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Discussion Starter #1
Supposedly the the MLS z6 gaskets fit an DOHC ZC, allowing you to have a decent MLS gasket with out paying Cometic prices.

Has any one fitted one and can tell me what modifications were needed or adjustments ?

Thanks
 

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1988 Honda CRX
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For one, the head bolt holes might be to small.

I am 99% sure they don't fit.
 

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I tried one years ago u have to open all the hole to recieve 11mm bolts and move to holes outwards, it worked great but we forgot to shave down the dowel pins and it started leaking coolant out the front of the engine.



 

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Discussion Starter #7
Thanks for the pictures, your head and gasket look different to mine, here is my input.


Here it aligns pretty good, 2 coolant holes are blocked on the right water jackets, these could be carefully drilled open though


And top right headstud needs opening with a dremel.






Here we can see the 2 bottom oil ways, the gasket does not clear them so oil would leak out to the outside of the engine.

Overall I don't think a z6 gasket can be used.
 

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Discussion Starter #8
Just an update, I have been talking to someone who did use a z6 gasket with his DOHC ZC.

To get around the 2 gap at the front he sealed it with some high temp sealant (I imagine Hondabond would work) I think this would work as it is not a pressured area, just a gravity oil drip. He also filed the top right stud hole.

Overall I can see this working but it seems a little bit bodged to me, I'm going to use the stock gasket for now and If I suffer from head gasket reliability I will then look into the mls gasket at a later date.

Also with skimmed heads you will need to file down the dowels.

Hope this info is useful for anyone who can't get on with the standard gasket (maybe useful to turbo guys ?)
 

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Discussion Starter #10
I've only seen cometic for the d16a9, and of the 3 that I know have been used, they all leaked. Even on Nasp engines.
Have you got a link ? And I think the d16a1 is different to the a9.
 

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I've only seen cometic for the d16a9, and of the 3 that I know have been used, they all leaked. Even on Nasp engines.
Have you got a link ? And I think the d16a1 is different to the a9.
It's not, DOHC ZC OEM Head gasket is the 88-89 Integra (USDM). If their head gaskets leaked, then they had other problems you didn't know about.

Right in the middle, there is the DOHC ZC

Race Engineering, Inc - Gaskets-Cometic MLS
 

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I've had the same experience with Cometics on the ZC as well as a few friends.

There's not "good" way to redrill the dowel location on the Z6 gasket so it can be used with the ZC so I would have to say no it won't work.

I've never had issues with the stock gasket even under boost.
 

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I've had the same experience with Cometics on the ZC as well as a few friends.

There's not "good" way to redrill the dowel location on the Z6 gasket so it can be used with the ZC so I would have to say no it won't work.

I've never had issues with the stock gasket even under boost.
Did they have the block/head resurfaced to a fine level? The stock D16A1 head gaskets are graphite and conform to rougher surfaces better, while the MLS need a finer surface to seal properly. If you install correctly you shouldn't have problems, I've used them the correct way on maybe 5-10 engines without a single issue. I don't know what you guys are doing wrong :thinking:
 

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500+HP isn't so good with them. Nearly every high HP DOHC ZC has used the now defunct HKS gasket or the Cometic.

For anything else, I will just spray a gasket with copper gasket spray and rock on without thinking twice.
 

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I use the Cometic on DOHC D builds. Install properly (correct surface finish, clean, etc) and you won't have a problem.
 

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Discussion Starter #16
Thanks for the help. I'll use the stock one on this bottom end while I rebuild a different bottom end and get that machined flat for a cometic. :TU:
 

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For Cometic or OEM, It needs to be flat. The difference is smooth.

The thin layer metal gaskets NEED a very smooth and flat surface both sides.

The OEM composite gaskets NEED a slightly rough or grainy and flat surface both sides. They are a little more forgiving of not quite flat, but if you are going to push them hard, the surface still needs to be dead flat for optimum performance.
 

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does anyone know if i do a d16z6 head swap on a d16y7 block will i need to swap obd harness also :awais:
What I do know is you should start your own thread instead of jacking someone elses
 
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