Blown BBC copper Head gasket

Discussion in 'PSI Superchargers Tech Questions' started by Milan, Sep 19, 2009.

  1. Milan

    Milan New Member

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    Hi guys, I have a stock gm 454 block with ARP studs in an 8-71 E85 Camaro. The blower is currently underdriven as I am trying to work the bugs out of my combo. I torqued the studs to spec and I used SCE 090 copper head gaskets. the compression ratio is a calculated 11.98:1. After doing my burnout I started pushing water out of the radiator. Should I torque the studs even tighter or do I need to drop the CR? you suggestions are much apreciated please keep in mind that this is a self funded (limited$$) car.

    Milan
     
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  2. Moparious Maximus

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    What are you torquing your studs to?

    How much boost are you making?

    Is this an O-ring/flat copper setup or are you using the ICS gasket?
     
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  3. Milan

    Milan New Member

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    The studs are 135-4001 and torqued to the ARP spec with 30wt. I tried but I cant find the instructions that had the spec on them. I want to say 75-85 pound Ft. The gaskets areflat copper and I sprayed them with coppercoat. The boost is only 5-6 lbs
     
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  4. tafccrewguy

    tafccrewguy New Member

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    Thats alot of compression ,especially for e85,which is never consistently sold at 85% from what ive heard.Do you have any full throttle runs or trips down the street at wide open?Whats your timing at?You might have detonated it and cracked something(block)or pushed a gasket.
     
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  5. tafccrewguy

    tafccrewguy New Member

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    Also if you fill the rad all the way up it will push some water out.On my car I use a 35 lb cap cause it trys to do the same thing.
     
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  6. Milan

    Milan New Member

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    No full throttle passes yet 32* timing. No hints of detonation on plugs or audible. I was wondering if I should crank the Heads down to 100ft/lbs
     
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  7. Moparious Maximus

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    Your compression does seem a bit high, but in my opinion it should work fine with that low of boost.

    If those studs are 7/16" 100ft/lbs might be too much for the stud, if the are 1/2" heck yea bring that torque on.

    Is this thing O-ringed?
     
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  8. Money Shot

    Money Shot Member

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    I torque my BBC with 7/16 studs to 100 ft. lbs. Its pretty scary but if you do it in 3 stages it works out OK. If your block is not O-Ringed it needs to be if you want to continue to use copper head gaskets. Your compression ratio with just 5lbs of boost comes out to close to 17.1. Have you tried the MLS gaskets? They work pretty good for non O-Ringed combos such as yours. Also, What cam are you running? What is your cranking compression?
     
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  9. Ron C

    Ron C Jr. Dragster

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    "Hi guys, I have a stock gm 454 block"

    Stock blocks will not take much over torquing before the deck starts distorting and leakage will go from bad to worse. Be careful about that.

    Blessings...........Ron
     
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  10. Moparious Crewcheif

    Moparious Crewcheif New Member

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    So true. Take a good flat stone and stone the deck you will see that the deck has pulled up around studs. Water blocks are good for this. We have used the SCE copper that has a wire imbedded around the bore. Acts like a O ringed block but kind of cashy.
     
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  11. dragcars

    dragcars New Member

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    You will also start pulling threads on a stock block @ 100 ft/lbs. My limit now is 85 with o-rings
    frank
     
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  12. Milan

    Milan New Member

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    What would be the CR limit so as to avoid the cost of o-ringing. How much should it cost to oring this block /heads.

    Thanks for all the feedback
    Milan
     
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  13. Moparious Maximus

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    If its not O-ringed you cant run a flat copper gasket at all, there are several gaskets that work without O-rings, and should do fine for what you are doing....... well that depends on how much boost you want to make in the future.

    I run a 572" big wedge chrysler at 11.5 to 1 static comp and 16 psi boost on alcohol, around 1500 hp and its not O-ringed. I use SCE gaskets ICS or Intagrated Combustion Seal. Its a copper gasket with O-ring material around the combustion seal area.

    I use 7/16 studs torqued to 85lbs with ARP lube, and they seal fine.

    There is also Cometic Gaskets, they make a MLS gasket that ive heard good things about, but Ive never ran them, we tried but they leaked water.

    About your CR, I dont know enough about E-85 to even have an opinion, if I had to guess, my starting point would be 10.5 or 11.0, but again that is a guess.
     
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    Last edited: Sep 22, 2009
  14. pat Iley

    pat Iley Member

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    compression seems to be a little on the high side .two questions did you retorque the heads after you put them on and fired the moter and it reached normal operating temp. and what did you use for thread sealant on the head studs.
     
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  15. Milan

    Milan New Member

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    I used black RTV sealant on the studs. I ran the motor for several minutes but I dont believe I thororoughly warmed it up. Should I try retorquing the studs before I DISMANTLE IT OR IS THIS A CASE OF ONCE IT LEAKS ITS OVER? (sorry on the caps)
     
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  16. pat Iley

    pat Iley Member

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    I have a small block cast iron block. the problem i encountered was the water was coming up the studs. i tried different thread sealants with no luck, then i was told by a arp rep at the track to use Right stuff and it should cure my problem.It is more expensive than other brands but many racers swear by it.Once installed you can use a rad pressure tester and pressurize your cooling system and check to see if it holds pressure. if not remove valve covers and see if it is coming up the studs. My block is not o-ringed neither and i am using fel pro head gaskets with the rings made for supercharged applications with no problems. motor is
    383 cubic inch
    8-71 weiand supercharger
    10% overdriven
    Enderle bugcatcher on alcohol
    motor has run 7.59 at 173mph making 24lbs boost. I believe that using copper gaskets that are flat without the built in rings to seal your combustion chamber you are going to have problems. they are also more expensive and if your block was o-ringed these gaskets can be reused as long as they don't get damaged by a lean out condition, which usually damages the heads also. When you use a copper gasket you must install then start the motor and run it without a load until it reaches normal operating temp then re-torque the heads as the copper will require this for proper sealing. this is a one time proceedure when the gaskets are new and are hardened at the factory. The cost of having your block machined for o-rings can be expensive and must be done by somebody that knows how to do it proper or else you wasted your money and might wreck your block. the o-ring process is superior to the other gaskets but unless you are making big boost it is not required.
     
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  17. Milan

    Milan New Member

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    Pat what is the Felpro gasket model. Thanks for the help!
     
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  18. pat Iley

    pat Iley Member

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    I would suggest that you get a hold of the company direct to insure you get proper gaskets for your combo. some heads require different gaskets.there are many companies out there like Fel pro or another company is SCE. both companies sell good quality gaskets that cost less than copper. however if you want to try copper SCE makes a brand called titan self sealing. i do not know if they can be reused but for the amount of boost you make' cost wise i would use regular gaskets.
     
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  19. pat Iley

    pat Iley Member

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    the gaskets that you wanted to know about are regular performance composite gaskets. the important part is if you have aluminum heads they make gaskets with a pre flattened copper fire ring to minimize brinelling of your heads. the fel pro part # is 1010 are the ones i use on my sm bl chevy.
     
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