Question brought up by "Better size header"

[Falcons Talon]

In reading the thread on "Better size header" the concensus was that for a mostly stock engine, 1 5/8 were too big.

My question is this. Will my car benifit for bbk 1 5/8 longtubes?
On my 92 gt, what I have right now is cats cut out, black magic electric fan, underdrive pulleys, and a k&n box filter.

During spring break, I have to install an explorer upper and lower intake, a 65mm throttle body and 67mm egr spacer, and the ceramic 1 5/8 bbk longtubes with matching h-pipe.

I am saving up for 96 explorer heads and dynomax ultra flo weld mufflers.

I am pretty sure that the car will wake up when I get the gt 40 heads, but will I lose anything with the headers and the things I am going to do during spring break?