Anyone drill a hole in the head above cylin #6?

[kylefoto]

Okay.
So I've got my head off right now fixing the BHG, and I was talking to whenmunkysfly tonight.
He had noticed that above cylinder number 6, there is a hole in the block and gasket, but not one in the head. Check attachment with circled hole at the top of the picture for reference.
Has anyone drilled that hole in the head and had any problems? You would think it would help cool that cylinder better, especially seeing as most BHG's are in #6...

 

[Jaguar_5]

Wtf... that can't be good!
Get a close up! Start taking that gasket off, don't sleep!!!!!

 

[kylefoto]

Wtf... that can't be good!
Get a close up! Start taking that gasket off, don't sleep!!!!!

what?
drilling into it?
I'll get a close up tomorrow.
my back is killing me.
go check my build thread, gasket is off.

 

[Jaguar_5]

Yeah, If you want to get heat away from the combustion chambers, iron conducts heat better than air, so i don't know why the hell someone would drill into the deck!!!!

 

[kylefoto]

Yeah, If you want to get heat away from the combustion chambers, iron conducts heat better than air, so i don't know why the hell someone would drill into the deck!!!!

Yarden,
you forget that I don't know much about engines.
Explanation in dumbed down terms?

 

[ViR2]

dont do it <-- In simple terms

 

[CBLEGUY]

My 90 has the same thing but reversed. the head has a port in the back next to #6, but the block does not. The gasket also has this port. I think it was an afterthought or something.

 

[lintlars]

theres another thread about this I cant remember if it was here or SF someone has done this Ill see if I can find it.

 

[MKIIINA]

the "hidden" passage is normal. You can drill it out and coolant will flow to the back of the motor. There was a thread over on SF about this as a "How-To" and we did it on my brothers car when the hg went w/o any ill effects.

heres the thread:
http://supraforums.com/forum/showthread.php?t=318284&highlight=hidden+drill

 

[Jaguar_5]

Woah... so this opens up a coolant passage!
Kyle, does the hole go all the way through into the coolant passages? In the picture i thought it looked like the bottom was metal, not open. Is there a matching hole in the head?

I might have to do this one...

 

[kylefoto]

Woah... so this opens up a coolant passage!
Kyle, does the hole go all the way through into the coolant passages? In the picture i thought it looked like the bottom was metal, not open. Is there a matching hole in the head?

I might have to do this one...

I think that there is a hole in the block, I need to double check, it was late last night, but there is a matching one in the head.
MKIIINA, how long has your brother been running it like that and what kind of HG did he use ect ect?

 

[whenmunkysfly]

I think that there is a hole in the block, I need to double check, it was late last night, but there is a matching one in the head.
MKIIINA, how long has your brother been running it like that and what kind of HG did he use ect ect?

ok guys i read up on it alot a long time ago and from what i read(and by drilling out my own head) there is a passage about 10mm down into that head by drilling down to this you get more water flow to the back of the head where most of your BHG's come from there are more holes the you can drill out as well on the intake side of the head but i desided not to do them because i thought it would affect the flow on the exaust side too much.

 

[NashMan]

hummmmmmm i found out some thing intresting about this hole drill hole thing

it's there to incresh heat in the egr to be more clean burning?

the ture case to this is does jdm head have the hole

cause toyota made 3 diffent casting's of the head

this may just be it or not i herd they made 2 diffent jdm casting's but i have no pruff of this being ture cetp here say from some peoepl off sea's

 

[MKIIINA]

he has been running it for over a year now with no ill effects. 1.2MM HKS MHG/ ARPs @ 90ft/lbs. Hes running about 10 psi of boost through a hybrid turbo at around 315-320rwhp.

 

[NashMan]

has any one looked at jdm head closely or know if there was any changes though out it's life

 

[kylefoto]

Sorry nash, I forgot to reply to that post of yours.
I have a JDM engine, and no hole in the head...

 

[NashMan]

did japan care any thign for emisson's at all just woundering cause this si the onlt thgin i cna think of whay they whould do this in less drilling that spot whould lower the persures in other ares in the head/block and kidna bye pass the others

i think it has to do some thgin wiht eh egr heatign up the cyc to burn exases gases but hummmmm

 

[Boostedstr8six]

First time I've heard of this...

Anyone have any pics of a drilled out head?

Remember, the thing bolted to the back of the USDM head is called an EGR cooler.

 

[whenmunkysfly]

First time I've heard of this...

Anyone have any pics of a drilled out head?

Remember, the thing bolted to the back of the USDM head is called an EGR cooler.

i would have taken a pic but my head is bolted back up now.

 

[Doward]

did japan care any thign for emisson's at all just woundering cause this si the onlt thgin i cna think of whay they whould do this in less drilling that spot whould lower the persures in other ares in the head/block and kidna bye pass the others

i think it has to do some thgin wiht eh egr heatign up the cyc to burn exases gases but hummmmm

I'm sure it has something to do with the EGR cooler on the back, yeah... maybe a little extra heat, to ensure it doesn't cool too much, would be my guess. Keep the carbon from forming in it and blocking it up!