well my set up already up in the 440whp range ....so when u running all that this stuff audio and modds hids etc. and you keep killing batteries cause they're taking a beating ....and all of them where duralast .....u notice the big difference ...as for motor pull harder im not talking no wopping 100 horsepower ....its just cleaner gain a lil rpm between 6 and 7 no tune cause i lost it switching up batteries .....