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I know there is a similar thread but this one will include what I feel is the rest of the puzzle to correct GM's minor short falls in the early trucks. I feel they are the best trucks GM has ever made esp. since the 07.5-13 trucks are so poorly built. Anyhow, I am in the process of getting a fresh motor for the truck and plan to do all of the upgrades that need to be done to the truck. I made a run down to see Pat and Kurt for a baseline pull on the dyno. The truck made 247 HP and I believe 267 TQ. That is stock other than a Banks cold air. I haven't even tuned the truck. I will post the graph along with the data log when I have the sheets. The plan was a fresh 5.3 but I found some rust in one of the cylinders so we will have to put up with a 5.7L. It will be flat top and 243 heads so no more poor CR. It will also be getting a NNBS intake with throttle body, a drop in CamMotion truck cam (206/210 deg. @ .050- .553"/.553" 115LSA), and electric fans. After a Pat G tune it should make much more power and hopefully not loose, possibly gain, some fuel mileage.(when I keep my foot out of it). I have been doing various mileage checks and getting around 13 city and 15 highway Stay tuned and will update thread as I get more info.
It's been way too long but finally got this truck back on the dyno. It was an unfortunate fate for the 5.7. Number 8 rod spun a bearing so back in with the OLE 5.3 short block. This means we are down in compression even more so than a stock 5.3. That being said, this dude still made 309 HP. I will post the actual graph soon but that's a 63 HP gain from stock. It pulls like an absolute bull with 6k pounds in tow. Once again, it was a great experience with Pat G on the Mustang MD250 dyno. We tuned a heads/cam GTO just before that made 430.
It's been way too long but finally got this truck back on the dyno. It was an unfortunate fate for the 5.7. Number 8 rod spun a bearing so back in with the OLE 5.3 short block. This means we are down in compression even more so than a stock 5.3. That being said, this dude still made 309 HP. I will post the actual graph soon but that's a 63 HP gain from stock. It pulls like an absolute bull with 6k pounds in tow. Once again, it was a great experience with Pat G on the Mustang MD250 dyno. We tuned a heads/cam GTO just before that made 430.
Thats a great gain! Should really pull decent. I haul my vette with a little 4.8 through the mountains from virginia to Indiana. That a 5.7 GTO?
01-11-2018, 09:40 PM
04' Z71 The right way w/ drop in truck cam 
It will be flat top and 243 heads so no more poor CR. It will also be getting a NNBS intake with throttle body, a drop in CamMotion truck cam (206/210 deg. @ .050- .553"/.553" 115LSA), and electric fans. After a Pat G tune it should make much more power and hopefully not loose, possibly gain, some fuel mileage.(when I keep my foot out of it). I have been doing various mileage checks and getting around 13 city and 15 highway 
Stay tuned and will update thread as I get more info.
