rodent

iTrader: (35)

I went with OEM Evo 9, 5 layer, bored out to spec from Buschur. Its the only gasket I feel safe using without o-ringing the block/head running more than 40psi. I'm glad someone started to make these available again. For me to do it, it requires a trashed 2.4 block where they bore it out more than 87mm and a 4g6x torque plate at a good machine shop.

The Cometic gave out in all cylinders and was pushing coolant. Last pass I did at Bandimere was the worse. I actually have deep scars in the head from the HG failing. Luckily the head can be saved from re-surface.

JohnBradley

iTrader: (30)

The OEM five layer will torch around 38psi from experience. The issue is more likely head and deck than headgasket. Prep is everything, then new studs, a tune that isnt pushing the envelope, etc. I ran no O-ring and 40psi on a Cometic, Atif ran O-ringed and a 7175 at mid 40s so I know that a cometic will work.

NSDQ

iTrader: (1)

Nevermind.

rodent

iTrader: (35)

Which OEM HG is everyone running 40+ psi then? The 3 layer Evo 8?

My head was surfaced at the best head shop here in Denver and very smooth. Block was also surfaced properly and very smooth. Before this motor, my last 2.0 held 43psi no problem with the OEM gasket but I'm not sure if it was the 8 or 9 gasket.

This is the head following the Cometic failure.[/URL]
I circled the 4 areas where it let go. The spot on the right was the worst.

Mauricio Evo IV

iTrader: (1)

Yesterday I blow my cometic head gasket, in my 2.1 destroke 4g64 with only 32-33 psi with a 6266 turbo.
I´m looking a Cosworthhd or better choice, and OEM like you said.

The question is: Where can I buy it or with who can I contact for made the deal...

I will preciate your help man!

rodent

iTrader: (35)

Contact Nick at Buschur. I actually bought 2 bored out OEM gaskets but I may sell one for what I paid if anyone needs one quicker.

tscompusa

iTrader: (31)

I bought three of the OEM modified for my customers. I run the Cosworth FSL in my 2.4 with 87mm bore. I've had it up to 810whp + around 38psi and no issues.

I'll probably push it close to 900 this year to get a really fast MPH.

I wont touch the cosworth HG as long as it does me good. I am also Oring'ed with the head.

That seems to help a lot when you begin to really turn the boost up.

JohnBradley

iTrader: (30)

A 2.0L on an OE headgasket is fine. A 2.4 on a bored headgasket can be completely different story.

Something in the combo and/or tune wasnt right and the car had migrated past knock to pre-ignition. See how the space between the intake valves has no carbon and the outside edges of the valves are clean? The cylinder on the end, appears to be #1, even has a torch mark to the left of the sparkplug.

Again, knowing how far we have pushed the Cometic, I dont think this was just a gasket issue.

Aaron

rodent

iTrader: (35)

Thanks Tom!

Trust me, the tune actually on the conservative side and was done by someone who knows what he's doing.

How do you explain others blowing Cometic? Most everyone that has pushed a good amount of HP, hates them for not holding up.

Macaroni

iTrader: (9)

Bumping an old thread:

I've blown out my cosworth on my 10.5:1 2.1L within probably 15-20 pulls. Non o-ringed.

shmagi

using cometic 1.3mm on 10.5:1 30psi

2006GSR

iTrader: (3)

2.4 regular rod. 9.5cr. Non oringed. 28 psi. 700 whp 6765. Je proseal head gasket. Roughly one k miles. Gets beaten every time I drive it.