Which Cometic MLS Head Gasket to use?

[Lucas03es]

So I have come to the conclusion that I am going to use a Cometic gasket, this thread isn't about what brand of gasket I want.

When looking at the Cometic site, there are gaskets for 85.5mm, 86mm, and 87mm bores as well as different thicknesses.

When I bought my car it came with a receipt from the previous owner who didn't know too much about the car and got an 85.5mm .051" thickness cometic right before he bent the valves, if that matters.

I don't know if the motor has been bored or anything along those lines, so is there a way to check the bore of the block accurately?

It is a 92 gvr4 with a 97 7 bolt and assuming the stock 6 bolt head.

 

[scotyu]

So the car is already sitting and not your daily since your talking about bent valves and all? Strip the head and measure the bore before you order to make sure what size you need. No need to guess if your taking it off anyway. And if it is your daily then I would try to find a different one so you can strip and order after measuring anyway, . Good luck bro!

Edit: here's a link to the tool they use to do so. It is recommended that you dont buy the tool unless your going to be doing this sort of thing alot, or if your pockets are deep and dont mind haha.

http://forums.13x.com/showthread.php?t=167485

 

[black_gst]

i would advise against using a cometic HG unless you are having the block and head both resurfaced. i used on my 6 bolt swap a few months ago and while the block surface was in great shape(per the machine shop who said the block wasnt in need of decking and should take a MLS HG) and the head was resurfaced the gasket still didnt seal right and it started pushing coolant. now i used a mitsu MLS HG with copper spray and that has been working great!

do some more research on comitic and you will see that several people have run into the same issue

 

[Lucas03es]

Hmm i didn't think to go to my old auto teacher and ask to borrow a micrometer haha.

The car def. isn't my daily driver, that would suck if it was though.

When I drained the oil, there was a bit of coolant in the oil, but I think it was because the head wasn't shaved when he installed the old gasket. I am going to have the head shaved and probably sand down the block as well.

for black_gst, did you use the copper spray with your cometic?

 

[black_gst]

no i didnt use copper spray on the cometic but i didnt think it would be needed because the block surface was is perfect shape a fresh 6bolt and the surface was checked out by my machine shop and the head surface was machined as well

you can posibly tell if the pistons are oversized once the head is off they may say 50 on top of them and that would make them +.020" because their metric sizes and .50=.020" i could be wrong on the "0" placment but you get the idea

 

[timsturbotalon]

the 85.5 is for a motor bored .020

 

[Lucas03es]

So the pistons have to have those markings or they will be the stock size, or is that just on most?

 

[KevinRR]

So the pistons have to have those markings or they will be the stock size, or is that just on most?

I recently took the piston off my 2g 7 bolt and it has STD stamp on top of the piston. Which I'm pretty sure mean standard bore.

 

[1gDSM4g63]

Just use the OEM Mitsubishi MLS head gasket, MD 349347. They are much better than others.

 

[Lucas03es]

The top of the piston says 63DTF1 on it, and I don't see anything else.

Where is a good place to purchase the OEM gasket at a not so dealership price?

 

[KevinRR]

The top of the piston says 63DTF1 on it, and I don't see anything else.

Where is a good place to purchase the OEM gasket at a not so dealership price?

Mitsubishi Metal / MLS Head Gasket (DSM) - Modern Automotive Performance

Great customer service and fast shipping

 

[Lucas03es]

Can anyone show me where to get an oem composite head gasket, or even just the part number? I may consider that also seeing as how the block will not be surfaced. Thanks

 

[KevinRR]

Here an oem one Mitsubishi OEM Organic Head Gasket (DSM) - Modern Automotive Performance

 

[Killa_dsm]

You can also check JNZ JNZ Tuning Online- OEM Mitsubishi Parts

Composite oem: MD183808
MLS: MD 349347

 

[Lucas03es]

Thanks for the input guys, so is there different sizes for the OEM gasket I would have to worry about, or is it just the one standard size?

 

[velocitysport31]

Just get the stock oem composite with some arp's you will be good to 20lbs of boost.

 

[DSMtsi23]

Go to extremepsi.com and get there cometic MLS gasket. 85mm is stock bore. Thats what u need. And use Permatex copper spray on both sides of the gasket.. Torque those arps properly. Start the car let it warm up to proper temp then shut it off. Let the car cool down then(Next day preferably) take valve cover off and retorque those ARP studs.

 

[velocitysport31]

If you dont deck your block and resurface your head do not use a mls head gasket your asking for a leak copper spray isnt going to fix your bock if its not perfect. Go the safe way and use a Sock OEM Composite with arp's.

 

[Lucas03es]

Yeah I already have ARPs and i'm not looking to go crazy with the boost right now anyways. If I were going to, I would just get a built motor in the future anyways with an MLS gasket.

 

[velocitysport31]

Good Choice ive tried it twice with different metal gaskets both leaked. went with the good ole oem composite no problems and ive but down over 350hp with my 50 trim with no issues

 

[Killa_dsm]

Yeah do not run a mls unless your having both your head and block decked. And also many people run the stock Composite head gasket and arp's with high boost. So that should work for you.

 

[Lucas03es]

Should I torque the composite/ARP combo down to the recommended 85 ft. lbs. (If I remember right) or what would you guys suggest?