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Here is what I don't get - the cylinder liners are proud of the block .That should set the block to head gap and provide good seal for the liners .As the head heats up it expands creating more clamping force on the liners .Assuming the head is reasonably flat why is there leakage ?

Have the hard copy? I can do a new drawing for you in OnShape.

I THINK the answer is that the head and block are flat on the bench but the studs apply a LOT of force and a piece of metal is just a big spring, it does deflect. For the middle cylinders the forces are pretty balanced...cylinder, bolt, cylinder, bolt, ect. At the ends there is no next cylinder, the stubs are acting on 1/2 the system and I'm guessing bowing the head....accent on guessing

Thanks, I'm working on exactly that now. I just wasn't positive there I made no other changes after I printed and market up the drawing before sending the file off. Normally when I have a copy with minor markups it means i saw no need to reprint and its right....normally

dumb idea but -if the head bolts are torqued middle out -wonder if retorqueing ends in would be flatter .

I have been wondering if I should torque the ends a bit less or maybe even reduce the neck OD on the studs to to give them a lower spring rate...don't know.

I went and took my coolant bath tonight to make tomorrow a little more pleasant. I see it flushed out more kseal so it will need to be filtered again before reuse but its out.

So by Ferrari's cockamamie cylinder numbering scheme, 6 & 7 are at the flywheel end and 1 & 12 are at the pulley end?

What does #1 look like? Is it the only end cylinder that you don't think is taking water?

Going to peek in with the bore scope again to verify water in the cylinder? Pressurized air into the cylinder to verify that it blows through into the cooling jacket?
Some amount of dorking around with it in the failed state *BEFORE* you disassemble it may help you understand what's happening.

Are you currently thinking that the cylinder head is potato chipping a little bit and letting coolant leak in at the top and bottom edges of the bore? Any way to tell where on the bore the coolant is leaking in?

No way this could be a tuning or ignition problem?

How proud are the liners from the deck? 0.002? Try a strip of 0.002 shim stock on the end of the deck to simulate the next liner?

I guess a Testarossa head gasket won't work.

Woah, a lot of questions

yes 6, 7 are flywheel, 1, 12 damper. ! looks ok but its all the best supported because of course #1 is further from the edge of the block than 12 (by 1 rod thickness, about .75" . 6, 7, 12 are all about the same, 1 is 3/4 more.

No plan to look in, I can I guess

there is no way tuning is letting coolant into the cylinders, I'm pretty sure of that. Timing is conservative, mixture very rich so little chance of doing damage...plus the leakers are 6, 7, 12...the ends meaning its not random.

cylinders are about 0.0015 proud. A 022 shime wouldn't do it I don't think.....the bore centers are 94mm so if the heads over hung the side3s by 47mm then the shim might do it, math wise anyway.

No on the TR gaskets because my bore is 86 vs 82? and I offset the head 1mm relative to the bore making 1 side even worse.

I'm pretty sure the failing an air leak test was telling me something important.........

the copper gasket are going to work a miracle though, no worries

I guess the ends are different in 1 more way, the block is supporting the liners on 3 sides instead of 2...that has to make then want to tilt a bit I'd think.

would the old gaskets fire rings provide any verification of " potato chipping " ?If the thickness varies around the circumferance could be a clue