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  1. #1
    spud's Avatar
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    The Scoop on Reverse Cooling

    So whats the scoop on reverse cooling? I only know enough to be dangerous. Does anyone have any pics or comments?


  2. #2
    Moderator RX951's Avatar
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    Well, reverse cooling decreases cylinder head temperature and allows for much higher compression ratio. Lower cylinder head temperature also prevents detonation by eliminating hot spots in the combustion chamber.

    In our conventional engine design, water enters from the bottom of the exhaust manifold goes to the cylinders and circulates through the cylidner's water jacket then to the head.

    * Basically, the water is first heated by the cylinder barrels, and then hot water is subsequently routed through the cylinder heads and then to th epipe

    To combat the tendency to deto, we add free flows and D-plates for heat. We are also limited to compression ratios and spark advance under traditional cooling. Being limited also limts us to the extra power output and efficiency.

    Reverse cooling is nothing new. GM has been doing this since 1992 in the LT1 engine.....old skool guys even done this back int he 50's and 60's.... http://www.cottonowens.com/Ray_Nichels.html

    I'd liek to see the diagram shared for the GPR .

    What's getting the supply first, the head ? or the pipe to the head ?
    Is it getting supplied from the top of the stinger? or the back of the head ?

    * I would also assume that higher compression, more timing and a tighter squish can be tolerated under reverse cooling....on pump gas

    .02

  3. #3
    Moderator RX951's Avatar
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    ...........

    Attached Files Attached Files

  4. #4
    Very nice explanation Billy.

  5. #5
    Chrisrokc's Avatar
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    So I could gain some MPH and Torque by just switching the water lines?!?!

  6. #6
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    I have been doing this. It works AMAZING.

  7. #7
    Quote Originally Posted by IrishGpr05 View Post
    I have been doing this. It works AMAZING.
    How did you do it? Do you run higher compresion or timing than most?

  8. #8
    Duke's Avatar
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    I think Jeffsntx tried it and didn't notice much of anything. He probably has pics and diagrams. We ran reverse on the race boats 7 something years ago mostly because the heads were billet and held more heat.

  9. #9
    IrishGpr05's Avatar
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    I run a set of billet rius heads. Thats the main reason i did it but i have also been running 160psi compression with 3* keyway on a single pipe. I don't think thats anything to drastic but i def. think the reverse cooling helps. I mean the heads are always jsut warm to the touch, when before with the stock cooling setup it was always a lot hotter. Def. a noticable difference.

    I' no expert but i think it helps. Just my .02!

    I can take some pics if you guys want.

    -Jon

  10. #10
    MPower's Avatar
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    Yes, that would be great.

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