MLS Gasket: Mitsu or Cometic?

[1sickgst]

Hello all. I'll be upgrading to an EVO III 16G later at the end of the summer. I'll be including supporting fuel mods as well. I don't plan on running a huge amount of boost, just enough for a fun, dependable daily driver. I'll go ahead and change the head gasket w/ ARP's as well. My question is, which brand MLS gasket should I go with? Mitsu or Cometic? I've heard lots on both. I'm just curious what to run with my setup. Thanks in advance for the help.

 

[MyBlack94GST]

There's a big difference between resurfacing for an MLS and resurfacing for a stock composite HG.

 

[GVR4592]

Not really, it was done a few weeks ago, but he had assembled it with a felpro felt gasket and it started to push and overheated a few times...i was just informed of this as of my last post, i called him... I didnt pay much atention to the fact becuase when i told him to have it re surfaced, he said it was...meaning it was resurfaced pre headgasket failure and the events that it overheated, on more than one occasion. I just took his word for it, thats where i failed. regardless, its due to the fct that the suface is obviously out of spec. But still, when it goes back together after it gets cut and i polish the surface, its going to be re assembled with a regular Cometic.

So you're admitting you installed it incorrectly, that makes all of your claims against the mls gasket's pointless.

 

[overdoseheroin]

So you're admitting you installed it incorrectly, that makes all of your claims against the mls gasket's pointless.

Sure Johnny Cochran, but thats ONE instance, i can think of another handful of accounts other than mine that had problems, but arguing with you is like arguing with the gold medalist of the special olympics so ill stop trying.

 

[dsm-onster]

It's so easy to contaminate the surfaces before install of the head gasket. Even touching the surfaces w/ your hand COULD contaminate enough to cause an MLS to fail.

If even only one person has the gasket installed and it seals, then the ones that are failing are doing something wrong. Come one. It's a metal head gasket. Considering the capital that Mitsubishi can play with, why would their manufacturing process be so botched as not to have consistant head gasket quality? SO VERY MANY performance shops and VERY high horsepower cars run the Mitsu MLS gasket. I can think of 7 450+ whp setups off the top of my head right now.

Doesn't the WRC evos run an MLS headgasket (I don't know that one)?

 

[overdoseheroin]

It's so easy to contaminate the surfaces before install of the head gasket. Even touching the surfaces w/ your hand COULD contaminate enough to cause an MLS to fail.

If even only one person has the gasket installed and it seals, then the ones that are failing are doing something wrong. Come one. It's a metal head gasket. Considering the capital that Mitsubishi can play with, why would their manufacturing process be so botched as not to have consistant head gasket quality? SO VERY MANY performance shops and VERY high horsepower cars run the Mitsu MLS gasket. I can think of 7 450+ whp setups off the top of my head right now.

Doesn't the WRC evos run an MLS headgasket (I don't know that one)?

The only point i was making was that regardless of the quality of the prep, if there was any done at all (other that the surfaces being decked), 9 times out of 10 the cometic gasket worked better overall over the Mitsu one, for me at least. This only allpies to the regular cometic, i have used a few cometic hp gaskets and they were garbage. Im stickin to my guns and going to continue using the regular cometic gaskets.

 

[TSIMonsteR]

So, if I grab some ARPs and an OEM Mitsu Gasket, I can just slap em on without machine work? (car has never overheated or anything)But with an MLS, I would have to get the block decked and polished as well as resurfacing the head and polishing it too? How much power do you thing the OEM Gasket and ARPs will hold? I am on a budget and if I could get by with an OEM, that would be sweet.

 

[GVR4592]

Sure Johnny Cochran, but thats ONE instance, i can think of another handful of accounts other than mine that had problems, but arguing with you is like arguing with the gold medalist of the special olympics so ill stop trying.

You're right, there's no point in arguing with me when you can't tell the difference between a cylinder head that has been resurfaced and one that hasn't.

 

[1sickgst]

To the OP, are you getting your head & block resurfaced before you are installing the new MLS gasket? I believe you will probably have sealing issues with either of these gaskets if you don't. If this is incorrect & one does normally work without a resurface, I too would like to know as I've been holding off swapping to a MLS gasket as I didn't want to pull the motor to get both surfaces refinished, just for a head gasket. If I could get away with just the head being resurfaced, that would be fine.

Another option is ARP studs with a stock gasket. This has been proven many times to hold a good amount of boost & is sorta a safety factor as if you have a bad tune & end up with lot of knock you will pop the gasket, instead of something more import. I know lots who don't have problem with 25psi on this combo & have heard of numerous who have run more. I've run 22 psi on it without any issues, for a couple summers.

So, do you think I would be OK with with just a regular stock HG w/ ARP's? My goal, ultimately, would be 350-400hp. That won't be anytime soon, mind you, and I do plan on upgrading to possibly a 50 trim or something similar to get me to that HP whenever I do a 6 bolt swap. But that won't be for another year or two. This current upcoming summer project will just get my fuel supply in check for future mods and some more boost for the time being. So, now I'm mixed on using an MLS altogether. I want it to seal, of course, but I can't be without the car for too long as it's the only one I have to drive and I have a 45min commute to work. If I have to get the block surfaced as well, then that's added time.

 

[RedTurboEclipse]

The wiseman got you there. I'm sure he wanted all the variables out for everybody to see before they start accepting claims of mitsu hg being bad by one person/or a small few compared to a greater amount of the population who have used them with no problems.

 

[squeak104]

I don't fully agree with the full mirror finish. My 160,000 mile old block wasn't decked nor polished, and my head was surfaced at about 152,000 when we assembled the engine with a cometic headgasket with arps. When the engine had about 150 miles on it, it overheated big time and after about 10,000 miles now, I still haven't had any problems with it. Even had a leak down test done when it was about 2000 miles along. All cylinders 5% leakdown.

My personal experience though. Everyone has their own.

 

[dsm-onster]

So, do you think I would be OK with with just a regular stock HG w/ ARP's? My goal, ultimately, would be 350-400hp. That won't be anytime soon, mind you, and I do plan on upgrading to possibly a 50 trim or something similar to get me to that HP whenever I do a 6 bolt swap. But that won't be for another year or two. This current upcoming summer project will just get my fuel supply in check for future mods and some more boost for the time being. So, now I'm mixed on using an MLS altogether. I want it to seal, of course, but I can't be without the car for too long as it's the only one I have to drive and I have a 45min commute to work. If I have to get the block surfaced as well, then that's added time.

I run the stock head gasket w/ arps torqued 10 ft-lbs over the proper torque w/ 30 wt. oil. I stepped the torque sequence and re-torqued after 5 heat cycles. I boost to 30 psi w/a glod tune. It WILL be more finicky. I've popped a head gasket w/ 5 counts of knock on my scanmaster.

I ran all last year 30 psi and water injection w/ 60-1 and t3 stage 3 turbine in a BEP housing, w/ FP cams, a good sized fmic, and 3 inch exhaust. I logged 52 lbs/min minutes before my turbo ate itself. BUT, it's not a reliable setup. As I said, it gets finicky at this level. You're probably ok runing jsut arp studs w/ a 400hp goal. Try it out.