Head gaskets-cometic or felpro permatorque

Big Block A body Tech

  1. challenger57

    challenger57 cuda57

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    I am building a 400-470 stroker with 11:1 comp. Cometics are so expensive 100.00 each. Will Others like felpro permatorque work just as well, this is a street machine. Any other suggestions of gaskets appriciated. Using arp studs.
     
  2. jos51700

    jos51700 Hemi Orange you glad it isn't a political avatar?

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    MLS is the shiznittosally. Are the Cometics an MLS gasket? If so, they're worth every penny.
     
  3. IQ52

    IQ52 Well-Known Member

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    I have used the 8519 PT1 FelPro gaskets many times to 12:1 and 787 HP without a failure.
     
  4. dantegray

    dantegray Well-Known Member

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    Im thinking of using this gasket at 10.0-10.5 compression with alunuim heads, am I able to spray 150-200 NOS? Are there any other gaskets recommended for 4.375 bore (4.480 gasket) with .039-.040 range (will put my compression 10.3-10.5? My pistons are .02 below deck height and I'm trying to keep the quelch right for 74-75cc Indy heads. Or do I need to send the block back to the machine shop to have it decked? I have heard alot of issues with the FelPro 1009 gasket, is this true or should I use this one?
     
  5. moper

    moper FABO Gold Member FABO Gold Member

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    Challenger - what material are the heads? IMO - Cometics are great when you need a custom thickness or are really pushing the limits of cylinder sealing. In your case you're not. They require a special block and head finish - one that some shops can't do and others don't bother looking into so you hear a lot about them leaking. If you have not machined the decks with them in mind, you'll need to do it again. If the heads are aluminum I'd use the Fel Pro 1009s because they have the flatteed fire ring to avoid brinelling the heads. If they are iron like IQ said - the 8519s are fine. Clean the bolt holes and threads, use the ARP lube and torque spec and don;t forget the surfaces of the wasters, and torque in steps with either setup.
     
  6. moper

    moper FABO Gold Member FABO Gold Member

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    Dante - the 4.375 bore is fine using the std 4.41 bore gaskets commonly available. As above -with aluminum heads I'd run the Fel Pro 1009s. Those are .039 compressed. Asl o - same deal - clean the holes and threads, use the right lube on any mating surface when you torque them, and torque in steps. What have you heard about the 1009s?
     
  7. dantegray

    dantegray Well-Known Member

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    I have heard of fire ring issues hanging in the cylinder. I just found some "Edelbrock 7325 ( Steel core laminate, 4.450 in. Bore, .038 in. Compressed Thickness) on Summits web site. Will these work?
     
  8. Dcuda69

    Dcuda69 Well-Known Member

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    I use the 1009's at 10.2:1 in a 470" with Eddy heads. It's been together as a street cruiser for about 4k miles. No issues at all.
     
  9. moper

    moper FABO Gold Member FABO Gold Member

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    The only heads that I've heard those issues with were the first batch of Stealths... On those follow Source's recommendation and if it were me I'd visually check the gasket on each head to make sure because it was not every head that had the issue. I "thought" Source had addressed that on the later castings...
    There are gaskets for the larger bores too - but IMO that's a waste space that will affect quench affect and compression but if that's what you have to do - I'd run a larger bore gasket with the pre-flattened ring before I ran a std round wire ring gasket on an aluminum head. But - I know others that run them that way.
     
  10. bOb shingler

    bOb shingler Well-Known Member

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    use the felpro's
     
  11. IQ52

    IQ52 Well-Known Member

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    Moper is giving you correct information. There will be no issues with the Indy heads. I have used the 1009 gaskets to 14:1 compression and 928 HP with Victor heads.
     
  12. Oldmanmopar

    Oldmanmopar Going left turning right FABO Gold Member

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    I always had a water seep with Cometic's on SB's I found the Mr.Gasket tri-metal's work better in the steel. But for a street motor I would also consider the use of a Composite gaskets. They seem to seal the water and oil a bit better . But the MLS do seal the high compression motors better around the cylinder.

    You could also take the MLS apart and spray all layers with copper coat. This would be the ultimate Race / Street motor gasket choice for boost or NOS. Or you could have a fire ring put in the head and use copper.
     
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