i own 2001 ext cab 4x4 has been a good truck. no major problem in 7 years. only complant is engine not very powerful. i dont expect it to be real powerhouse considering the size of truck and size of engine. last year added k&n cold air intake and throttle spacer helped throttle response & low end power, but didnt help in middle range. my question is how can i improve mid range power thanks srt

 

weak 4.8