old motorhead
10-07-2006, 07:48 AM
Just got my truck back from his shop and all I can say is WOW! He did the tuning, Radix, cam, shift kit, and boost cooler install for me. We discussed what I wanted and didn't want as far as driveability, performance, and reliability were concerned. I told him I wanted the feel of a built big block under the hood without the noise, driveability issues, and poor fuel economy. The combo of parts in my singature is what he suggested and what I agreed to.
The GMC is an absolute blast to drive. It's over 400ft/lbs of torque anywhere above 2400 rpm. Torque peaked around 450 at 3600. Hp peaked at 415 at 5250 rpm. Allen said those numbers converted to engine torque and Hp would be over 500 hp and 550 ft/lbs. The truck has no bad manners other than a tendency to roast the rear tires with anything over moderate pressure from my right foot. Haven't got a chance to check the fuel eco yet, but I'm expecting it to be close to what it was pre radix. No need for a looser converter as this thing has awesome low end power. I will eventually either opt for a 6speed or a built 65. I'm hopeing the one in there now will last a while though.
About the only thing I'm going to add is a quieter exhaust. The corsa wasn't too bad pre radix, but it's much too loud now. At WOT, I don't think open headers would be much louder. Allen had my truck on the dyno when I got there to pick it up. Without fingers or plugs in one's ears, I'm sure permanent hearing loss would have occurred.
Allen Nelson is one sharp guy. He's a tremendous resource when it comes to tuning and understanding what makes these things run. We talked about all sorts of combinations including STS turbo systems. After all that, we settled on the setup below. Attaboy Allen! You got this one dead nuts right on.
The GMC is an absolute blast to drive. It's over 400ft/lbs of torque anywhere above 2400 rpm. Torque peaked around 450 at 3600. Hp peaked at 415 at 5250 rpm. Allen said those numbers converted to engine torque and Hp would be over 500 hp and 550 ft/lbs. The truck has no bad manners other than a tendency to roast the rear tires with anything over moderate pressure from my right foot. Haven't got a chance to check the fuel eco yet, but I'm expecting it to be close to what it was pre radix. No need for a looser converter as this thing has awesome low end power. I will eventually either opt for a 6speed or a built 65. I'm hopeing the one in there now will last a while though.
About the only thing I'm going to add is a quieter exhaust. The corsa wasn't too bad pre radix, but it's much too loud now. At WOT, I don't think open headers would be much louder. Allen had my truck on the dyno when I got there to pick it up. Without fingers or plugs in one's ears, I'm sure permanent hearing loss would have occurred.
Allen Nelson is one sharp guy. He's a tremendous resource when it comes to tuning and understanding what makes these things run. We talked about all sorts of combinations including STS turbo systems. After all that, we settled on the setup below. Attaboy Allen! You got this one dead nuts right on.