Hello all, Im not sure if this is the right place to post this because Im not sure what the problem is exactly but the car is running a microsquirt and I just got it running. The setup is a stock explorer short block, e303 cam, ported gt40P heads, holley systemax intake, 75mm throttlebody, on3 turbo kit, 340lph fuel pump, 52lb injectors and Autolite 103 plugs gapped to .025. Timing was set at idle to 15* and confirmed in TunerStudio. As the title says the car will break up at about 3000 rpm under load and start backfiring out of the exhaust. Im at a loss because other than that the car appears to run good. It idles well in closed loop and cruises smooth. Fuel pressure stays within the 38-40 range, stays steady under load and increases under boost. AFR stays around 12.5-13 under load. I tried setting the timing to fixed at the base 15* to see if the advance was messing it up and that didnt make a difference. I even took the charge pipe off the throttle body to see if the problem was boost related and the car still has the same problem. In 3rd gear if I roll into it without the charge pipe the car has almost no power and I cant force it past the 3000 rpm even with the pedal to the floor and it breaking up. Ive attached my .msq file along with youtube links of videos of my fuel pressure, AFR, and boost gauge while the problem is happening. This is my first attempt at trying to tune anything like this so let me know if I left out any critical info. Thanks in advance!
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