A 1998 GMC Sierra standard cab/short bed. 350 Vortec automatic w/ Flowmaster, hypertech power programmer and K&N on 3.73 gears.

About what would that run in the quarter mile and top speed on those gears? I have a friend who I think is pulling my leg and exaggerating a bit.

Also, tires are slightly larger than stock.

I'd guess about a 15.0 or so quarter, maybe slightly higher...

id guess 16.0 trap speed of 85-87 mph

I would guess the 16 second range. It wont be blazeing fast.

I was thinking 16 too. Any idea on top speed of the 4 speed automatic? Assuming the vehicle is not allowed to go in overdrive at full throttle. 130mph ish?