HKS MHG vs. Cometic

[topgear]

last time did have a BHG (caused by detonation) on a HKS 1.2mm with 472whp.
Fixed the problem that caused detonation and going for a 600whp and not shure what to use, have this HKS 1.2mm and 3.0mm Cometic
which is better for the job ?

 

[Zumtizzle]

both will yield different compression ratios.

As far as i know, both are like the HKS Stopper.

 

[IJ.]

The Stopper is all on it's own no other MHG is like it

 

[Zumtizzle]

Scratch what i said.

If you're going for big boost HKS Stopper or bust.

 

[IJ.]

HKS Bead and the Cometic are much the same thing

 

[Zumtizzle]

http://www.supracentral.com/index.php?option=com_content&task=view&id=88&Itemid=42

Okay, No wonder the Cometic Head Gasket is Lint and buttons (Pricewise) compared to the Stopper.

 

[IJ.]

But having said all that the Stopper can still be blown if you try hard enough

 

[Zumtizzle]

Well our Estonian friend here can decide.

Topgear: Just make sure you read the link i've provided and calculate your base compression ratio, and decide.

 

[GrimJack]

In my experience, HKS is much tougher than Cometic. I've blown a Cometic without causing any damage to the internals... and I've blown apart some pistons trying to kill an HKS. So, it looks as if:

HKS > Stock Toyota pistons > Cometic.

 

[suprabad]

In my experience, HKS is much tougher than Cometic. I've blown a Cometic without causing any damage to the internals... and I've blown apart some pistons trying to kill an HKS. So, it looks as if:

HKS > Stock Toyota pistons > Cometic.

I'd agree with that, but the Cometic is a pretty decent HG.

Hey Grim...How much boost were you pushing when you blew the Cometic, or was it something else that contributed to the BHG?

Given a decent tune and stock compression, how much boost do you think the cometic can handle? I've known of people running 17 or 18 lbs of boost on them with no problems (as far as I could tell).

Reason I ask is I'm currently running the Cometic with good results, but I'm not pushing huge boost (91 octane is about all you can get in SoCal). Kinda limits what one can do without detonating...and race gas on my dd is not going to happen.

 

[IJ.]

I ran 30psi on a cometic no problems at all until I leaned it out and ran out of IC capacity during a long uphill pull.

I've also popped a couple of Stoppers during fuel system development
(1 when I blew the intake up between 3 cylinders)

 

[GrimJack]

I'm reasonably certain that it was heat that blew the Cometic. I lost a coolant line, then lost my coolant, and the engine compartment was REALLY hot. When I pulled the Cometic, it was snapped in between all the cylinders. I put another HKS back in and it's been running fine ever since.

 

[topgear]

going to use HKS
from now on I`m afraid of using Cometic
didnt thought to buy stopper:aigo:
the reason of using 1.2mm HKS is allso to have good pull while boost lag (using gt40 turbo)

thanks to all of you for advices

 

[Poodles]

Cometic is fine, but the Stopper is in a whole nother ballpark...

 

[jdub]

the reason of using 1.2mm HKS is allso to have good pull while boost lag (using gt40 turbo)

Ummm...if you raise cylinder compression with a thinner MHG and you run high boost = BOOM!

I would stay with stock thickness (accounting for material removed from the block/head decks).

Cometic makes a good MHG...it's all in the prep and torquing it down correctly. The Stopper is the best though.

 

[topgear]

472whp with only 1,1bar

 

[jdub]

472whp with only 1,1bar

And the point is?

 

[1-2clutch-u]

+1 for Cometic. i love mine. i still look at pics of it lol

 

[topgear]

So,
I had HKS 1,2mm and had 520whp, then had fuel problems and engine gone.
Got new one, bought titan motorsport 2.0mm hg and blew it in a week, changed it to 2.0mm hks bead
now it is 2 years since then, car is still in everyday use, has 505whp map, still working like swits clock.

 

[suprarich]

I have motors over 1000 hp on both the cometic and the hks gaskets with out problems. It is all in the prep and tune.