ATT owner thread ?

[Slim Shady]

OK so I understand correctly the ATT in unaltered form is a T4 nd it remachined to fit a T3 ?
Also Dennis has anybody tried bolting one up to a Banks 6.2 Manifold ? Reason I ask is PO of my Dually has a Banks setup for 500$ but the turbo doesn't look to healthy to me. I have no idea how ATT would sit on it but I remember from seeing TD's truck it looked substainlly larger in phyiscal size to a GMx and the Banks is even smaller IIRC than a GM4.

The statement is correct on the unaltered form, The ATT is physically larger in dimension than the GM 8 in length and height I am not sure if the height would fit, the length should work. The mounting base will work, standard T3.

 

[Slim Shady]

I just finished reading the 47 pg origional thread on the ATT. Between that thread and this one I'm sold. I just need to figure out how to finance the purchase, I'm on a limited income. What can I sell? Anybody wanna buy a Ford PU with a 460? Nah, you guys already got better rigs--6.5 diesels with ATTs.

Don

Don, the original ATT A-Team Turbo days were spectacular, a lot of members here contributed. It is because of the people here that the turbo made it at all, they supported and stood behind me when things got really bad. That is why DTR (the truck stop) members get a discount, others don't. I will always owe a debt to the people here whom I call friends, for supporting me.

Members here also (and you know who you are) supported and continue to support me in a much greater way as well. The people here are rare in as much as we all share a sense of morality, and civility, something that a lot of people these days are missing. We truly have the best technical support and knowledge base on the web for the 6.5. I have enjoyed meeting some of you in person and on the phone, I also look forward to meeting more of you in the future.

 

[Big T]

Mileage Decrease w/ ATT?

I don't have before and after figures, but I can compare my '99 Suburban 2500 4x4 with ATT and Heath GL4 to my '95 Suburban 2500 4x4 which has stock turbo and no programming changes. The '95 gets 17 mpg on the highway at 70 mph. The '99 gets about 15.5 mpg at 70 mph. All the other ATT claims are mostly accurate.

I recently towed my 18' Ranger Bass Boat up the front route Hwy 330 to our place on Big Bear Lake. Elevation gain from 1500' to 7100' at the summit. Ambient temps from 70s at the bottom to high 50s at the top. My guess is that the boat and trailer weigh no more than 4,000 lbs. In my '95 I'd have a hard time keeping the temps under control with speed much above 35 mph. In fact it's hard to achieve speed much above 35 mph in the '95. In the '99 I was able to maintain 45 mph with the temp right at 210. Definitely more guts with the ATT. Mileage increase? Ain't buying it. Just not there and the '99 has 3.73 rears while the '95 has 4.10s.

 

[NVW]

What was the 99's mileage before the ATT? Every vehicle responds differently to a mod.

 

[Matt Bachand]

You can't compare 2 different trucks. Just can't do it. Way too many veriables. Brakes, engine, drivetrain, tires, drag, etc....

Can only do before and after on the same truck, hopefully just one mod at a time.

Swap the ATT out of the 99 and put it in the 96. Put the GM-X in the 99. THen record Mileage from both trucks over the next month. Compare those numbers with the current ones. Thats only fair.

 

[Big T]

What was the 99's mileage before the ATT? Every vehicle responds differently to a mod.

Don't know. Bought it in January with the mods on it. I'm only comparing between the two vehicles: '99 with ATT and '95 without. 3.73s vs 4.10s. It's defying all logic and claims.

 

[Matt Bachand]

Don't know. Bought it in January with the mods on it. I'm only comparing between the two vehicles: '99 with ATT and '95 without. 3.73s vs 4.10s. It's defying all logic and claims.

Can't compare two different vehicles. Could be the tune for all we know.

Whats defying logic is saying a turbo that is proven to take less engine power to produce the same boost at a cooler temperature does not increase MPG's.

You should swap the turbos around to see if MPG's gain on the 96. If your 99's MPGS go UP with the GM-x turbo, I'd say your statement has weight, but if MPG's go DOWN with the GM-X, then what would you think?

 

[Big T]

Can't compare two different vehicles. Could be the tune for all we know.

Whats defying logic is saying a turbo that is proven to take less engine power to produce the same boost at a cooler temperature does not increase MPG's.

You should swap the turbos around to see if MPG's gain on the 96. If your 99's MPGS go UP with the GM-x turbo, I'd say your statement has weight, but if MPG's go DOWN with the GM-X, then what would you think?

I'm not swapping the ATT from the '99 to the '95: A) I do not have programming for the '95 that would allow an ATT; and B) I've got a lot better things to do with my time.

 

[Turbine Doc]

BT something unique to your vehicle I think, I've ATT'd 2 vehicles now, both have had mpg gains after the installs, my mpg appears to have gone up yet again on the truck with injector replacement I did a month ago, I've made 2 trips but have not gathered enough data yet to know how much difference there has been, but just by observing fuel gauge and miles traveled it's taking longer to reach the 1/2 tank mark. I've full filled twice now but can't compare numbers as I have not kept at a constant speed to compare.

FWIW ATT will work with a factory program, just not as well as with a reprogrammed chip/computer.

 

[Detroit Dan]

gotta be related to the gearing, that sounds like the only substantial difference in the trucks

 

[Matt Bachand]

I'm not swapping the ATT from the '99 to the '95: A) I do not have programming for the '95 that would allow an ATT; and B) I've got a lot better things to do with my time.

I agree, and without beating a dead horse, or sounding crude, I don't think its fair to say Decrease in MPG from ATT based on your experience.

You may look at things differently, perhaps more correctly, if your 99 was only getting 14-15mpg with the GM-X and was achieving the current 16mpg rate with the ATT. At the same time, consider the thought of your 95 getting 10% better mileage than the fantastic 19 you're getting now.