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So for the 954 on partzilla they list three different head gasket part numbers.
One costs a bit more. Anyone know what the differences are there by chance?

Also, when actually installing these, do folks install them dry with no added sealer? The manual mentions nothing of sealer. Some folks I see mention the permatex copper spray. etc.
I think when I did a copper gasket on an F2 I didn't use anything but it's been like 13yrs or something since then. ; )
 

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Not sure why the different part numbers. Cometic makes gaskets for these in different thicknesses so that may e it. The different thickness will give you slightly different compression ratio. The gasket they make is M.L.S. (multi layer steel). I have not put any on these ikes but am very familiar with them for my turbo Mustang! You need a certain RA on the surface finish for them to work properly. It needs to be very smooth. Some people say to use the copper spray, I have put on a half dozen pairs and not used the spray. Not using the spray is not why I have went through so many gaskets! Some people have a problem with them leaking coolant without spray, I have not had this problem. I do however make sure the surface is EXTREMELY clean before install. Use a white terry towel and brakeleen. Spray the brekeleen on the towel and wipe till your towel comes up not black. You can use the spray for peace of mind as I have heard 0 bad results from it. Good luck with figuring out the part numbers, or you could just call Cometic and see what they say.


http://www.cometic.com/contact.aspx
 

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So for the 954 on partzilla they list three different head gasket part numbers.
One costs a bit more. Anyone know what the differences are there by chance?

Also, when actually installing these, do folks install them dry with no added sealer? The manual mentions nothing of sealer. Some folks I see mention the permatex copper spray. etc.
I think when I did a copper gasket on an F2 I didn't use anything but it's been like 13yrs or something since then. ; )

Don't know why they list numerous gaskets, possibly over-size to suit the 0.25mm pistons?
751 is the 954 suffix code, 003 is 929.
OEM gaskets are coated already - put them on dry.
You would have to follow the directions included with aftermarket gaskets.
 

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Would a marginally smaller head gasket make for a valve strike? I wouldn't assume that the valves are getting that close to the pistons, but I was thinking that if you put on a slightly thinner head-gasket it would give you a very slight bump in C.R. and possibly power?
 

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Would a marginally smaller head gasket make for a valve strike? I wouldn't assume that the valves are getting that close to the pistons, but I was thinking that if you put on a slightly thinner head-gasket it would give you a very slight bump in C.R. and possibly power?
That is true, a thinner gasket will bump compression. I doubt it would cause piston to valve contact but the only way to know for sure is to clay the piston and check the clearance.

Blade, many if not all of the MLS style gaskets are coated with a Viton type material and still some people swear by copper spray.
 

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Would a marginally smaller head gasket make for a valve strike? I wouldn't assume that the valves are getting that close to the pistons, but I was thinking that if you put on a slightly thinner head-gasket it would give you a very slight bump in C.R. and possibly power?

No, it won't cause contact.
Yes, you would get a slight increase in compression, but I doubt there'd be any measureable improvement in power. On engines with seperate barrels you can remove the base gasket and split the multi-layer head gasket and make a noticeable difference. I took 0.55mm out of my '98 750 this way. You will also see an increase in temperature though.
 
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