Jump to content

switch to mls gasket from IE?


Recommended Posts

Any advantage to swap to a mls gasket from IE on our race motor?  Besides tweaking quench using slightly thinner gaskets do they really hold up vs factory or leak oil etc?

 

Motor has S14 short block 13.24:1; block decked to use a stock S14 headgasket. We'll have the head off this winter to change rockers and use a bigger camshaft. Original intention of the build was make it around the stock S14 due to older issues with mls off the internet. It's been leak free for 4 years. Just want to see if anything has changed with latest mls gaskets. Stock s14 holds up and current quench is .035"  (pistons above deck .028") Compressed gasket height is .063" so would order a .060" gasket or another stock s14.  Thoughts?

 

 

 

 

Link to comment
Share on other sites

The only thing you need to be careful of with a MLS gasket is the surface finish on the block and head.  The surface needs to be glass smooth as the gasket will not “fill in” small machining marks or scratches.  I have been using Cometic MLS gaskets for years on M10 & M30 engines with great success.  
 

I found a problem running the stock S14 head gaskets with a M10 cylinder head.  The water flow through the head is different with the S14 head and the passageways through the gasket are different. I found that the water was not being run down the exhaust side of the head as effectively and under full load was overheating.  You can buy the M10 version of the MLS gasket with the correct bore for your S14 block and this cured our problems.  Lay a S14 gasket on top of a M10 gasket and ignore the bore difference but look at the difference in the water passages.  
 

If you are running ARP head studs don’t use the 90ft/lb torque spec that comes from ARP!  You will crush the head around the rocker shafts and actually loose clamping force between the cylinders. Remember you have less than 7mm between bores so the gasket isn’t as strong and wants to move, the MLS gaskets are much stronger here and the major reason I use them.  

  • Like 2
Link to comment
Share on other sites

Yes the finish on surface is a factor. Ours is close to mirror cut not sure what RA it is but very nice from the shop that did it. 

 

You sure on the gaskets coolant passage match up?

I just pulled these off the shelf to see exactly. The m10 one was on the motor we ran before using a stock gasket. The other is a stock s14 1.82mm used for mocking up the head several times to clearance and clay top pistons or ensure valve clearances. 

 

check it out; heres the M10 I highlighted in red paint pen can also see contact of old copper sealer spray 

AM-JKLUX33uhScrbVxncnH2jViMRLq5j882s49Tl

 

heres the same one where I hit it with some red spray paint to see better contrast when laying the s14 gasket on top (M10 bottom; s14 top)

AM-JKLXD0aot9QjTFodTDCMZ7d59YvjeHBaNKNEo

 

and here the s14 is overlayed on the m10 gasket; looks like more coolant flow using the s14

AM-JKLV6dSKesY8mPtuAyupL6OtITRIk1HdZEo-g

 

Sure the center triangle holes don't match using a m10 head but thats only for the s14 design etc. 

 

 

Link to comment
Share on other sites

Look at the 2 large openings on the exhaust side of the #4 cylinder on the M10 gasket.  the majority of the water comes into the head there and passes all the way to the front intake side where it comes out. 

 

The primary water flow on the S14 is from the larger holes on the intake side and flows across the head and exits into an external manifold that runs down the exhaust side of the engine (the water comes out between the exhaust ports.

 

Using the S14 gasket design the water comes into the head on the intake side and the easiest flow is straight up the intake side to the outlet at the front of the head.  We were not seeing really high temperatures measured in the water outlet housing but we kept blowing water out of the radiator because of over pressure.  The stagnant water around the exhaust ports was boiling and blowing water out of a 20psi radiator cap. 

 

The smaller holes in the gasket are to make sure there isn't any air trapped under the gasket, they are basically steam holes and not a major part of the water flow path.      

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

9 hours ago, Preyupy said:

Look at the 2 large openings on the exhaust side of the #4 cylinder on the M10 gasket.  the majority of the water comes into the head there and passes all the way to the front intake side where it comes out. 

 

The primary water flow on the S14 is from the larger holes on the intake side and flows across the head and exits into an external manifold that runs down the exhaust side of the engine (the water comes out between the exhaust ports.

 

Using the S14 gasket design the water comes into the head on the intake side and the easiest flow is straight up the intake side to the outlet at the front of the head.  We were not seeing really high temperatures measured in the water outlet housing but we kept blowing water out of the radiator because of over pressure.  The stagnant water around the exhaust ports was boiling and blowing water out of a 20psi radiator cap. 

 

The smaller holes in the gasket are to make sure there isn't any air trapped under the gasket, they are basically steam holes and not a major part of the water flow path.      

 

Ok now I see what you mean. S14 is a crossflow head so that makes perfect sense. Also after laying gaskets on top of each other with the larger holes on intake side you'd think more flow vs the other side smaller holes. Like a gasket being a thermostat. Yeah path of least resistance. Hmmm.

 

Wow ok we are blowing water out of a 18psi cap at times on track evident by the coolant catch can. A new cap has slowed the amount but it still happens even after making sure the modded 350 chevy radiator (Ron Davis) is at the right level after a few sessions. Some still does pressurize by and it's not a failing hg. I figured it was crappy caps. A new one does minimize it but still happens. Thermostat is a 75c with two 1/8 holes in the disc for bleeding.

 

Thanks for the insight on this.  Will look more into adding a mls when order the rest of our stuff from IE.

 

Edited by E21partscar
Link to comment
Share on other sites

22 hours ago, Preyupy said:

  

 

Ok two more direct questions.

Do you guys install the mls dry?. I've heard separate the layers of the mls, spray with loctite 99ma and rivet back together. This used to be a fix to sealing issues between layers that all coolant and oil weeping using mls. I've actually always been spraying my stock head gaskets with 99ma both sides liberally, let air for over 10min (evap the aerosol) then bolt down to spec. Never had leaks ever. Some like copper spray, but I like 99ma. It's like sticky high temp red glue. 

 

The mls sites list thickness in compressed heights? Just to be sure cause I figure steel doesn't compress so thats why they do this. If need a compressed gasket height of .060" then order a .060"?

 

We just built a differential to test (changed ramps). Went to our local autocross to try it out. Diff was a huge success. Large course, hot day. 16 runs later motor filled the radiator overflow again :)  When doing a autocross run and sit in line idling with fan on I think it's over pressurizing easier than a cool down lap on the race track. 

 

MLS definitely on the list.

Link to comment
Share on other sites

I have installed them dry and with “copper coat” I have never separated them and have never had a problem with sealing.  The specified thickness is the compressed thickness.  I even had them make a special M30 gasket fo a block and head combination on a old race engine that was over 0.120” thick.  They are great to work with. 

Link to comment
Share on other sites

3 hours ago, Preyupy said:

I have installed them dry and with “copper coat” I have never separated them and have never had a problem with sealing.  The specified thickness is the compressed thickness.  I even had them make a special M30 gasket fo a block and head combination on a old race engine that was over 0.120” thick.  They are great to work with. 

 

Thanks for all the replies, much appreciated. Now if IE will only get more chromoly dual spring retainers back in stock. 

 

Link to comment
Share on other sites

On 9/18/2021 at 1:39 AM, E21partscar said:

Wow ok we are blowing water out of a 18psi cap at times on track evident by the coolant catch can. A new cap has slowed the amount but it still happens even after making sure the modded 350 chevy radiator (Ron Davis) is at the right level after a few sessions. Some still does pressurize by and it's not a failing hg. I figured it was crappy caps. A new one does minimize it but still happens.

If this is for an S14 and coolant tank, your coolant cap is one of the problems.

 

I ran into this on my M3 for many years until I measured the coolant volume and coefficient of expansion, and inspected OE cap after cap wondering why there was coolant loss.

 

First, the coolant tank must not be filled to the arrow, it must be no more than the parting line. This is due to the expansion of the coolant causing the fluid to expand enough to reach the top. Fill ONLY to the parting line and no more.

 

Second, the OE caps have changed such that there is no secondary seal keeping the fluid from boiling over past the overflow tube. Get a Stant non relievable 22 psi cap.

 

All else being fine, that should solve your problem.

 

HTH a bit.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...