whats up guys i got a question. i just did an engine swap and i driven prob about 1000 miles but every time i go to gun it i can take first to redline and itll be fine but when i take 2nd to about 5 grand it back fires i dont kno if its the spark plugs, the timing, or something else. if anyone has any idea please lemme know. thanks guys

 

well you are on the right track, check the plugs, timing and wires. See if you find anything there...if not move on to next ideas.