Cylinder head lift during duno

During duno the engine started to doping coolant. This just happend during boost(1064hp). For each pull it pushed out 2liters of coolant at 3 bars of pressure.

I am running titans head studs.

From my point this happens due to head lift. Proberly need to re-torque the head studs or that the head was not machined properly. What do you guys think?

Sounds and looks expensive either way

Sounds and looks expensive either way

No worries mate. That also the oem diff was failing will cost me more....

Could be head lift. Might be worth getting the head pressure tested too. Is there evidence of coolant around the bottom of the cylinder head after it has done this? Seems a bit weird if it would just pressurise internally only to that amount

Could be head lift. Might be worth getting the head pressure tested too. Is there evidence of coolant around the bottom of the cylinder head after it has done this? Seems a bit weird if it would just pressurise internally only to that amount

You mean that it could be a crack in the head?

No evidence that thete is coolant around the cylinder

I am thinking of remove the head and measure it to se if it badly machined and crack testet it. I havent hear that a block would crack?

Yes, blocks do crack. Check for cracks around water holes in the block once head removed.

There is always something to learn I have never before hard that a 2jz block has cracked. I will remove the head then and inspect that is going on there.

If there where a crack in the block it will be shit! Too much money in that block and I suppose repair is not possible?

Thanks V8kilr!

Yes, blocks do crack. Check for cracks around water holes in the block once head removed.

The reason I know they do crack is that mine did so between the front head bolt hole and the closest water jacket hole. I swapped to another block, but the block was welded up and used in a lower power setup with no issues. Might have been okay for me, but I didn't want to take the chance. Yours may just be lifting the head, so it may be time for bigger and/or stronger head studs, unless Titan studs are already the best you can get?

Ouch, glad to see you're taking it well, I'd have let out a few tears if I saw that!

Could a oem thermostat be able to create this pressurise? Due to higher rev for example

Could a oem thermostat be able to create this pressurise? Due to higher rev for example

No.

So I have removed the head but can't find any cracks either in the head nor the block. But it seems like the combustion has moved outside the expected area. See picture.

I thinking about to machine the head again and go with the HKS head gasket instead of the multi layer ones.

I would just accept that you are going way beyond the design limitations of the head and block and turn the boost down.... But if you are determined to see how much abuse you can give these things and aren't afraid of spending money then Wills rings and a custom fibre gasket to seal the oil and water ways might be worth investigating.

1000hp aren't so much these days and there are plenty of 1000hp supras in small sweden so it should definitely be able to handle the power somehow.

I would just accept that you are going way beyond the design limitations of the head and block and turn the boost down.... But if you are determined to see how much abuse you can give these things and aren't afraid of spending money then Wills rings and a custom fibre gasket to seal the oil and water ways might be worth investigating.

How does your compression & boost compare with other 1k Supra's?

If you won't drop the boost, you may need to drop the compression?

Before the head is machined make sure its flat by running a verdict clock along its width and length

Can you not get the head pressure or flow tested by a machine shop to tell if it's cracked?

How does your compression & boost compare with other 1k Supra's?

 

If you won't drop the boost, you may need to drop the compression?

Yes, Maybe I should use a 2,0mm head gasket instead.

Compered to other 1k 2jz engines I don't see any difference in the spec's.

Can you not get the head pressure or flow tested by a machine shop to tell if it's cracked?

Is it possible but due to the overpressure in the system was only shown during high boost is it not so likely that you could get at minimum 100bars pressure. (that is what at least have in the cylinders.) I am thinking of a Dye penetrant test otherwise.

Before the head is machined make sure its flat by running a verdict clock along its width and length

Yes thanks! I think the machine shop that did the machining last time used to high speed so the surface was not perfect smooth so they some manual hand polishing....

Yes thanks! I think the machine shop that did the machining last time used to high speed so the surface was not perfect smooth so they some manual hand polishing....

Never heard of manually polishing a cylinder head face, fly cutting the face is as easy as it gets engineering wise, if they had too high a spindle speed i'm

guessing they got vibration/chatter marks, pretty poor tbh !!

All the best

Never heard of manually polishing a cylinder head face, fly cutting the face is as easy as it gets engineering wise, if they had too high a spindle speed i'm

guessing they got vibration/chatter marks, pretty poor tbh !!

 

All the best

Exactly, and they try go removed the chatter marks with this stupid hand polishing. I was given this information that they did this after I had install the head on the engine:banghead:

Thanks

I had head lift problems a few times at high boost, L19's sorted it though, it had to be torqued down so hard it squashed the head a little in the end. I can't remember the torque settings now.

Reinz make some of the best MLS gaskets in the industry, here's what they say on surface finish:

http://www.victorreinz.com/EN/Service-Downloads/Practical-Information/Multi-layer-Steel-MLS-Cylinder-Head-Gaskets.aspx