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getting psyched for Engine Masters 2011 - inspirational video inside :-)

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  • #16
    Originally posted by CDMBill View Post
    Spidey, if you mean the current one, it sure seems to be, BES walked all over everybody else last year with their 3rd gen. Quite the Frankenstein intake and ignition setup. That said if the Hot Heads 1st gen Hemi hadn't had the last minute issues they had the field covered with that number Scott mentioned.
    I am far more worried about having Tech Difficulties than I am our EMC score. Danny proved that we can score better than the winning numbers... the problem is, Tech Difficulty - and also Difficulty with the Tech guy.

    One of the rules last year was that we only had 2 20-amp fused circuits available. So you had to make your engine run on a max of 40 amps of current, which is a real challenge with 8 coils, 8 injectors, a water pump, etc. We spent a good 3-4 hours working to get our power consumption below 40 amps.

    When I got to the competition in Ohio and saw what Bischoff was running for ignition - an easy 60-70 amp load - I figured they'd never make a pull. Sure enough, when they went to start the engine, they popped both fuses as soon as it fired. The tech allowed them to quickly bypass the fused power and run jumper cables to the battery. I think EMC even provided the jumper cables. No "setup time" was taken away from them either.

    Result is a new Hot Heads team rule: "don't let the tuner speak with the tech director"
    www.realtuners.com - catch the RealTuners Radio Podcast on Youtube, Facebook, iTunes, and anywhere else podcasts are distributed!

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    • #17
      Originally posted by dieselgeek View Post
      Result is a new Hot Heads team rule: "don't let the tuner speak with the tech director"
      Good rule!!
      I'm still learning

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      • #18
        yep , the new german flavored hemi
        the next gen GM V8 is on the horizon , lets see if politics ruined GM powertrain

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        • #19
          Originally posted by dieselgeek View Post
          Here's an interesting question - how much compression is too much? Ray Barton told us a "certain recommended number" on the Early Hemi, he says more than this number will result in diminishing specific output (lower power-per-cubic inch).
          I suspect this means that practical concerns like charge and flame obstruction due to large domes outweighs the diminishing returns from thermo. Combustion thermo works on pressure ratios, not compression ratios. Adding 2 points of compression to a 10:1 motor is a 20% pressure ratio increase. Adding 2 points to a 15:1 motor is only a 13% pressure ratio increase.
          Last edited by Aircooled; July 19, 2011, 10:14 PM.

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          • #20
            Originally posted by TC View Post
            The dome isn't as tall as you think......with that cubic inches you can get 13:1 with a flat top piston, you just have to have the right head gasket and chamber CC's and zero deck the block.....

            Ooopps forgot it was a Hemi........, damn I always think chevy........ ya it'll have a big dome......

            Damn TC, good thing you caught yourself on that one!
            It can sometims be a little difficult to get really high compression ratios out of a hemi. DG, how are you going to raise it, with different pistons and/or rods? or do you just have really thick gaskets on it now? Over the last year we have devoloped a IHRA, 94%+ ratio, thats around 13:1, and a NHRA, 94% ratio thats closer to the 14:1 area. Not that I really have any secrets but we get it close with a piston and rod swap and depending on the weather select a head gasket. In this kind of heat we are right on the edge and leaving marks on the exhaust side of the pistons. That's with a 99cc chamber head. I've found that on a hemi it's pretty important to pay attention to the burn pattern on the tops of the pistons and you can kinda zero in on your compression. If your really close you'll see it on the even side first (2,4,6, and 8 side) and the egts will start to take a dive, plugs start looking rich. (it might show up eariler on your engine because of a single spark plug though)
            Now days I'm more intrested in cranking compression numbers, I usually just test 1 and 6. After you're done with all of this I'd be pretty intrested in some more detailed specs if you're willing to share. Of coarse I hear you could always move your wrist pin toward the intake valley for a little extra oomph to get you over the edge!
            Last edited by A/Fuel; July 20, 2011, 06:35 AM.
            Originally posted by TC
            also boost will make the cam act smaller

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            • #21
              why the true chrysler hemi hasn't dominated pro stock since 1971 ..the pistons are too heavy

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              • #22
                Speaking of pistons, here is an example of a 2 year old style combo from a .500 short deck, 4.375 bore 3.6 stroke, 6.88 rod. I tried to get a pic showing the correct burn pattern.
                Attached Files
                Originally posted by TC
                also boost will make the cam act smaller

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                • #23
                  Here is another, note the exhaust valve mark.
                  A lot of people still use this style too.
                  Attached Files
                  Originally posted by TC
                  also boost will make the cam act smaller

                  Comment


                  • #24
                    A/Fuel, our compression increase will come from simply piston height, as I understand it.

                    I have never tuned by looking at burn patterns, presumably it's a lot easier when you are pushing your kind of cylinder pressure?

                    All this is over my head - I'm focused on getting the right mixture and correct timing for peak power via the electronic controls... maybe Bob will chime in with better feedback! lol
                    www.realtuners.com - catch the RealTuners Radio Podcast on Youtube, Facebook, iTunes, and anywhere else podcasts are distributed!

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                    • #25
                      Originally posted by SpiderGearsMan View Post
                      why the true chrysler hemi hasn't dominated pro stock since 1971 ..the pistons are too heavy
                      I don't know what the bob weight is/was on a old pro-stock hemi but ours is around 3400.
                      Originally posted by TC
                      also boost will make the cam act smaller

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                      • #26
                        Originally posted by A/Fuel View Post
                        I don't know what the bob weight is/was on a old pro-stock hemi but ours is around 3400.
                        I was going to say god damn that's a lot, but then I looked at the pics and understand why........Those are some beefy ass rods and pistons........

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                        • #27
                          The wrist pins are like a roll of quarters, but weigh more, lol.
                          Originally posted by TC
                          also boost will make the cam act smaller

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