Exhaust question: Weird smell, because not dumped?

[TIMSPEED]

ok, here's my scenario...I've tuned and tuned and TUNED the carb, and everything I've done said the carb is DEAD-ON Air/Fuel at WOT...but everytime I romp on it, I get a WEIRD smell..now here's my question...is the weird smell caused just because I have a REALLY high flowing exhaust? (Long Tube Headers, Mandrel Bent Section through the Transmission Xmember, 2½" Piping into Straight-Through Hooker Maximum Flow Mufflers) Here's a picture of my exhaust, in fact:
I think my problem is...my exhaust is exiting directly under my bed and when I romp on it, the fumes are coming up between the cab and the bed, and I'm smelling them. (I always have the back window open)
Would either dumping the exhaust or running it out the rear sides solve my problem you think?
P.S.- I'm not getting ANY black smoke when I go WOT...