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.

 

[TSG59_Steve]

I'm running mitsu, so far, so good. (500 miles)

 

[95blackGsTurbo]

I've been running Cometic for 8500 miles on 21 daily and lots of 28 track boost and haven't had any problems.

 

[mjboehm]

i have a mitsu 4 layer metal head gasket with arp stud on my stroker motor and haven't had any problems

 

[1sickgst]

I thought I would get mixed results. Another question, and I know I've read countless threads on this. Did you spray your MLS gasket?

 

[SlickGSX]

I run a Cometic because thats what my engine builder wanted to use, I had heard about issues with the Cometic and deck + head surface finishes but haven't had any issues yet(2000miles).

 

[99gst_racer]

You could also consider the Felpro MLS. Though more expensive than the other two, it's proving to work quite well on Jake Montgomery's car.

 

[daren_p]

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.

 

[TRBOBLU]

I ran a cometic and I was not happy with the results I got. Ive ran a couple Mitsu MLS gaskets and never had an issue. I also use no sealant or spray when I install them.

 

[marcmsj]

I've been running the stock mitsu MLS gasket with ARP stud (50,000+ miles) and boosted 27psi as of lately, with no issues.

Building a new motor but the stock gasket and ARP setup hasn't let me down.

 

[1sickgst]

I definitely plan on getting the head resurfaced. In the 3+ years that I've had the car, it's never heated up on me. So, I'm assuming the block will be OK. I will get it checked though, just in case. So far, I'm leaning towards the Mitsu gasket. Thanks again all.

 

[spooled_u]

I like the mitsu 4 layer ...

 

[Nanan]

I have put 40k miles on a Mitsu MLS and it never leaked and I once spiked 35ish psi when my EBC popped a fuse.

 

[GVR4592]

Just resurfacing the head usually won't work and that's why a lot of people have issues. Most machinist's don't leave the surface smooth enough for a mls gasket, it has to be like glass or it won't seal.

 

[overdoseheroin]

I have NEVER had good luck w/ Mitsu gaskets...every application (both head and block were decked) they pushed coolant unless o ringed. Cometic gaskets have never given me any issues. I usually throw a thin coat of copper spray on both sides, i dont get too crazy with it though.

 

[GVR4592]

I have NEVER had good luck w/ Mitsu gaskets...every application (both head and block were decked) they pushed coolant unless o ringed. Cometic gaskets have never given me any issues. I usually throw a thin coat of copper spray on both sides, i dont get too crazy with it though.

That's most likely due to installation, if it's done right it won't leak.

 

[dsm-onster]

Yea, there are just too many successes w/ the Mitsu MLS head gasket to excuse it as being a bad gasket. Considering torque sequence values and surface finishing, it seams that ALL metal head gaskets are succeptible . . . or finicky to sealing procedures. That's just life runing alot of power that NEEDs such a setup.

This leads to my question. 1sickgst, do you think you need a mls headgasket to run an evo3 16g to it's limit?

 

[TSIMonsteR]

So you guys are telling me, that in order to switch to an MLS, I have to have my block and head resurfaced? That sucks. Looks like it is OEM and ARPs for me then.

 

[overdoseheroin]

That's most likely due to installation, if it's done right it won't leak.

Not likely, and im not the only one that i have seen have issues.

 

[dsm-onster]

overdoseheroin, take a look at this thread running now if you could: metal head gasket prep.

Do you have a mirror finish? Why are you having so much problems? Many others don't. I forgot, but what gasket are you using now?

 

[overdoseheroin]

overdoseheroin, take a look at this thread running now if you could: metal head gasket prep.

Do you have a mirror finish? Why are you having so much problems? Many others don't. I forgot, but what gasket are you using now?

I dont, but i have told others that i have done work on to have that done after finding out about it a while back. I have only had one mitsu gasket not push coolant, another was with an o ringed head. I currently have the cometic, and every time i have used one or used it on a car i was putting together worked flawlessly. I just prefer the cometic gaskets because i have never had any issues with them. Not sayng mitsu mls gaskets arent good, they just dont like me.

 

[GVR4592]

Not likely, and im not the only one that i have seen have issues.

I can almost guarantee that you didn't install it correctly. Why don't you explain what you did step by step.

 

[overdoseheroin]

I can almost guarantee that you didn't install it correctly. Why don't you explain what you did step by step.

Wow...its little elemetary to have to explain how to install a headgasket...but i will say that i just talked the kid that i did the most recent install and i was under the impression that he had decked the head...he didnt, so that would be the reason for that. Im not going to get into an argument over how i installed it because itis the correct way...i think after 7 years of building these cars i think i would have aquired the knowledge to correctly install a hg.

 

[GVR4592]

Wow...its little elemetary to have to explain how to install a headgasket...but i will say that i just talked the kid that i did the most recent install and i was under the impression that he had decked the head...he didnt, so that would be the reason for that. Im not going to get into an argument over how i installed it because itis the correct way...i think after 7 years of building these cars i think i would have aquired the knowledge to correctly install a hg.

If that was the case, you'd be able to tell the difference between a cylinder head that had been resurfaced, and one that hadn't.

 

[overdoseheroin]

If that was the case, you'd be able to tell the difference between a cylinder head that had been resurfaced, and one that hadn't.

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.