Those numbers don't look bad at all. You're making 70+ horsepower at the wheels over stock. I'm sure your truck's overall weight does play a pretty big part in the 1/8th miles you've been showing, you're about 900 pounds over what the Xrunner weighs. If you believe every 100 pounds equals a tenth in the quarter mile, then there's almost a second right there and I'm sure it's effecting your 1/8th times. I'd be interested in what your quarter time is, I think you only posted 1/8th mile times? I'd think in the longer race against time, you'd see a little better result.