Twins and Head Gaskets Oring or Firering???

[moremph]

I have hx40 and s4 on my truck, i have a oringed head and blew a head gasket this weekend. I am wanting to know what are people running for boost pressure with oringed heads and also with firerings.

I also have arp 12mm studs and i am currently running 23 degrees of timing.



I am not sure to go back with oring or to firering it I seen 75psi once and i believe i had about 1/4 throttle left.



Thanks,

Chris

 

[Graphic man]

A lot of guys run 80psi + with just an O-ring



did you do the re-tq a few times after it was installed?



you got 75psi out of an HX40?



Scott

 

[WDimig]

hx 40/S4 bottom tubo in a twin setup, will easily reach 75psi, more if not wastegated, i had ym head blow with fire rings, although the problem was due to improperly surfaced head, fire rings will not 80+ psi if dont right, they need to be retorqued a couple of times whn first installed, and once or twice more after a couple thousand miles, this will ensure you no problems with your head in the future.



wes

 

[TravisG]

When did you blow it? On the way home Saturday. Sorry to hear about it dude.

 

[moremph]

Yeah on the way home sunday about 40 miles from home. Not too bad just wanting to fix it so it won't happen again. i need to wastegate the s4 or something. I had plenty of throttle left when i hit 75+.



Chris

 

[AFarmer]

You really should be running an external wg like a tial or something so you can do a little tuning on those twins. I usually make somewhere between 65 and 75 with mine and have never had a problem with my gasket. A good resurface and oring job and several retorques will work just fine.

 

[wildmanben]

I got mine studded, o-ringed, and retorqed 4 times to 125. So that will hold 80psi?