Cylinder head lift during duno

[teddan]

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.

 

Did you have that with your 7675 turbo that I bought from you? I am running the titan headstuds H11 (L19) but the torque it self is not so high according to the instruction 85 ft lbs (Normal arp head studs has 80ft lbs)

Do you remember Jamie which head gasket you where running?

Would be great if you could remember the torque.

 

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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

 

Thanks Chris

Edited August 28, 2016 by teddan (see edit history)

[Digsy]

Just wondering why none of the big-power tuners with money to burn don't invest in a set of Kistler spark plugs and engineer things like this properly before you get anywhere near wrecking an engine? Thumbnail calcs for head bolt cover factor aren't difficult but you do need to know what cylinder pressure you are going to be running (plus the mechanical properties of the bolt, but the bolt supplier should be able to tell you this, and if they can't they shouldn't really be supplying bolts).

 

Incidentally, over torquing a head bolt can be just as bad as under torquing, as all that clamp load still has to be transmitted down the bolt boss and into the flame face. If the surrounding head structure isn't stiff enough then you will just deform the head and/or the cylinder bores. Its also perfectly possible that the head flame face simply isn't stiff enough to stop lifting no matter how hard you nail it down at the corners, unless you fit an exotic seal around the combustion chamber, as CW has already suggested.

 

Regarding flame face surface finish, I've expressed reservations on here before about getting the surface finish right after skimming. Unless you want to pay to take the head to a third party lab to have the surface finish checked independently, I'd be surprised if many machine shops could absolutely guarantee getting the surface finish right. However, most head skims do seem to work. I think the issue here is what is going on inside the combustion chamber and not the surface finish.

[Chris Wilson]

Good post Digsy! The only way to work around casting inadequacies when you get to huge cylinder pressures is something like the nitrogen filled Wills rings. The 7M-GTE predecessor to the 2JZ-GTE engines had an inherent head sealing problem due to bolt placement and head structure. Toyota went to some pains to rid themselves of that devil with the 2JZ's, but they didn't engineer it for 1000BHP cylinder pressure levels

 

This Motec forum post may be of interest:

 

http://www.motec.com/forum/viewtopic.php?f=26&t=575

[and1c]

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

 

That adds a new dimension to your problem.

I would take the head to a better engine machining shop and get the finish checked. Hand polishing flashes up warning signs...

 

Read this it refers to surface finishing and stuff.

 

It may be worth sending an email to WOTM or SP in the USA to see if they have any ideas. Plenty of bigger power supras in the US dont have this issue though with L19s and stock headgasket.

 

http://www.hotrod.com/articles/ctrp-1108-racing-head-gaskets/

[JamieP]

Did you have that with your 7675 turbo that I bought from you? I am running the titan headstuds H11 (L19) but the torque it self is not so high according to the instruction 85 ft lbs (Normal arp head studs has 80ft lbs)

Do you remember Jamie which head gasket you where running?

Would be great if you could remember the torque.

 

- - - Updated - - -

 

 

I've had its with lots of different turbos over the years, yes I did have it with that turbo and I had it on a T67. It was never really power related but down to boost. I cant remember what torque settings we used now but I'm sure is was much more than that. When I went to the the bigger GT42-76 I never had an issue with it.

[Digsy]

This Motec forum post may be of interest:

 

http://www.motec.com/forum/viewtopic.php?f=26&t=575

 

Hmmm. Well if Kistlers still roll in at four figures plus the cost of the DSP then its no surprise that no one outside of OEM world uses them. I thought that AVL came out with a kit aimed at hobbyists and small businesses a few years back?

[Krister]

Too much ignition timing on E85.

 

Detonation with E85 will lift the head. How much timing were you running?

 

Go with the stock headgasket and be subtle with the timing at peak torque. I've experienced that after 1000hp, you will start lifting the head on E85 quite easily with too much timing. Most likely if it wasnt too bad, you just back off the timing 2-3 degrees and the head gasket still seals fine after that.

 

Also remember to re-torque the head after you've heat cycled it.

Edited August 31, 2016 by Krister (see edit history)

[Krister]

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.

 

Don't go with a 2mm head gasket, you will ruin the quench area.

[teddan]

Too much ignition timing on E85.

 

Detonation with E85 will lift the head. How much timing were you running?

 

Go with the stock headgasket and be subtle with the timing at peak torque. I've experienced that after 1000hp, you will start lifting the head on E85 quite easily with too much timing. Most likely if it wasnt too bad, you just back off the timing 2-3 degrees and the head gasket still seals fine after that.

 

Also remember to re-torque the head after you've heat cycled it.

 

True statement. We did not started to adjust the timing when this happend.

 

But it could be that by timing is not correct and giving wrong input from the trigger.

 

The head is for moment at snakefield but he also where looking on the head and then thought that timing was the problem. Did you judge that the timing is to aggressive from the picture I post?

 

 

I how much will the headgasket take? I am aiming around 1200hp.

 

 

Thanks all for your input so far! great!

[Krister]

I am pretty sure Real Street uses the stock head gasket on their RS1600 engine package which is good up to 1600hp.

 

I've ran 1200hp with the stock head gasket. You should be fine.