The power of both cars are so around the same that who ever gets the small
jump wins, But you didn't even let the S4 get into 6th, I find my S4 starts
hauling ass faster in 6th, But for compared prices.. Your M3 isn't too fast
for about 15000$ put into a 23000 car.. S4 are at max 14000$ and he
probably has maybe 5000 into it.. and still off the line eats you, Even
after you start getting traction you dont even catch up..
THIS s4 has over 20k into it. we were never talking about your friend. and he may have tials that do not require a built motor. i also said tial 770's which do require a built motor.
My friend owns a built s4 with tials and the total build cost him 9gs, at a shop that's parts machine work and the labour. And an s4 I bought for 8500 bucks.. And have seen them for 4500 in the states if not cheaper.. So I'd say total price for the car and performance 20gs, that m3 at the lowest is 14gs and the hpf kit is 15gs so yeah.. The s4 wins.