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#1
04-07-2022, 02:37 PM
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Detonation
So I'm getting ready for my new motor. I pulled the 7040263 carb off and sent it in for calibration for the motor. I put the old frankenjet back on it and now I have some audible detonation. I didn't have any of that with the other carb. I don't hear anything in 1st and 2nd ever. But in 3rd and 4th at WOT and higher RPM I can hear it. Regular cruising sounds fine. Is that due to a lean condition at WOT, or something else? I'm gonna go set my timing back a couple degrees today and see if that helps. I guess it may not matter much because this motor is coming out very soon, but I don't want to do any damage to it in the meantime.
Thanks.
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70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Ray Klemm calibrated Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear https://youtube.com/shorts/gG15nb4FWeo?feature=share |
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#2
04-07-2022, 05:59 PM
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I believe it was Lee Iococca that said pinging is the sound of good fuel economy!
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"At no time did we exceed 175 mph.” Dan Gurney's truthful response to his and Brock Yate's winning of the first ever Cannonball Baker Sea-to-Shining Sea... Still have my 1st Firebird 7th Firebird 57 Starchief |
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#3
04-07-2022, 06:45 PM
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If your car is currently feeding the motor off of the stock fuel system and your next motor will be making 450 hp or more then you will need to make changes to feed it right
Mean while when your currently in 3rd and 4th gear the motor is under a much bigger load then 1st or 2nd and if a lean or combination lean and excess timing condition will show up, it will be then,
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I do stuff for reasons. |
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#4
04-08-2022, 06:31 PM
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Yes it’s lean, could be a vacuum leak or the way the carb is set up compared to the other one. If you haven’t changed the timing that’s pretty much all it could be and the worst thing for any engine is being lean
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Happiness is just a turbocharger away! 960 HP @ 11 psi, 9.70 at 146. Iron heads, iron stock 2 bolt block , stock crank, 9 years haven't even changed a spark plug! selling turbos and turbo related parts since 2005! |
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#5
04-09-2022, 12:34 PM
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How close together was the carb swap and the last time you filled the tank with gas?
Clay |
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