To ATT or not part II Technical Discussion Only ?

[tazz]

Go figure, you can't even trust google translate and yes that is what I meant.

 

[Woody35]

google translate always screwed up my assignments in french class so i wouldnt really try it at all. kinda like if you try to translate different english words that are from different regions and have different meanings.

 

[NoDak]

I must say fella's... this is all I've learned from this thread thus far;
1. ATT guys are stand-up, they gave the fella a refund!
2. We still don't know what's wrong with subject vehicle, I'm pretty sure something isn't right, we just haven't figured it out yet.

I'm sure we are all curious about #2, but if TAZZ finds and tries some other turbo that works, you have to ask "why does it work"? At that point, we may still not know what may be wrong with the subject vehicle.

As for the fella who talked about the cost... I have to admit, I have two ATT's and I got them for free. One has about 39k miles, the other effectively zero miles as we are still sorting out wiring issues. The '95 with the ATT has over 39k miles on it now. The ATT took me from 14.5 mpg year-around to 17.1 mpg year-around. At $4.05/gallon, that takes me from $0.2793/mile to $0.2368/mile, or saves me $0.0425/mile. After 39,000 miles that is a total savings of $1,657.50!!!! Thus, two free ATT's. If you take into account that I had to replace one of the old turbos, the savings to date would pay for the one turbo, two KD exhaust setups and darn near the balance of two KD programs (one chip and one reflash).

I don't have a smoke problems and I'm running the old flat stock air filter. And I really gotta put these new injectors in that '95.... Yikes, they're getting close to 125k miles!!

Good night from one who is still curious....

guten nacht!! or would it be... guten morgan!!

 

[tazz]

WOW, how many times do I have to say it, THERE IS NO PROBLEMS WITH MY TRUCK, plain and simple. The fact is the turbo was just not a match for my truck, need I say anymore.

 

[Paveltolz]

WOW, how many times do I have to say it, THERE IS NO PROBLEMS WITH MY TRUCK, plain and simple. The fact is the turbo was just not a match for my truck, need I say anymore.

Not in my opinion there isn’t. It’s your truck, other’s have driven it and the one mechanic in the country who seems to understand the 6.5 (joke folks, easy now) has confirmed that opinion.
I’ve said it before, writing is the worst form of communication as it is one way, subject to interpretation of the reader and not everyone, me either, is so good at it so as to avoid the misunderstanding by the reader or able to gauge the emotional impact of what was written…then there’s the multiple languages used by our membership. Now add emotion, personal baggage and whatnot to the reader’s day and it very easy to pull an insult from the text that just wasn’t there or intended.

Also, there's no such thing as a perfectly good truck, just like there's no such thing as a perfectly good airplane (which is why I have no problem leaving them in flight). Bound to be a few mismatches out there that just don't work be it driver, mechanical or set up. Can’t fault others for wondering what possible mismatch with this application was but I have to trust Tazz, Kenny et al that the truck is fine.

 

[635]

WOW, how many times do I have to say it, THERE IS NO PROBLEMS WITH MY TRUCK, plain and simple. The fact is the turbo was just not a match for my truck, need I say anymore.

I had the ATT on my truck for quite a while also. It did work great, and gave a ton more power. I saw over 24 pounds of boost with the ATT when it was pulling hard! BUT, our highways aren't set for higher speeds, in the greater Seattle area. I've got 60mph zones around here for miles. 60mph gave me about 2 pounds of boost, with the ATT. My propane came on, with just a whif of propane at 2 pounds of boost and up to 2 cubic feet per minute at 20 pounds of boost. And my WMI didn't come on until 6 pounds of boost. I went back to my GM-8 where I had enough boost at freeway speeds to get the propane and WMI working for better mileage.

But one has to make sure everything is in proper working order with either turbo. Injectors, air intake system, timing, and exhaust!

 

[CtChevy427]

Since the technical merit of this thread has run its course in the technical forum, and digressed into OT subject areas, this thread has now been moved to the OT area of the forum.

 

[Turbine Doc]

Since the technical merit of this thread has run its course in the technical forum, and digressed into OT subject areas, this thread has now been moved to the OT area of the forum.

TTS family :grouphug: now that the furvor has died down a little we are reopening this discussion as it does contain some technical merit, we ask that you curtail yourself from the shall we say "spirited discussion" that was in this thread http://www.thetruckstop.us/forum/showthread.php?30382-To-ATT-or-not (complete & unedited) that was copied for this part II continuation of it.

Summary: Tazz asked about a turbo, installed ATT, it did not work for him, money refunded to Tazz.

Post summary Tazz is running a GM turbo and is happy with it, may be going to a HX derivative.

The turbo has been returned in good working condition & is being tested on Slims truck without issues thus far.

In all of this, it was discovered that there has been a design change to the turbo that was identified on followup of this turbo and maybe 4 others from last batch produced by the overseas supplier, that apparently created some issues for some trucks and no issues on other trucks where turbo from same batch has been successfully installed. Anyone who has an ATT issue needs to contact Slim Shady ASAP to resolve issue.

Variations to the norm from the earlier batch of turbos:

Some trucks reporting high EGT, for valid data point Slim needs to know levels of EGT and truck configurations high is not a quantitative # to go looking for answers with.

Some report lag as an issue, how much lag in some span of time, does it stay "laggy" throughout the range, or get bettter after X rpm?

Smoke reported, how much, and color greish haze or heavy black insect fogging smoke, a puff then clearing or constant never clearing.

All programs including stock, worked with original ATT, some work better allowing for full fueling & grunt potential of ATT, this may not be the case with larger housing ATTs



In the original post there were some very incorrect assumptions being made regarding the intent behind asking these probing questions; it was not to discredit the posters observations, but rather to drill down into finding out what was happening in this installation.

Though some have represented actions of staff shutting down the original thread as protection of a certain idea or concept, that is wholly incorrect, it was not until the civility had broken down was it deemed necessary to lock down the thread. Although we encourage free flow of discussion, civility will be maintained.

A little more leeway is given in the OT areas, so if you feel the need to "spiritedly" vent displeasure, take it there, but stick to fact not innuendo, if you are not directly involved your opinion does not carry much weight and will be treated as such if going overboard with your zeal in way which you let your opinion be known.

Lastly I know I will not be able to convince some who have their minds set, but other than to help a friend, I have no vested commercial interest in this entire discussion.

 

[Turbine Doc]

Okay guys as you can see a lot of work for civility sake, thread open please keep discussion to tech talk.

 

[3500GMC]

Has there ever been a 'compressor map' published or released?

 

[WarWagon]

As posted in my excessive smoke thread with the ATT, I found a issue that was causing the smoke. This was after dropping the Banks exhaust for a 4" exhaust and K47 install. Several tunes including the factory tune were still getting me excessive smoke. A 15 PSI Walbro did not change the smoke.

After replacing the fuel tank and partially plugged tank sock the smoke went from excessive to 'normal' as in not visible over 2000 RPM. I feel a GMx turbo would have covered up this issue as the tank failure and plugged sock in the pickup truck did not result in smoke with it's GM3. A restriction to the IP appears to muck it up fairly well.

Not saying the other truck had this issue. I am saying I had this issue and others can learn from it.

After testing the turbo at altitude 4800' I found that the EGT with a hotter tune goes up 200 degrees WOT, but, the smoke was not an issue with altitude changes starting from 2000'. I will go higher in testing later but this run came up now... A simple switch flick to a less hot tune dropped the EGT's. :hihi:

 

[JiFaire]

As posted in my excessive smoke thread with the ATT, I found a issue that was causing the smoke. This was after dropping the Banks exhaust for a 4" exhaust and K47 install. Several tunes including the factory tune were still getting me excessive smoke. A 15 PSI Walbro did not change the smoke.

After replacing the fuel tank and partially plugged tank sock the smoke went from excessive to 'normal' as in not visible over 2000 RPM. I feel a GMx turbo would have covered up this issue as the tank failure and plugged sock in the pickup truck did not result in smoke with it's GM3. A restriction to the IP appears to muck it up fairly well.

Not saying the other truck had this issue. I am saying I had this issue and others can learn from it.

After testing the turbo at altitude 4800' I found that the EGT with a hotter tune goes up 200 degrees WOT, but, the smoke was not an issue with altitude changes starting from 2000'. I will go higher in testing later but this run came up now... A simple switch flick to a less hot tune dropped the EGT's. :hihi:

How did you find the restricted fuel problem, WW? Did you plumb in a pressure gauge before the IP?

Glad you got rid of the smoke issue, BTW ... I'll be interested to see how you make out at altitude; there have been a few guys with non-wastegated turbos that has issues in the high country.

 

[matuva]

We had a truck with a smoke issue too. Not a big issue, but enough to make the customer a bit anxious.

This problem has been solved with the new CAI sold by S&B/Bill Heath vs the K47.

Now we just have a puff of smoke when flooring the pedal, and clear after. On this same truck, I had to change the Optical sensor on IP. I
took the opportunity to do the optical bump, which did lower a bit more the smoke emission.

 

[WarWagon]

How did you find the restricted fuel problem, WW? Did you plumb in a pressure gauge before the IP?

Glad you got rid of the smoke issue, BTW ... I'll be interested to see how you make out at altitude; there have been a few guys with non-wastegated turbos that has issues in the high country.

The wax plugged fuel filters, junk piling up in the FFM, and engine miss was starting to get bad. So I dropped the tank to check it and check the sock. This is where I discovered the restricted sock and mess in the tank. Gauge readings for fuel pressure at idle and in neutral were good no readings taken under load.

You can run a GM3 out of air at altitude.

I did see a 200 degree change in the EGT from 2000' to 4800' hitting 1400 degrees. A tune change to a less aggressive tune brought EGT back to 1200. The smoke was not a concern with the tunes. I plan to push it harder and higher with a Payson pull later this month.