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the "head lift" fix

126K views 421 replies 107 participants last post by  permanent grin 
#1 ·
ive been holding out on eveyone for a long time hear reading about what everyone is calling head lift...watching it go from gaskets to studs to it can only be detonation etc etc. i wanted to keep quiet untill all my testing and research was finished.

like ive said in the past, its not the head lifting rather the deck of the head is not strong enough to handle X cylinder pressure. that number gets lower the more the heads are milled.

there are 2 areas where the deck is not strong enough to keep it from bending. that is the deck surface near the center of the intake valves AT the gasket ring and the same on the exhuast side. if you look in the coolant pasages under the deck of the head you will see that this area is hollow and relies on just the thickness of the deck for strength. the rest of the sealing ring area is solid aluminum and has no flex.

if the studs were not strong enough and the heads were "lifting" there would be also leakage in other areas of the ring area ie. between cylinders and other areas where the head is also solid. the deck itself is not strong enough to stop from flexing in these 2 hollow areas.

my fix... machining out those hollow areas and installing aluminum stantions in those areas just benieth the head gasket ring and welding the areas back up. this leaves no more hollow area under the gasket fire ring that will flex out of the way and still has room for coolant in the area.

ive done alot of testing here, before and after using presses and measuring flex in these marked areas where i always see them leak.

studs, O ringing are not the answer.

if anyone wants this done, i will be performing this service start to finish including a finish mill for approx $550 per set of heads.

sorry for taking so long to post this but i never post guess work.

Ray
 
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#5 ·
Coal said:
I've been waiting and waiting, thank you for the update Ray! :D

Studs and o-ringing couldn't/wouldn't hurt as overkill would they? I have ARP studs, and stage 3 heads sitting that I haven't installed yet, and I love overkill.
studs are fine.. O ringing may not last long if there is any gasket movement going on. O ringing without supporting the weakness in the head will not work much better than having no O ring at all.
 
#6 ·
This totally makes sense Ray is the man!!!, I actually thought about that area in the center coolant passages and wanted to install smaller studs offset, eliminating one out of the two collant passages in block and head, but after looking at the head it was clear that we would run into the oil tunneling issues. This would be a pain in the ass..Unlike Ray, i had no r&d, just going by what i saw and didn't know for sure if this would help.

Awsome work Ray, and it is pretty affordable..
italo
 
#9 ·
Ray you should change your forum name to "THE MAN" .

Keep up the good work.
 
#10 ·
I dont want to steal any work from you, but do you have pictures of the affected area your talking about the a finished pick of your solution? I may just be sending you my heads too...
 
#15 ·
not really Mark. if you weld them solid there wont be enough coolant near the chamber/valve area. the engine will run cool but cylinder temps would be extreme and it would have shitloads of knock. if you just close the holes and get water to the heads external you will still have deck flex unless you build stantions under it.
 
#16 ·
Ray,

Been watching your quality work for some time; thanks for all the advances to this
platform.

With your new forged cranks + head work solutions, how much boost do you
think a built motor made by you can safely run on race gas before running into issues? (Forged crank to fix spun bearings + head work to now correct sealing)

Thx,
Nobs
 
#18 ·
nobs said:
Ray,

Been watching your quality work for some time; thanks for all the advances to this
platform.

With your new forged cranks + head work solutions, how much boost do you
think a built motor made by you can safely run on race gas before running into issues? (Forged crank to fix spun bearings + head work to now correct sealing)

Thx,
Nobs

thank you.

its going to depend on cylinder pressure..or how the boost is used. cylinder pressure is where the power is. looking at it that way, you should be able to get pretty far in boost.


my engine was on the edge of pushing coolant and mainbearing problems at just under 900AWHP. that was 30-32 psi. i left it there and all was fine. if i ran more boost i would run into the bearing issue and or coolant with the shightest of knock..maybe no knock at all. i know this will be able to go waaay more now.
 
#19 ·
it is ALWAYS combustion chamber to top/bottom coolant passage blow by and never chamber to chamber.
Totally makes sense.
hats off to you ray
Hope this is truly "it"
Sounds plausable, makes good sense, and you have tested the hell out of it.

GOOD SHIT!
 
#21 ·
ray pampena said:
coolant and mainbearing problems at just under 900AWHP. that was 30-32 psi. i left it there and all was fine. if i ran more boost i would run into the bearing issue and or coolant with the shightest of knock..maybe no knock at all. i know this will be able to go waaay more now.
Ray - But aren't we still plateau'ed at the ~875awhp level with a built 6G72 due to crank flex/bearing failures?
 
#24 ·
GTO NEMESIS said:
Ah yes forgot that my drag chap runs Top Fuels :(

Would your method strenghten the area melted on this pic?




Thanks
Mark

We did that EXACT thing to a head, blowby combustion gasses melted the head EXACTLY like that. Good to know we aren't the only ones.
 
#25 ·
pyun said:
Ray - But aren't we still plateau'ed at the ~875awhp level with a built 6G72 due to crank flex/bearing failures?
thats a tough question to answer while typing but ill try...

with MY turbos? yes. because it took X cylinder pressure with X back pressure to make X power. if i ran anymore boost the cylinder pressre would be at the crank bending point if i pick up the slightest knock. if it was able to make the sensor read it was enough to smash the mains. 875 was a happy spot.

now run larger turbos. you can get MORE hp with the SAME cylinder pressure due to less back pressure to operate above turbos. the problem with that comes alot more lag.
 
#26 ·
ray pampena said:
thats a tough question to answer while typing but ill try...

with MY turbos? yes. because it took X cylinder pressure with X back pressure to make X power. if i ran anymore boost the cylinder pressre would be at the crank bending point if i pick up the slightest knock. if it was able to make the sensor read it was enough to smash the mains. 875 was a happy spot.

now run larger turbos. you can get MORE hp with the SAME cylinder pressure due to less back pressure to operate above turbos. the problem with that comes alot more lag.
that's what the bottle is for...just up those jets man ;)
 
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