Boost/power limit on Non-oring head/block

[perrytheplatypus157]

Anybody here personally running more than 45 psi on a 64mm+ turbo without O rings in the head/block? I'm currently at 44-46 psi depending on ambient temps on a 6466, but I'm a little afraid of upping the boost for fear of lifting the head. I'd like to see what kind of power I can make and I feel like the limit is within a few more pounds.

Quick info if you don’t want to read my profile:
2.0l
S3’s
Still T3

I understand I could flow more with a T4 but I’d like to stick with my current setup for now. I’ve got other financial goals I need to achieve before I start dumping money back into this car.

 

[97gsxIA]

A wise man once told me:
"Maybe."

I'm sure there's few guys on here that have and do run over 45psi, but they're the same guys who don't mind spending the weekend changing headgaskets (hell I don't). But at that pressure I wouldn't be worrying about the headgasket as much as I would valve float (I don't mind changing HG's). Those beehive kigglys you got with 97lb seat pressure would be reduced down to 52ish... which is playing with fire at the RPM you're going to be at.

I'm sure you could pull it off.. roll the dice, you're call. Just remember it is a dice roll and the chances of hitting double 6's is the same as hitting snake-eyes.

 

[1990TSIAWDTALON]

I have ran up to 44 on my 2L 6 bolt with a 2g head and no orings, but the head is torqued down good!
My son has ran up to 41 lately on his non-oring 7 bolt, also with the head held down more than the factory calls for.

 

[perrytheplatypus157]

Alright, so it wouldn’t be a bad idea to measure spring pressure, and shim them to 110 lbs if possible. This would allow me 50 psi of boost while still maintaining 1.7x the seat pressure. Other than that though, would it seem unreasonable to see 50 lbs on a non ring setup? I can’t imagine I would make any more decent power after 50, especially with such a restrictive hotside.

 

[DSMPT]

IMO, you would probably be able to go a few more pounds. I had been running 45+ psi range for some time before. Was without o-ring, a 67mm turbo, L19 studs, Kiggly high pressure springs without shimming. I didn't have any issues while running less than 50 psi. In my case it started to push the coolant a bit after pulled a couple of times with 52-53 psi. This number would be depending on build quality though.
If you would like to go 50+ psi, as mentioned above, it should be more concerned about springs than lifting the head.

 

[diambo4life]

I think mine was 41-43psi on the GT35R almost 10 years ago.

I have been running an o-ringed head ever since. It sucks pushing coolant after every pull. Now I worry about breaking driveline parts.