legacycentral bbs

I'm probably going to pull the motor this weekend. I know I've got a leaking valve issue and need to take care of that.

My question is mainly around head studs and gaskets.

Did some searching and found the thread regarding the correct ARP stud part # 260-4702 for the stock ej22t motor. The remaining question I have on the head studs is regarding torque procedure. I'm guessing since I'm not stretching the studs, I don't necessarily need to follow the crazy Subaru procedure. Am I wrong in that assumption? I have had a chance to search NASIOC yet, but if there's info over there and you have a link, that would be appreciated.

Head gaskets, I see two main options, stock or Cometic.

I had heard/read a comment regarding the Cometic head gasket and that they had seen failures with it, and as a result only use Cosworth head gaskets. Did a little research on the Cosworth head gaskets and found that they don't list one with the correct bore size. Not that they probably couldn't make one......but mainly just interested in any feedback regarding that comment.

Now back to the stock gasket vs. the Cometic gasket. Any pros or cons for either. Obviously the price is going to be more for the Cometic, about $20 per gasket. That's not a huge issue, I'm more interested in any technical comments, pros or cons. The part # I found for the Cometic gasket is C4263-051.

Thanks

ARP says to torque them down in three steps, ending up at 85 ft-lb.




As far as the head gasket thing, its a horse apiece. I had the old turbo up to 28 psi in the winter with the 22T headgasket without issue. The graphite based gasket is probably a little more forgiving on surfaces that are not freshly machined.

I'm using the .051" Cometics now, with a coating of the copper spray gasket on them. We'll see how they do. Derek hasn't had an issue with his Cometics yet.

Thanks for the info Dan.

The heads will likely be machined due to them getting reworked to fix the valve. However the block will not.

the arp head bolts for the ej22t i have no clue, but i did use them for my dohc and we set them like the crazy subaru specs.

for the head gasket, i used lots of factory ones and they work perfect just what 93forestpearl siad, then i started useing the cometic ones on my dohc set up's ( i really dont know why, lol shine new parts i guess ) but they last long, i had a set on my second ej22t wit ej20g heads and i put 400,000kms of pure beat down, if that motor didnt have a crazy ticking noise i would still be useing it.

I just installed a set of the ARP studs on the STi motor, and read through the whole NASIOC thread...I followed ARP's instructions and torqued them to 85 ft-lbs.

I've seen far too many people have problems with Cometic head gaskets regardless of who does the machine work. The OEM metal gaskets seem to hold over 20 psi with no issues at all.

If I had the option to use OEM STi headgaskets, I would. On an EJ22T, that isn't really an option with the piston protrusion above the deck surface.

93forestpearl wrote:If I had the option to use OEM STi headgaskets, I would. On an EJ22T, that isn't really an option with the piston protrusion above the deck surface.

Very true. For the record, I was more making a point against Cometics than making a point for any particular OEM gasket.

ive always read good things about oem and bad about aftermarket., are you on stock heads with that td05?

i find nothing wrong with those head gaskets, i put them to the test of a beat down and they work perfect.

i think its user error that comes in to play, and my test are real live test, canadian winters and hot summers, with tracking the car and q mile also. i would go twice a week most of the time becuse i live 15min away from a track.

but in the end, do what you like lol.

I know many Subaru techs which replace the last step of the Subaru sequence with 75 foot pounds or so.

I just looked at the ARP procedure and its almost exactly the same as the way I put heads on lol

As for Cosworth HG's....I have called them before and they told me they don't and will not make a 98mm bore HG. They only make them for 2.0L and 2.5L motors.

I am also trying to decide on a HG for my build and was going to go with Cometic, but you guys are making me second guess myself.

Whats the thickness of a stock ej22t compressed HG?

Thanks for the comments guys.

I'll have to do a little more research on the cometic gaskets. Haven't read through the stuff on NASIOC. I also need to read ARP's procedure. Is that on nasioc, or ARP's website?


Other thing I was going to add is that I did not follow the factory procedure for torquing the heads. I had used the procedure CCR engines uses. I don't recall exactly what it is though...

CCR procedure is...All bolts in order to 25ftlbs, then all to 50lbs then the center 2 to 80ftlbs and corners to 72ftlbs....in order.