Metal head gaskets that actually hold power

[Doug99RS]

Has anyone bothered to check the flatness of both the cylinder head and the block when installing the new MLS headgasket? Also, what kind of cleaning methods were used when removing the old gasket material from both the block and head?
I have little experience with the turbo cars and no head gasket experience with them. However, I am quite familiar with the Chrysler 2.0 SOHC, DOHC and 2.4L DOHC headgasket repair procedures as I am a tech at a chrysler dealership.
The only time I see any failures with the MLS headgasket is when people do shotty work cleaning of the old gasket, if they even bother to do the job properly. I've seen many people drain the coolant, take off the valve cover, take out the head bolts just far enough to raise the head, slide out the old gasket and slide in the new one. Cleaning NONE of the old gasket material off. Common problems include coolant leaks, oil leaks, and I've even seen one destroy the engine by starving the head for oil.
Intentional fraud asside... there's the improper cleaning methods and lack of inspection and mis-diagnosis that can add to more head gasket problems.

http://www.carolinadsm.com/cgi-bin/ikonboard.cgi?;act=ST;f=16;t=2

Above is the technical service bulliten regarding the proper methods for cleaning the gasket material off.

I ask because I'm curious, not trying to bash or point fingers. I just haven't seen the MLS gaskets fail and if they have been... I'd like more info on them and what other info supports the fact/opinion that the gasket was to blame.
Thanks,
Doug

 

[candela]

Hey Dsmperformer I think your time may be a little off dude... 12.3@126mph? That would give you the record for fastest 16g powered dsm (mph wise) with or without n2o.


Doug,

I think the situation is a little different thn what your talking about. Most of these guys are talking abou tgetting into these HG not because of preperation malfunction, but just because they cant handle the boost. Im not saying that cleaning the block and HG and having a PERFECT contact surface isn't needed, just saying that these are mostly for high boost situations. Ive only blown the stock HG in my car and don't really know how these guys must feel blowing a metal HG at the track... But I learned from this thread, so thakns everyone for their input.


Austin

 

[DSM Performer]

Check your numbers because i know lots of people running faster times then me. i Dont know what the DSM Scene is lik ein your area, but here, there are a lot of sick DSM's. I will scan a time slip if ya want, and I have a Video of one of my passes. SO if you want proof. I got plenty of it.

 

[rdrkt]

Originally posted by DSM Performer
I've hit low 12's (12.3 @126) and I havnt had a problem at all yet.

What exactly did you change? In your profile it says 12.4@106 How did you gain 20 MPH and only lose a tenth off your ET? Not calling you a liar YET but it looks really um fishy. Unless there is a TON of mods that you failed to mention in your proifle. This doesnt have anything to do with the fact that you are trying to sell your car here does it?

 

[OWGTI]

Those Cometic gaskets are really nice. I work at a harley speed shop in my spare time and thats all we use on the high performance engines. When i put a new engine in my DSM i used a FEL PRO gasket with ARP studs and have hit 17psi with no problems, but thats it. When i have a problem i will of course install a Cometic gasket.

 

[jayntguru]

I've been using the HKS gasket for two years now. Block and head prep is key, I had both resurfaced. Use the mitsu MLS gasket sealer too, it helps. Mine has been reused twice now, using ARP studs at 100 ft lbs or so. Been through many overheating, boil over episodes, 34 PSI boost spikes, 12 hour drive to the shootout each way in 2001, and about 100 drag strip passes in that time.

 

[tanner261]

I'd never recomend a Felpro gasket to any DSMer. I blew one on 18 psi with no knock. One thought was that I had too much timing in the midrange, but I blame it on the gasket being inadequate.

I then replaced the Felpro with a mitsu metal and the only mating surface prep I did was gasket remover and a stack of razor blades. I retorqued the ARPs to their recomended specs and that gasket held for over a year at up to 23 psi on a small 16G. I'm surprized I got away with the gasket sealing without having anything decked or using copper spray. I consider myself lucky.

For my new longblock Buschur recommended a factory mitsu composit gasket, and to never use a Felpro. They claim this is what they use on all their cars, plus it put me at a 9:1 compression ratio. I'm pretty sure they O-ring thier setups too, but that is for high boost (25 psi+) and nitrous. I torqued the ARPs to 80 ft. lbs. with their moly lube and I'm expecting it to hold whatever I throw at it, excluding nitrous. I also don't recommend over-torquing ARP studs <-anyone pay attention to how important it is to use a torque plate while boring cylinders? If your block was bored with a plate, and you torqued down your cylinder head tighter than the machine shop, you just negated the benefits of using the plate.

 

[awd4bangr]

Originally posted by tanner261
I also don't recommend over-torquing ARP studs <-anyone pay attention to how important it is to use a torque plate while boring cylinders? If your block was bored with a plate, and you torqued down your cylinder head tighter than the machine shop, you just negated the benefits of using the plate.

This is why you specify to the machinist what fastener to use and what torque value. If you don't odds are the stress plate will be fastened with bolts and stock torque values. When you add in studs and high torque values your nice two stage stress plate hone job was a waste.

 

[HoleShot]

RA is a way of mewasuring the surface texture, or who rough it is. in cases like the 420A, MoPar wants you to use this snot spray to seal the gasket and this is not needed if the RA prep is in order with what the gasket calls for. The mitsu casting of the heads is ok at best and the finish from a fresh mill is always better. A RA that is in the 20-45 range can take a MLS with NO spray at all. now this is with the head and block checking in at a very smooth RA. Many people do not do the prep work like was said above and this is not talking about the " slip and slide gaskes" that were named above by doug. But the mods like recever groves and such is subject to machinest work. I'm not saying that it was wrong but it sure wasn't sealing.

Many people do not even know what this is and how to go wbout finding out what the RA that the gasket calls for. This is not easy to find but it out there. I am not a fan of sealent on the gasket and copper if anything is the only thing I use. the idea that this snot would help seal and not burn in a race app is silly.

In all the Mitsu MLS was NOT made for performance reasons. It was made to correct a over milled head. ( a deck should never be decked unless it is a MUST and a new block is not a option ) by broing the head up it will help correct cam timming problems and clearance as said above but why is it expected that it was made to peform better?

Most MLS gaskets that are performance made are 3 layer not 4. some 4. A lot have to do with what the app calls for. I have a GREAT atrical from a machinest mag that is only talking about MLS and prep surfaces, what is the false statements and what is true. How OVERTORQUE of a sutd does more HARM then good and how it is not needed. How RA surface will effect the seal and the need for O rining Vs the given app.

cometic and HKS have filled the need for the head gaskeyts for a while now and we have worked with all of them. From stk to mitsu metal, HK$ and one off copper as well as Cometic. They all have a need. A reason for each app that they go in to. If your going 12.s I don't see the need for a MLS unless your in the head already. We have build many 25PSI stk gasket cars. with studs and proper install it was never a probelm. They never got over amped with timming and thus have lasted.

so not much of a point but just some info and personal experance.

 

[T6Rocket]

The whole reason for o-ringing the head is to use a composite gasket for it to sink into. IF you use it with a metal gasket, you aint got much surface area touching!

Al