Why Does My 5.0 Sound Like A Big Rig?

[90GTFIVO]

I feel dumb for asking this question and I'm probably exaggerating a bit, but I've owned two 1990 GTs and a 1993 GT. The 90s both sound different than the 93, both making what I consider a loud blower type sound. When you rev the RPMs and accelerate (especially in 1st and 2nd gear), it sounds like you're spooling up some type of blower or compressor, like you hear when semis take off in low gear.

Is there anything different between model years 90 and 93 that would cause this? The only thing I can think of is the AC... the 90s both still had the AC, but the 93 was AC delete.

UPDATE: Just read jrichker's EGR theory post and the word vacuum stuck out to me. The sound I was trying to describe definitely sounds like a vacuum more so than blower/compressor. Being that just about all things were deleted by the prev owner of my 93, I'm assuming he deleted the EGR as well.

Is this my answer?

 

[smkshw]

by the description of a big rig,i first thought fan clutch,but you would know if its that im sure

 

[Shakerhood]

by the description of a big rig,i first thought fan clutch,but you would know if its that im sure

I was thinking the same thing when I read the description, kind of a roaring sound from the fan.

 

[Noobz347]

Post an audio clip.