Problem resolved ( so far...lol).
Okay... so it wasn't the fuel pump issue (i didn't think so because it only happens when using launch control). Wasn't any spark plug issues or ECU problems... I consulted Burger on the issue, and Terry said that it definitely sounds like 'throttle closure' do to traction control which can never be turned off 100%. He suggested to reduce the boost via 5 psi in the 1st gear settings under the custom menu. This worked! Then I tried reducing only 3 psi (still get 2 psi in 1st gear) and it worked as well! I left 2nd and 3rd alone. So issue resolved thanks to Terry!
By the way... 80kph - 120kph passing gear time was 3.08 sec ... the GT1 is 3.0 ... so you get the power of a V6 stinger in some areas of the power curve with the JB4 on Map 3