dropping in a new cylinder head this weekend, wasnt sure on what head gasket to get, i bought an LCE .51” MLS head gasket but now im worried since i am not getting my block decked, if its gonna be a problem. just dont have time to do so. dont know if i could get away with it or do i have to buy a regular graphite HG to get away with not decking the block. never used a MLS and my head isnt off yet so im not sure how my block looks. according to lce “

The spec is RA of 8-15
Ra is Roughness Average, 8-15 is microns per inch.
Just make sure you have this on block and head, as factory spec for composite can be 30-60 RA
which will not work with this gasket.”

Dont know if i should ditch the mls and return it since i am not getting my block decked, thoughts on this?

 

In your situation, I would return the MLS head gasket and use a Genuine Toyota head gasket.

If you were going to get the block and head machined to the proper RA for the MLS head gasket, I would probably go with the MLS head gasket.

I think it would be too big of a risk putting an MLS head gasket that hasn't been machined to the proper RA.