After reading that PCT pistons in a b17a actually yields a 12.1+ C/R (negative deck height), I want to drop my C/R with a thicker headgasket (only 91 octane here in CA). My plans are to run a .43 cometic headgasket which should drop the C/R to about 11.7. Would the MLS or HP be better for a N/A setup?

thanks
1.7na

couldn't find anything about this with search

 

Now - first of all you need to try harder. Most of the Type R owners try to INCREASE c/r with headgaskets. Which makes you wonder - well who would be the people that are trying to DECREASE c/r on a regular basis - - > FI Forum.

Using the keyword "cometic" I found these in the FI archives:

https://honda-tech.com/zerothread?id=230445
https://honda-tech.com/zerothread?id=526678
https://honda-tech.com/zerothread?id=729193
https://honda-tech.com/zerothread?id=716852
https://honda-tech.com/zerothread?id=700511
https://honda-tech.com/zerothread?id=690861
https://honda-tech.com/zerothread?id=685304
https://honda-tech.com/zerothread?id=682975
https://honda-tech.com/zerothread?id=650764
https://honda-tech.com/zerothread?id=644550
https://honda-tech.com/zerothread?id=645379
https://honda-tech.com/zerothread?id=601595
https://honda-tech.com/zerothread?id=565366
https://honda-tech.com/zerothread?id=558177
https://honda-tech.com/zerothread?id=495635
https://honda-tech.com/zerothread?id=532988
https://honda-tech.com/zerothread?id=502146
https://honda-tech.com/zerothread?id=454401
https://honda-tech.com/zerothread?id=374399
https://honda-tech.com/zerothread?id=252504
https://honda-tech.com/zerothread?id=320985
https://honda-tech.com/zerothread?id=315632
https://honda-tech.com/zerothread?id=282946
https://honda-tech.com/zerothread?id=293735
https://honda-tech.com/zerothread?id=246037
https://honda-tech.com/zerothread?id=206738
https://honda-tech.com/zerothread?id=194153
https://honda-tech.com/zerothread?id=187644
https://honda-tech.com/zerothread?id=172368
https://honda-tech.com/zerothread?id=164965
https://honda-tech.com/zerothread?id=162439
https://honda-tech.com/zerothread?id=144502
https://honda-tech.com/zerothread?id=130446


and that's not the whole list either!

 

Big Phat R

Yes, I know using a thinner gasket will increase C/R. But since I'm in
CA and only get 91, I want to drop my C/R to a safer level. I did this swap about 3 years ago before anybody realized that PCT's had a negative deck height on a b16-17a block. All I wanted to know is which I should use the MLS or HP headgasket for a NA setup. Sorry if this is the wrong forum but it seems that there are more people who knows about NA setups in here and thought they might have more info.

thanks
1.7na

 

is this motor in a Type R?
check with the all motor forum

 

Just yanking your chain. You sure you want 0.43? That's one THIIIICK gasket

Re: cometic

Cometic's MLS (Multi-Layer Steel) Gaskets

These are constructed of two nitrile coated outer embossed spring steel layers with a steel inner layer that provides support to the gasket allowing multiple thicknesses. Cometic gaskets withstand the shearing forces created by aluminum heads on cast iron blocks. Once the gasket takes a torque set, there is no re-torquing required. Less clamping force is required allowing for reduced bore distortion.

Cometic HP Style head gasket
These gaskets have an extra shim around the combustion area to help seal better for cars with turbo, nitrous or supercharger.


Cometic MSL Gasket
Thickness: 0.025”, 0.030”, 0.040”, 0.054”
Thickness: 0.067”, 0.078”
Thickness: 0.098”, 0.120”

Cometic HP Gasket
Thickness: 0.036”, 0.043”, 0.057”

_______________________________

I say the MSL for your purposes....but what do I know?

 

Thanks Big Phat R. That is basically want I wanted to confirm.

Thanks again!
1.7NA