Pro Stock John

iTrader: (34)

I run the MLS 6.0 head gaskets, got the idea from Harlan, my longblock is similar to his setup from a year ago.

1dirtyZ

iTrader: (1)

thanks for the info, any idea on the thickness of the MLS gaskets?

Billiumss

iTrader: (11)

I'd like to know too...

MYTURBOT/A

The rad cap is suppose to be under pressure if it isn't the cooling system won't work right. FYI the 6.0 head gasket thickness is .055 according to GM.

MelloYellow

Just had this same problem with Cometic MLS's on my new motor.
They are off and will never touch my car again.

Also had an earlier Cometic failure after 1 year on motor.
They just don't always seal up well.

Am using GM MLS from now on.

MYTURBOT/A

When I was getting ready to do my head swap i talked to cometic and they said themselves that they were having sealing problems with there HP gaskets and were working to resolve it. So i went with the stock MLS.

MelloYellow

Oops, sorry for saying HP (edited).

My problems were with the Cometic MLS also.
I threw my HP in the trash and they never went on either engine.

Even the Cometic non-HP series have been a nightmare for us lately.
I've never heard of a problem with the GM MLS tho.

1point3liter

Off topic of the lifting heads...

If you're hearing ticking up top (possibly detonation), have you tried running race gas to see if it clears up?

stealth

We've got a master's degree in lifting heads off an LS1. The first and most obvious symptom would be blowing coolant into, and out of, the collant reservoir, and perhaps finding coolant splatter in the engine compartment.

MelloYellow

Pressurized Coolant, ie: Coolant Loss, Blowing into Coolant Reservoir, Boiling Radiator Cap, Coolant out exhaust, Popping Freeze Plugs out of your heads (fun).