Cometic Head Gaskets

[Chatt69chgr]

I read a magazine tonight (don't recall which one) that said that Aluminum heads were the way to go now since Cometic had solved the "problem" with the head gaskets. 

I am putting 440 Source Stealth 84cc heads on my 440.  It's bored 30 over.  I need a 40 -45 thousandths head gasket to achieve the correct quench distance.  My short block is set up for zero deck on the pistons.  Should I be using a Cometic head gasket.  I bought the ROL gasket from 440 Source when I got the heads.  That was a year ago.  I've got a sneaking suspicion that they are not 40 thousands.  I havn't measured them.  If I need a different head gasket, I'd like to get it ordered right away since my engine is going together as we speak.  I'd appreciate any and all recommendations, vis-a-vis, head gaskets for this application.

[Challenger340]

Cometic can be ordered in a variety of thicknesses to fit your application.

Cometic also Rec's a 40 ra, or finer, finish for "best seal" on the mating surfaces, I dunno what Stealth Heads have, you may wish to check  ?

[frederick]

Hi Chatt69chgr,

I have also got the source heads and ROL gaskets.
I have not measured them eather, do you think they are thicker or thinner?

Frederick

[Chatt69chgr]

I thought they might be thinner.  But I could be wrong.  Mine are at the engine builders so I can't get at them to measure them.  I just figured with all the people using the aluminum heads that there would be a concensus on the best head gasket to use.  I may need to call Cometic tomorrow to discuss the issue with them.

[67_Dodge_Charger]

check out cometic's website for part numbers and applications.  I had a clearance problem with my build, .093 gasket was needed.  383 stroked out to 496 10.5+ compression.  Deck height was my down fall after getting the block decked, bored and honed. 

http://www.cometic.com/

I did some digging around and remembered that I used SCE copper head gaskets.  I can't find my catalog but I remember that I used a .093 thickness copper gasket.  The catalog had a good list of gaskets and discriptions that help me narrowing my choice to what I wanted to spend and still meet my engine specifications.

http://www.scegaskets.com/

http://www.scegaskets.com/Shop/Control/Product/fp/vpid/6631356/vpcsid/0/SFV/32777

[six-tee-nine]

Correct me if I'm wrong (anyone)....but I was always teached to use "Fresh" head gaskets and no old or dated ones.
I also see many manufacturers put expire dates on their head gaskets.

I always get a new gasket when I need one and never buy stese things 1 year ahead....
I actually never wondered why this would be but I always kept it as a rule on engine biulding.

It might be a little off topic but I would not use the gasket you have laying around for a year...

[67_Dodge_Charger]

The copper head gaskets from SCE can be reused eight times...

[Chatt69chgr]

I looked at the Cometic website and called them and talked to one of their tech folks.  They make the multi layer steel, MLS, head gasket.  And it's expensive.  $100 for each one.  Looks like Fel-Pro has a MLS one too.  I tried looking at the Federal Mogul website for info on the Fel-Pro line but it is NOT user friendly.  I've never been able to get much useful info from any Federal Mogul website.  Then I called 440Source and talked to them.  They said the MLS would be a very good choice for use with the Stealth head.  Also said it would be overkill unless you were running very high CR.  I think that if the Fel-Pro MLS was available for a BB mopar that it would cost probably 80% of what the Cometic does.  Looks like the Cometic for a 440 30 over is supposed to be standardly available in .040.  But Summit Racing shows a two week del time.  Cometic told me they can make any gasket you want in 2-3 days.  And they make to order.   No stock.  I forgot to ask if custom sizes were more $$.  I am going to be surprised if they are since they make to order.  My engine is machined for zero deck.  I have started to really worry about piston rock and whether .040 piston to head clearance would be too close (I'am using Diamond Forged Pistons and the clearance was set at 5.5 thou).  I ran the numbers on the Diamond piston Website and it looks like bumping the gasket thickness up from 40 thou to 45 or 50 thou. won't affect the CR materially.  And I will still get quench.  So I'am starting to think that I may get a .050 thickness gasket at 30 over made.  They told me they make the gaskets 30 thou oversize to account for core shift.
Does anyone know if Fel-Pro has a .051 gasket that would be good for my application.  I'am looking at a 10:1 CR.  Or is there anyone else that might have a good head gasket to use. 
I want to throw one more issue out.  If I have chamfer in a cyl (at the top) do I need to make sure that the head gasket does not overhang the chamfer.  Sorry for the rambling.  I was just trying to download everything thats going through my mind right now concerning picking a head gasket. 

[firefighter3931]

  I have started to really worry about piston rock and whether .040 piston to head clearance would be too close (I'am using Diamond Forged Pistons and the clearance was set at 5.5 thou). 

You guys are suffering from paralysis through analysis.  The .040 number is very safe with a small bore build with forged rods....absolutely no worries. 



Ron