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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
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
