the head.

also you will have to ream out the head bolt holes of the 2g head to get it to mount on the 6 bolt block.

personally, I would say sell/trade your 2g head and get a 1g


looking in the 2nd pic you have posted, I see the oil trough if alsmost gone, that should be about .080 deep. did you have lifter tic?

 

[microgalant]

Ok I went to a friend at the machine shop, he told me that the head is ok, and ask me how much I did torque the head (using arp 11mm studs), I told him 100lbs he than told me that, that is too much,so maybe that is causing that the head blew the gasket.
One more thing, if there is smoke comming out of the breathers on the head, does it mean that the rings are gone?

 

[BogusSVO]

Ok I went to a friend at the machine shop, he told me that the head is ok, and ask me how much I did torque the head (using arp 11mm studs), I told him 100lbs he than told me that, that is too much,so maybe that is causing that the head blew the gasket.
One more thing, if there is smoke comming out of the breathers on the head, does it mean that the rings are gone?

well are you running the factory headbolts? they are TTY bolts on the 11mm 2g, get a set of arp head studs.

and your head is way thin, get a thicker head gasket, or a head saver shim, did they measure the thickness of your head?

also just from what I see in pic #2 you should really do this mod...

http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html

how much smoke is comming out? the PVC just may be clogged or bad...

 

[microgalant]

I'm using 11mm arp head studs, and cometic 3 layer headgasket

 

[BogusSVO]

call arp and see what specs they tell you to use with that 11mm head stud.

you really need to step to a thicker HG, if your using a .040 thick gasket, you may want to get a .055 or even a thicker one.

 

[microgalant]

call arp and see what specs they tell you to use with that 11mm head stud.

you really need to step to a thicker HG, if your using a .040 thick gasket, you may want to get a .055 or even a thicker one.

But what will a thin headgasket do?pistons will hit the valves?
arp 11mm i checked it is 80 lbs with 30w oil and 65 with chromoly lube

 

[BogusSVO]

But what will a thin headgasket do?pistons will hit the valves?
arp 11mm i checked it is 80 lbs with 30w oil and 65 with chromoly lube

its a matter of compression.... for .008 milled off the head you close the combustion chamber up by 1cc

from pic #2 i see the casting injection spot has been milled, so I would have to say your head has been milled ALOT.. somewhere around .040 or more. that is a guess since I do not have a measurement spec to work with.
also make sure you port the oil trough so you do not starve the head for oil...
http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html

Using a THICKER HG will help restore you closer to a stock compression ratio, and get your belt timing back closer to stock setting

when you mill an OHC head, you get a natural retarding of one cam and an advace of the other.

due to the change in the center line of the cam to crank.

 

[microgalant]

Ok, I've put a new cometic headg on my car, it was knocking like crazy, my tuner had to put the timming to 0 so it stops doing that.
I've put new arp head studs and cometic 3 layer headg 0.51 mills.
After dyno it my car was fine, till 2 weeks ago, it begin to overheat again.
Water goes into the water overflow tank.
What i've checked: put new radiator cap, fans are working ok.
What do you guys think will be the problem? bad radiator?
I'm using a second hard radiator, from a 8g galant, on the radiator it has a water cap, and one more cap on the water neck.