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I hear it sometimes on some of the big guys cars at sgmp and other places. When the car is on the 2 step and it stumbles and sounds like it drops the boost out the pipes then it's right back on the 2step. Anyone know why this happens?
 

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I hear it sometimes on some of the big guys cars at sgmp and other places. When the car is on the 2 step and it stumbles and sounds like it drops the boost out the pipes then it's right back on the 2step. Anyone know why this happens?
Shitty tune up ;)
 

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I've had this problem with my car. I never got around to tuning it out and I haven't raced in the last year but it is at the top of the list when I get the car back together. I would have guessed too rich and the fuel is burning beyond the turbo and backfiring slowing the turbine . I'll be checking this thread often if anyone has further tuning advice
 

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I've had this problem with my car. I never got around to tuning it out and I haven't raced in the last year but it is at the top of the list when I get the car back together. I would have guessed too rich and the fuel is burning beyond the turbo and backfiring slowing the turbine . I'll be checking this thread often if anyone has further tuning advice
Clutch cars take timing out and throw more fuel at it that's why you see big phucking Flames out the pipes :p
 

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Its a lean back fire on 2 step. Running lean builds boost faster in can be a fine line. I will set in the car with the lap top and 2 steping building a fuel map in that part of the fueling table.Methanol is not as bad as the C-16 was I learned a important lesson on gas always do 2 step testing with the intercooler full of ice like a normal run .On the computer the back fire shows up as pressure spikes. Sometimes if the pressure spike is enough it will cause the regulator to add more fuel and the DC to go up enough the 2nd set of injector kicks in then everything is unhappy lol
 

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I am so Surprised that no one has came up a way to get the shaft speed were they want without All that popping and banging I seen it done 30 years ago and know exactly how they did it . He could make 20psi in less then half a second it was crazy
 

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lol dont ask how but if you get your starting line timing set up at 30 After TDC you can open the throttle to 5000 rpm in neutral and make 20 lbs instantly
 

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Be ready for some of the loudest cannon firing you have ever heard/felt, LOL!! Years ago when Moran was the 1st car in the 5's he said no amount of shit crammed in your ears could stop you from hearing/feeling it and he nor the engine could stand it for more than about a half a second. It damn sure works though.
 

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Clutch cars take timing out and throw more fuel at it that's why you see big phucking Flames out the pipes :p


auto also as long as its already up on the converter before you do it .

My "crutch" carb worked pretty good for that .

7531 to pull the timing and open the power valves at the same time .

The Holley has a boost builder function that seems to work on my new set-up . Just have to get to the track more to test it . So far it seem to work as long as its up on the converter and just starting to build boost before activating the timing retard and fixed fuel .

Probably would be a different story if the converter was right ..........that fine line between street and strip .:mad:
 

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I haven't had the sneeze happen so far. The BS3 typically goes rich for a split second on the 2nd set of injectors coming on. I bring them on pretty early at no more than 25% TPS to avoid this being a problem later in the staging/pull/pass when it can be more of a problem. I also do preliminary fuel map coming up on converter to full stall without the 2-step so you can actually use the O2 data to tune by then you are sure to have enough fuel on the 2-step and can fine tune from there. Just my $0.02
 
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