How much will a MLS head gasket compress?

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How much will a MLS head gasket compress?

Post by SilverXJ »

I measured the new MP gasket at .041" uncompressed. How much can I expect it to compress? One figure I got was .038"

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Re: How much will a MLS head gasket compress?

Post by Exos »

I'd like to know this too... I did not measure mine yet, but I assume it is the same as yours (P4529242).

Isn't it supposed to be 0.043 COMPRESSED?
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Re: How much will a MLS head gasket compress?

Post by SilverXJ »

It can't be .043" compressed.. it only measures .041" uncompressed. Perhaps that measurement was for the old composite gasket.
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Re: How much will a MLS head gasket compress?

Post by Alex22 »

Are you measuring the gasket with a micrometer or a pair of calipers? and have you checked them with gauge blocks recently?
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Re: How much will a MLS head gasket compress?

Post by SilverXJ »

Calipers... and what are gauge blocks? If they are for checking calibration, then I check them against another pair weekly.
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Re: How much will a MLS head gasket compress?

Post by Exos »

I will measure mine with a calibrated micrometer tomorrow or Tuesday and let you guys know.
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Re: How much will a MLS head gasket compress?

Post by rradford9 »

Mine measured .038 when I measured the metal section with my digital calipers...How much can/do the metal layers compress? I'd assume very little, like maybe a couple of thousandths.
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Re: How much will a MLS head gasket compress?

Post by Exos »

Micrometer at work is out for calibration...

I did measure it with an uncalibrated vernier caliper, so it's most likely not accurate. My result is : 0.0475" in the non-metal section. The gasket came with kit P4529245.

It's not MLS I think, it sure don't look like the pics on other threads about MLS Vitor-Reinz. So I guess I'm out to buy another head gasket :oops:
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Re: How much will a MLS head gasket compress?

Post by SilverXJ »

You must have the older version of the MP gasket. The old one I have did measure thicker than their new MLS. I'll have to take pics of the old vs new one.

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Re: How much will a MLS head gasket compress?

Post by Exos »

I'm not sure what P/N I have to look for now.... 53010587AA? P4529242? Other?


edit : or I could keep this one if it's actually 0.047 ...
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Re: How much will a MLS head gasket compress?

Post by SilverXJ »

The new and old style MP headgasket is the same number. The old one is said to compress to .043"
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Re: How much will a MLS head gasket compress?

Post by Exos »

Did you buy the gaket set P4529245 or head gasket alone P4529242?

What about 53010587AA, what's the difference with P4529242? From what I know, P means Mopar performance, but the 53010587AA looks like it's EOM, MLS and thinner....?? I don't want to have to buy more than one more!! :doh:
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Re: How much will a MLS head gasket compress?

Post by SilverXJ »

The one I ordered is P4529242, which is the Mopar Performance one, alone. The stock size, .051" is 53020754AB. The 53010587AA appears to be a stock MLS replacement.
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Re: How much will a MLS head gasket compress?

Post by Exos »

Ok, so the P4529242 is NOT included in the P4529245 set, like I believed. P4529242 is MLS, right? I guess I'll order it and have two choices of thickness. What I don't get is the one I got from the set is 0.048" uncompressed, measured in the thinnest part, and not 0.051. Maybe it's a Felpro. Or my caliper could be wrong.
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Re: How much will a MLS head gasket compress?

Post by Alex22 »

The flat sections of a MLS gasket should only compress enough to get the air space out and then maybe a few tenths. If the gasket has raised sections those will compress to just about the thickness of the flat sections. This threw off once when we were checking piston to valve clearance with a new MLS gasket and the head was only torqued down by hand. Once it was torqued to spec the valves got a lot close to the piston. IIRC about .020, we had to machine the pistons to get the clearance back.
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