This is kinda hard to explain but under normal acceleration when my truck reaches 2500 RPM, Sometimes my tach will jump maybe 100 - 200 RPM and sometimes you can hear the intake sucking more air. It's almost like you give the engine a very very small shot of nitros. It also seems to accelerate a little quicker above 2500 RPM. And it's always at exactly 2500 Rpm. I was just wondering what could be causing this.

4.6 L
1997 4X4
Majior tune up done 20,000 Miles ago with Ford parts

 

the answer is simple you have most of your torqe at that rpm