How much fudging can be done with a head gasket
+ Reply to Thread
Results 1 to 7 of 7

Thread:
How much fudging can be done with a head gasket

  1. #1
    MLC - Mid Life Crisis probablecause's Avatar
    Join Date
    Jun 2008
    Location
    North Orange County (Brea)
    Posts
    1,132

    Default How much fudging can be done with a head gasket

    Is there a general rule of thumb for fudging with a head gasket to decrease compression?

    Just my opinion, but maybe it's time for the government to take down the bird feeder!


    Quote Originally Posted by Rexone;
    Try to ignore the haters, they are everywhere, just as in life.
    Quote Originally Posted by Pronstar;
    Liberalism: Logic's retarded cousin.


  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    i'm back!! 1QuickCP's Avatar
    Join Date
    Jun 2009
    Location
    Montana
    Posts
    687

    Default

    not really, just like having the piston down in the bore more. Of course by- by quench area, and thats not good for power or detonation.

    But yeah if you slapped a .100 thick gasket in there it would drop it quite a bit.

  4. #3
    Senior Member GT Jets's Avatar
    Join Date
    Jun 2008
    Location
    Morgan Hill
    Posts
    2,234

    Default

    Jsut do the math...

    If you run .125 more in head gasket, the combustion chamber gets that much larger.

    The combustion chamber quench area comes into play right away.

    Have you considered palying with cam timing also?

    How much C/R are we talking about reducing? I have done one point with gaskets, that is about all I felt comfortable with....(went from 11.5:1 to 10.5:1). I used copper gaskets to achieve it.

    GT
    GT


    Quote Originally Posted by Quickjet View Post
    Put a 300 on the back of it, Flywheel it and a nosecone. $15,000 later you'll have a 65 mph pile of shit......

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member earlbrown's Avatar
    Join Date
    Dec 2007
    Location
    LaGrange GA
    Posts
    285

    Default

    Quote Originally Posted by probablecause View Post
    Is there a general rule of thumb for fudging with a head gasket to decrease compression?
    There is a general rule of thumb.... ....but it's wrong!


    The amount of static compression change will vary depending on what you're at right now (and the bore to stroke ratio).

    For example if you're got a 7.5:1 engine, a few thousands here or there won't change hardly anything. If you're got a 14:1 engine a few thou can make or break you.

    You have to know everything to be able to calculate ratios but here's a simple app that will show you what a gasket change will do.

    http://users.erols.com/srweiss/calccr.htm

  7. #5
    Resident Ford Nut Sleeper CP's Avatar
    Join Date
    Dec 2007
    Location
    San Diego County
    Posts
    10,072

    Default

    Quote Originally Posted by probablecause View Post
    Is there a general rule of thumb for fudging with a head gasket to decrease compression?

    If I recall with my engine with a 66cc chamber (4.6 x 4.25 )the difference from a .040 gasket vs a .050 gasket is .3 points from 12.3 down to 12.0 those are " ball-park" numbers.

    Hope it helps you.


    Sleeper CP

    "Dark Sarcasm"
    Going fast is only half the fun ... what you make go
    fast is the other half.
    " A Government big enough to give you everything you want is big enough to take away everything you have"

  8. #6
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    just go here http://www.kb-silvolite.com/calc.php?action=comp and keep changing the gasket thickness until you get where you what to be. Word of advice though, as you lower the compression this way, the detonation factor goes down due to lower compression, but goes up do to lack of quench. Its a two sided sword.



    100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3

  9. #7
    Senior Member wildstreak's Avatar
    Join Date
    Feb 2009
    Location
    East Texas
    Posts
    520

    Default

    Quote Originally Posted by probablecause View Post
    Is there a general rule of thumb for fudging with a head gasket to decrease compression?
    More info plz. Why do you want to lower compression? You can get away with much more in our world with an entire lake for a radiator.
    But yes you can lower compression with thicker gaskets, not the correct way but it can be done. If you need to cut much you will have to use copper gaskets and you can get them THICK. With more info you will get more accurate and relevent answers.

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in

Digg This Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95