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The dark shall be with us
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Discussion Starter #1 (Edited)
So I know the pyramid ring head gasket has been pretty successful so far but it still require block machining and expensive Head gasket (which is a one time buy but still). Before Andre offers pyramid gasket, I bought a beat up cylinder head and started cutting around the head gasket fire ring to see why the deck flexes so much. It turned out the area under the fire ring is empty on both the exhaust and intake ports. It is worse under exhaust port. I was going to do this if the heads were not sealing with the pyramid rings but I think this will hold just fine with an o-ring block and factory head gasket too.
All you have to do is machine the area under the fire ring on each end and weld the area all the way to the top making it solid under the fire ring. If you look at the 2jz heads, the area under the fire ring is solid and not hollow under the fire rings like ours. I think anyone who does aluminum welding or even cylinder head repair that are damaged by a valve drop can do this work.
I marked the area that needs to be cut and rewelded with red marker, that way you don't have to weld the entire heads and prevent coolant flow.

I don't know if you can tell by the photos since it's hard to get the picture without actually looking at the head in person but if you pay attention, I cut the head three different way one was to drill right at the fire ring area and you'll see how thin the metal is there in two of the photos. in the middle I cut it a lot to see how far back the hollowness goes and on the right I cut the head just up to where the fire ring is to show the thickness of the area where the fire ring seats.
I left one 2jz cylinder head photo to show exactly what I mean when I said fire rings under 2jz head gasket are solid but empty under our heads. If we weld them all the way down, this will prevent flex.
I also left a Honda cylinder head photo to show how it'll look when they are welded.
I sometimes thought about not welding the area but to use a epoxy glue that are metal based (like the ones Honda people use to make the cylinder walls stronger) and just shove them underneath the area where fire ring sit and support the head from flexing. I know that won't be as effective but might actually do more than enough for most people.
Ohh and that rod you see sticking out of the head is actually a drill bit that broke and I can't get it out. Lol those areas between the heads are pretty thick. The hollowness only is around the holes that water flows between the block and the heads. If Mitsubishi cast them in those areas maybe 2 to 5mm more, we wouldn't have such big problem.


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You do realize that all you're doing here is "re-inventing" the current headlift fix, right?

Ray identified the exact weakness you're describing about a decade ago, but instead of welding it all up as you're doing he drills a hole on the fire-ring, installs a pin that supports the deck, and then welds the pin into the deck finishing it up by (i think) planing the head.

The exact same issue, and exact same fix, exists on some older v8 heads. My local machine shop knew exactly what I was talking about and exactly what the fix was when I pointed out the weak spot in the heads and described ray's headlift fix. They were very familiar with the process and according to the old guy there they'd done it on "hundreds of heads over the years" for local dirt track racers. The only difference they described to me was that they drilled a much larger hole than I was describing and used a larger diameter pin with a threaded end and they tapped the hole. This let them pre-tension the pin before welding it.
 

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I'm not trying to steal your thunder... or discredit your effort in trying to understand where the shortcomings in our engine are... just that I think you're lacking a bit in the up-front research about what we know and think we know, and the result is you spent a lot of time and presumably money figuring out something that was already known and published.

From 2007....

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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The dark shall be with us
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Discussion Starter #4
The pin didnt work as good as we hoped. People still lifted heads around 1000 whp if you were more agressive on boost or timing. I don't think he welded the pins. It's a threaded rods and was screwed into the head and then cut short.

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I think once you get up that high, then yes you're lifting the head. Which means we're really talking about 2 distinct problems, with similar end results.

Problem 1: this one isn't head lift, it's deck flex. This is what both your fix and rays fix solves. It takes the weak spot in the deck that gives under high cylinder pressures and reinforces it. This failure is characterized by the failure always occuring at this weak spot.

Problem 2: this problem is true head lift. This problem the failure can happen anywhere around the ring though as with any gasket there are some spots more prone than others. This problem is solved with the heavier duty head bolts and the pyramid ringing or o-ringing.

Some of the really big builds like Italo's and/or Leonels if I remember correctly used both rays fix and one of the others.
 

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The dark shall be with us
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Discussion Starter #6 (Edited)
Problem 2 is not a true head lift. No way you are lifting the head with only 170 hp per cylinder or 500 hp per head. Not to mention people already have studs installed and our studs are almost same size as 1/2 ones that other people upgrade to. People make 3000 hp out of stock 6 cylinder heads without pyramid rings. I got the Ray head lift fix. He doesn't put the rods under the fire rings (there is no way you can since there is no room and the support is not holding the whole area. It's not just one spot that is thin. It's the whole area so if you support one spot, another spot flexes. Ray put the pins where previously other people burned through the head. He put pins way after the cylinder head fire ring so the deck is still flexing under the fire ring since the thickness is still very thin. He did say something about cutting and rewelding the deck later since people still pushed coolant with his head lift fix. Maybe he wanted to do the same thing as I do.

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devilmightcry, Erron S. did the same thing your wanting to do. His head lift rods didn't seal and he proceeded to weld those coolant passage areas after he reviewed cut up heads. So far its been working for him and his crazy 12:1 setup at the tracks and long endurance laps
 

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Weld the head solid, fill the block, o-ring/receiver groove with copper gasket, and run methanol, problem solved. But we’re afraid to specialize around here....
 

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1G Foglights b!tches
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DMC, dude, really? Everyone now knows about this. and welding heads is nothing new.
 

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Discussion Starter #11
devilmightcry, Erron S. did the same thing your wanting to do. His head lift rods didn't seal and he proceeded to weld those coolant passage areas after he reviewed cut up heads. So far its been working for him and his crazy 12:1 setup at the tracks and long endurance laps
Glad to see someone has tried it already.

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Discussion Starter #12
DMC, dude, really? Everyone now knows about this. and welding heads is nothing new.
Then Why on Earth people didn't do this and kept pushing coolant for years ? I have seen someone welded the whole deck so I thought people didn't know about this. I don't think this is going to be expensive to do. I thought people did something like this which would only make it good for drag racing and that's why they didn't want to try do it.


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Then Why on Earth people didn't do this and kept pushing coolant for years ? I have seen someone welded the whole deck so I thought people didn't know about this. I don't think this is going to be expensive to do. I thought people did something like this which would only make it good for drag racing and that's why they didn't want to try do it.


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Because matt ran 8’s with a piggyback.

For decades this community was shit. Shop cars went fast, broke every other run, and pretended they didn’t.

Meanwhile dsm’s Went fast, broke, info on failure was shared, and the community moved on to the next failure point.
 

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Because matt ran 8’s with a piggyback.

For decades this community was shit. Shop cars went fast, broke every other run, and pretended they didn’t.

Meanwhile dsm’s Went fast, broke, info on failure was shared, and the community moved on to the next failure point.
Yeah, pretty much.
 

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Discussion Starter #16 (Edited)
Because matt ran 8’s with a piggyback.

For decades this community was shit. Shop cars went fast, broke every other run, and pretended they didn’t.

Meanwhile dsm’s Went fast, broke, info on failure was shared, and the community moved on to the next failure point.
Yeah I can't figure out why after many years people didn't solve the obvious problems instead what they did was moving on to other platforms that people already solved the issues for them already. I would do this instead of port and polish heads if you are on the budget and want big power. But I'm not a shop so this would not net me any profit. Just something to proof.
I had an itch to try this with aluminum rods on a 3L with my bearings stock heads with cams to see if the engine can make 1000-1200whp without breaking to see if people can use these engine and not spending too much money for big power.
Seems like Erron is the only one who did this and he's having no problem doing 800whp pulls at the track back to back.
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1G Foglights b!tches
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My point is that you are making it seem like some huge discovery that there is a cavity. Hell, there have been full cutaway’s of 6g heads posted already. And the heads are very similar to a DSM. Cutaways of those exist as well.

Ray feels like his approach, is the solution which is a threaded insert that also puts tension on the deck. If he thought welding was better, I bet he would have them welded. It’s not like literally thousands of shops across the country aren’t welding aluminum heads already.

Also, if a head gasket blows, they are changeable. You don’t have to part the car. Not sure if you knew that.

The dual oring and composite worked great for me with 4g. Clamps down from both sides and pretensions the head deck also. I like having the gasket as weakest link. That way if something goes really wrong, it blows like a fuse first instead of holding it all in and shoot a rod out the block. You just need it to hold enough normal cylinder pressure. Then when it’s abnormal, it blows.

And speaking of cylinder pressure. Read and Reread. This community needs to stop chasing timing. Put a turbo on that isn’t choking up the whole system and turn up the boost.

 

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Yah, above suggestions are good, but what about people that want street strip cars? Welding the whole area is impracticable, and running methanol. For a drag only car this is great but not a street. Ray only adds one threaded rod, i wonder if someone were to add more to support the whole area would be better?
 

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Apparently brian is running unfilled heads with no head lift fix ive been told i wonder what hes doing to stop his heads from pushing???? Maybe hes being secretive like every other 3ser in this platform, another contributing factor why we cant get ahead. Oh, and nelson as well. I dunno what the big secret is though.....
 
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