well i had a stock throttle body with a jlt and it worked alright. it surged but not bad, now i got a 70mm throttle body and my idle went to hell and the surging got worse. i got my tps to .99 i did all the work and nothing , it idled like crap. finally i put my stock airbox back on and walla my idle got smooth. one of my friends sold me a c&l inlet tube and a moroso cai and the car is smooth as hell. so im done trying to make the JLT work. maybe in a blower application i can see it work fine since the inlet is so huge but in a bolt on 5.0 it just didnt want to work.