<div class='quotetop'>QUOTE(91_bowtie &#064; Dec 26 2006, 11&#58;20 AM) [snapback]77354[/snapback]</div>
What size are your tires? What rpm are you hitting the traps at?
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285/50/20 - 31.2" diameter. Trap about 4200 rpm now. With 4.56 about 5200 depending on wheel spin at the bottom end. More into the HP range in 3rd no doubt. On paper with the 4l60E gear ratio&#39;s and OD the 4.56 do look good. Still plenty of RPM to pull topend for a truck. Cruise 65 -70 mph in OD about 2500 rpm. Not to mention how much fun it would be to drive around town and have instant smoke on tap, probably anywhere through second gear.

Still its all about 1/4 mile improvements in a street trim. I have my doubts that I could hook 4.56&#39;s on street tires. I would probably loose E/T due to wheel spin.