why can i make more boost at 3/4 throttle than at full?

[505powerstroke]

i was just curious why i can make more boost at 3/4 throttle than at full throttle with either my kem 345 or my h&s hot tune?

[fordfan30]

I am going to take a guess and say that 3/4 throttle is not enough to down shift so its under more strain.

[Isakson]

i agree ^^^ but i'm sure someone with more expertise will let us kno

[STROKER64]

I've always thought that with some of these tuners that "full throttle" could be short of your pedal hitting the floor and that is why some think they're boosting more before "full throttle". Basically that full throttle is before the floor and anything more is wasted or not read by the computer. May sound stupid, just a thought...

[Vettester]

.... .....

[tonypagnano]

boost occurs under load, and at 3/4 throttle your rpms are going to be lower than at full throttle putting a larger load on the engine. Hope this makes sense

[MD05]

Not completely sure but I think it is because of the EGR programing....

[08stroker250]

Try full throttle at about 70 MPH. You should see more boost then.

3/4 throttle at a lower speed is going to keep the torque converter locked. With a locked torque converter, your going to see more boost. WOT at a lower speed is going to un-lock the torque converter and allow the motor to rev higher, which will give you less boost.