Head gasket material? (AFM vs multi layer steel)

[GaryZH]

Hi everyone, I'm currently in the process of replacing the head gasket on my car and noticed there are two different types of gasket materials available on the market and both from reputable brands.

Victor Reinz supplies a head gasket made from a soft composite material marked as "AFM", which kind of reminds me of those old-style asbestos gaskets that were prone to blowing out. From what I’ve found online, it seems to be an advanced fiber composite, but I’m not very familiar with how it performs in real-world use and I haven’t seen much user feedback or long-term experience with it either.

On the other hand, Ajusa offers a traditional Multi-Layer Steel (MLS) head gasket, which matches the OEM gasket originally used in my engine.

Has anyone had experience with the AFM-type head gaskets?
Are there any clear advantages or disadvantages compared to MLS?
I’ve always trusted Victor Reinz, but this material difference is making me a bit hesitant.

Any insights would be greatly appreciated!

 

[clinebarger]

Composite gaskets are more forgiving of block & cylinder head surface imperfections, That's about the only advantage it has over a good MLS gasket.

No all engines are machined for MLS gaskets.

 

[trd1zz]

What car / engine are we talking about here

 

[slacktide_bitog]

Try head gasket sealer first! Bars Leaks HG-1 is good stuff that I can vouch for. Blue Devil Pour-N-Go has been used successfully by many people as well.

Composite gaskets are more forgiving of block & cylinder head surface imperfections, That's about the only advantage it has over a good MLS gasket.

No all engines are machined for MLS gaskets.

I didn't know that!

Fel-Pro has a nice MLS head gasket that claims to be more tolerant of an imperfect surface

 

[ka9mnx]

Fel-Pro is my first and foremost go to for gaskets.

 

[RooflessVW]

I do like Fel-Pro head gaskets

 

[RDY4WAR]

Only use MLS gaskets if you have freshly machined surfaces. If there's any warp more than .002", you run the risk of the MLS gasket not sealing well. It needs a flat surface. The composite gasket is more forgiving in this regard which makes it good for head gasket replacements in the car so you don't have to pull the engine and tear it down to machine the surfaces. (still need to clean it up and remove all of the previous gasket) Composite has it's limits as well with cases of warp bad enough that even it won't seal. In which case, you have to tear it down anyway, and might as well go with MLS at that point.

 

[ka9mnx]

If memory serves me right, and that's dangerous, metal head gaskets are reserved for high performance engines with high compression ratios.

 

[RDY4WAR]

If memory serves me right, and that's dangerous, metal head gaskets are reserved for high performance engines with high compression ratios.

In the old days and classic car / racing circles, yes. They've been more commonplace from OEMs since TGDI became a thing.

 

[ElectroMechanoMan]

As long as the material isn’t the old style rubber/paper composite, you will be fine as long as you don’t have to replace it soon. Otherwise I’d use laminated metal.

 

[GaryZH]

What car / engine are we talking about here

Hi, it's an alfa romeo 156gta with 3.2 busso v6 engine

 

[GaryZH]

Try head gasket sealer first! Bars Leaks HG-1 is good stuff that I can vouch for. Blue Devil Pour-N-Go has been used successfully by many people as well.




I didn't know that!

Fel-Pro has a nice MLS head gasket that claims to be more tolerant of an imperfect surface

Thanks! I'll definitely give it a try on my honda daily, gosh I have so many HG problem this year

 

[GaryZH]

As long as the material isn’t the old style rubber/paper composite, you will be fine as long as you don’t have to replace it soon. Otherwise I’d use laminated metal.

Thanks, I just got back from Victor Reinz. They said the gasket is made from a type of graphite material with metal sandwiched in between. They claim it’s more tolerant than traditional MLS gaskets.

 

[nthach]

Composite head gaskets were a graphite/fiberglass(or asbestos) material with metal fire rings and sealing elements. The new MLS gaskets are all steel with FKM/silicone sealing beads, embossed fire rings and a PTFE/FKM coating overall.

Many modern engines since the 1990s come with MLS as OE.

 

[rijndael]

Many modern engines since the 1990s come with MLS as OE.

Hence the rust jacking that happens with some head gaskets in the north east.

 

[Trav]

You may want to look at the ones from Protoxide. If you have the heads shaved you can get the appropriate thickness.
I have not used them but they have a following for parts for these cars, the fact you can choose the thickness is a big deal in maintaining the CR after head/block work.

https://www.protoxide.eu/en/reinfor...rwqEaOEpUh9hTzNhWnpwB63vRtHPKW2vTwIHG_DBUYa6r

 

[GaryZH]

You may want to look at the ones from Protoxide. If you have the heads shaved you can get the appropriate thickness.
I have not used them but they have a following for parts for these cars, the fact you can choose the thickness is a big deal in maintaining the CR after head/block work.

https://www.protoxide.eu/en/reinfor...rwqEaOEpUh9hTzNhWnpwB63vRtHPKW2vTwIHG_DBUYa6r

Thanks a lot! That would definitely be the way to go for a full engine rebuild in order to keep the CR and timing correctly, but since I’ve only pulled the head off with the block piston and everything else in the bay, I can’t mill the block.