A-Team Owners

[Slim Shady]

Well finally getting around to having a forum. I would like to get input from owners so that potential buyers can get information and questions answered. Making a decision to purchase a turbo can be daunting. I would also like to discuss tunes from different vendors what you have seen and how the various tunes have performed.

 

[WarWagon]

Got a couple mountain pulls around here that have sent three 6.5 engines to the scrap yard. (one for cooling fan clutch failure, one for #8 injector failure, and one for wearing out - copper seen in main bearing shells.) These all failed as a result of working hard to climb a 6 mile 10% grade and other grades on our parts route I once ran in AZ.

As part of this parts route I run The Beeline, Highway 87, from the 202 to Payson. The light at the Shell station is always red and is the start of this part of the journey. Midway through this section is a dump that is the only light before Fountain Hills. The light usually screws me and turns red stopping me from 65MPH. I am happy if I can get back up to 65 MPH due to the constant steady climb from this light to the Fountain Hills light. It is 17 Miles from the Shell station to Fountain Hills. Then the real mountain pulls start. This is with my 1993 GMC ECLB with both a 6.5 and repowered with a 6.2 after the 6.5 failed. The rear end is a 4.10 and 62 MPH is peak engine torque around 2200 RPM. No real difference between the engines turbocharged. 3MPH top speed is all I could ever see with the MPG being the same. 6.2 was 3MPH slower due to precups. The 1993 with 1/3 turn on the IP screw and 14 PSI of boost on the GM3. In other words all I can do to wring every HP out of it. 4" exhaust on both rigs.

So from the dump light to Fountain Hills light I have a comparison.
1993 K2500 ECLB pickup GM3 vs. 1995 K2500 Suburban w/ ATT.

1993. Would be lucky to hit 70 MPH on any part of this road with a 28' trailer and 65 MPH tops with another 24' trailer I used. Several hills would cause me to hit 62 MPH flat out. Load in the trailer made a difference in MPH. The 24' trailer was 5 MPH slower due to wind drag, misaligned tires, or something weird. Fan may or may not be locked in AC usually on med. The fan would run in this stretch at some point.

1993 Summery:
28' trailer, empty, 70 MPH max and unable to maintain 65 MPH Minimum. Fuel is all the GM3 can handle.(EGT and smoke limit fuel as well as 7.5 MPG average.) This is the section between the dump and Fountain Hills. 90-105 degrees out same results. It will outrun the 1995 in town unloaded.


Next is a 1995 suburban I purchased with a blown engine. It blew the engine on the hill just before Payson with the last owner. I replaced the engine and turbo due to the debris the shattered piston and coolant in the oil ran through everything. It has a 3.73 rear end and same tire size as the 1993. It has a 6.2 engine complete with 6.2 heads. DS4 IP and new injectors. ATT turbo with blanket and 3" crossover. 4" exhaust. Buddy's tune and a fairly hot one at that.

Went to the dump on a 110 degree day with the 28' trailer. It was 112 when I arrived in Fountain Hills. When I pulled out and hit my favorite light I was able to hit 70 MPH where the 1993 would still be in 3rd gear below 60. Lift pump had failed in the 1995 - in fact stranded me at the end of the run. Even with the lower rear end gears I had more power available and did not have to run this stretch WOT like I do the pickup. The fan was locked up and the AC on high.

1995 Summery:
28' trailer empty, I backed out at 75 MPH. I could maintain 65 MPH and take it to 70 wherever I wanted to. Loaded it will beat the pickup to 70 MPH. Takes longer than 1/4 mile to do so... Slower in town from light to light than the 1993 unloaded. Course it is a heavier suburban with 3.73's.

I do not have other test results with the 1995, like the 1993's 43MPH WOT pull on the 6 mile 10% grade.