It's been a while since I've posted and touched the tuning in my truck. 3.4l engine.

It's currently running the smaller 2.8l throttle body, I believe it's about 270 cfm, I think. I am using the 4.3 injectors, and with the help you fellas, Mark especially, I've got it running pretty good.

But I have a question about using the 4.3 throttle body, which I believe is about 400 cfm.

To start, I hardly ever run this engine up to 3500 rpm. I might have hit 4k stomping the gas to pass someone, but I don't think I even hit that.

In any case, I understand that I might lose a little on the bottom end with the bigger diameter throttle bores, but since I am running a 3.73 rear, I'm not sure that would make a difference.

In any case, I am having a hard time understanding why a larger throttle body would make a difference at the rpm's I drive at.

Will I see anything?

(Please note that I am not sure I even understand what I am trying to ask here.)