A-Team Turbo VS CKO-40(hx-40 knock-off)

[THEFERMANATOR]

I know you've said before that two of you are posting under one name, but that "we" thing is freaking me out man!



Myself, I've been trying to find a way to use the PWM signal from the 6.5 PCM to run a PWM driven VVT turbo control, but it is proving to be difficult to fabricate on a part time basis. My work is eating up a lot of time. I have to conduct SAR OPS on a 24 hr basis, run my section of 8 Engineers and oversee an Entire Squadron (100+ trouble makers!) as the Squadron Warrant Officer. Not much time left for cocky to play in the garage! 8 more years to retirement, lots of time to play then.....

But, the idea is something like a HE351VE run off the stock 6.5 PCM.

Neat, clean and fully integrated and controlled by the .cal files in the PCM....

Have you considered teh KISS method to control it? I know they used to ahve VVT turbos that had an external wastegate arm that controlled the vanes. On a set-up like this you could use the stock vacuum canister to control it and hook a spring to it to hold the turbo open. As it applied vacuum it would pull it to the closed vane position which would cause boost to rise, and as it releases vacuum the return spring would pull them to the open position and lower boost. It seems like a simple enough way to control the VVT mechanism via a stock 6.5 PCM.

 

[great white]

Have you considered teh KISS method to control it? I know they used to ahve VVT turbos that had an external wastegate arm that controlled the vanes. On a set-up like this you could use the stock vacuum canister to control it and hook a spring to it to hold the turbo open. As it applied vacuum it would pull it to the closed vane position which would cause boost to rise, and as it releases vacuum the return spring would pull them to the open position and lower boost. It seems like a simple enough way to control the VVT mechanism via a stock 6.5 PCM.

I have and it's kind of a "fall back" position if I really want to make a VGT turbo of some sort work.

I've also thought of a simple turbo master style spring regulated controller regulated by drive pressure. I think there a youtube video of someone using it that way, or at least some type of vgt.

But, where the fun in that?



What I'm exploring is a way to use the PWM signal from the PCM to the motor on the 351. Eliminate the vacuum system all together....wholly "digital" control.

May be beyond my reach, but that's the idea....

 

[THEFERMANATOR]

I have and it's kind of a "fall back" position if I really want to make a VGT turbo of some sort work.

I've also thought of a simple turbo master style spring regulated controller regulated by drive pressure. I think there a youtube video of someone using it that way, or at least some type of vgt.

But, where the fun in that?



What I'm exploring is a way to use the PWM signal from the PCM to the motor on the 351. Eliminate the vacuum system all together....wholly "digital" control.

May be beyond my reach, but that's the idea....

The downside to the turbo master system is a VVT turbo can reach HIGH boost levels without any fuel, just the air the engine pumps through it. It would be like having a turbo brake on all the time everytime you let off the throttle. Installing a solonoid to allow the vanes to go more open at low RPM's would be nice though. If you set the vanes at say 40% for normal driving it would keep the boost down a bit at cruise while still allowing it to reach a good amount of boost. Then put a servo on it to go to full closed for a turbo brake would be nice as well. The key to making a VVT work best though is to be able to vary the vanes from about 80% at idle to about 35-50% at a medium load, and down to the 15-30% range at WOT(to hit about 20 lbs of boost). But for best milage, you need to drop the vanes back to about 15-25% at cruise to get the boost down.

 

[turbonator]

We experienced a similar thing with the double turbomaster we used on the VGT turbo, spiked as high as 30psi, and at cruise we were still boosting sometimes as high as 12psi. At the beginning, when first starting to use it, in low gear (SM465) it was almost uncontrollable. We had to loosen the springs up a lot to allow it to open. This brought our boost down to peaks (WOT) of just over 20psi. The same pump (turned up another 1/4 turn), with a side-mounted H1C, tops out at 12psi. We will use the VGT again, this time will try with a boost actuated (or controlled) pneumatic cylinder. This is partially with the goal of being able to use the exhaust brake feature.

 

[racedaymechanic]

I got the HX40WII Turbo back and It checks out good, I am now trying to get everything I need ahead of time before I start the installation, Im gonna try to make it so I can swap back to GM8 or Ateam without too much fab work, Im down today cause I got my last Wisdom tooth pulled this morning, Im gonna do the battery relocate at the same time, I think that is gonna be a winner

 

[DZZ71]

I just had my Wisdom teeth pulled. Man what a pain that was. The first 3 days wernt bad but after that it was about 2 days of solid pain like Somone was turning a drill bit in my gums real slow.

 

[turbonator]

Sounds great, will be a real treat for all of us to have three different sets of data to compare....well, for us number crunchers anyways. Our idea for multi-testing was turbo specific individual elbows. Somewhat daunting for non-fabbers but doable. Looking forward to seeing your builds and results.....j&j.

 

[handcannon]

I'm also looking forward to the tests and results.

Don

 

[robzombie4551]

now the CKO-40..... the purchaser must be aware that this turbo is not a direct fit-bolt on and requires mods as well to work..and that there is no support available to do so..
1# down-pipe: a person must source out the pieces to build the adapter(90* elbow,2 v-clamp flanges, and one v-clamp, welder) to attach the turbo to a gm down pipe(buddy has already built one and if he chooses may post the pics here)
2# oil supply: the boss on the turbo either needs to have an adapter sourced, or be re-threaded, to accept the gm-x adapter.
3# intake: i am not sure if there is modify/trimming involved, all we can say is that to use the H1C non-gated turbo on our build, there was a fair bit of trimming grinding needed to the cool-side outlet to slip a coupler over it as it was set-up for a holset elbow to go to an intercooler....
4# oil drain: i am not sure if the oil drain needs to be modified in any way to mount the CKO, although with our H1C we had to cut it and use a coupler for it to work... and i do not find any info with RZ's install in that department...5# flange to flange mounting: the CKO( depending on where/who it is sourced through) is a t-3 flange, but i have seen them with the t-4 as well...

These are my posts from the turbo upgrade thread on The diesel Place which starts on page three:

These are pics of the turbo mocked up on the manifold.

To install this turbo you will need to trim 1/2'' off the turbo and 1/4'' off the GM upper intake. I know in the pics it's close but what you see in the pics are not the measurements above. There will be enough room for expansion if you follow those measurements.

You will also have to make a 1/2'' spacer to put between the upper and lower manifold. Unless you would prefer to cut the upper futher back and use silicone hose to make up the height difference.

The oil feed line will need to be tapped for the GM oil feed line fitting, and the oil return requires no mods at all, it's a direct bolt up.

And continues on for a few more pages. Also the vids start on page 13 from the stock chip all the way up to tune 5 on the six banger chip.

after watching videos of the 2 different turbos, i can say that I do not see much difference in the over-all performance of the 2, although i will say that the CKO-40 is not recommended by me for a motor that is not built to handle 18-30psi boost, and is a waste of time to use below 15psi. the ATT is offered for both modified and stock motors, and boosts according to the amount of fuel available and thats it. in our opinion, we are more likely to stick with the non-gated turbos as we have enjoyed great results with our H1C(very comparable to a ATT i would guess) anyways we are not trying to start an emotional debate here, just stating what we have seen/heard to help keep everyone better informed... thanks, jeff&jim

Now you have your right to your opinions, as do I and will set the record straight.

1) What vids were you watching? Are you blind or just biased? The ATT is a chinese made knock off, the same as the one I run.

2) When did the ATT start being offered in two different configurations that makes it a dual purpose turbo? Modified and stock motors?? HUH???

3) The turbo I'm running will work on both stock and modified motors and builds boost at a lower RPM then the ATT. And the hx40 will, like any turbo, only boost according to the amount of fuel available.

4) Why would the HX 40 be a waste of time below 15lbs.??? That is were it performs better than an ATT and spools faster than the ATT. It also spools as fast as a GM8 turbo. The vids don't lie and I think you watched them.
I even posted the use of the HX40 with the stock programming and it pulls to 3,500 rpm before the defuel cuts in. That my friend is proof enough that this turbo is better than any GMX turbo up top and stills spools the same as a gmx down low, and I won't get into the comparisons of any others to avoid a petty squabble.

As far as you not liking knock off turbos, that's your opinion and right. The ATT is from the same communist country as the HX40 is. Anyone, including you should have an open mind and if you don't like knock offs that's cool, but someone who see's the vids and reads the install posts and wants the same turbo but hates K/Os can get a name brand turbo in the same configuration or find one that is close to those specs.

If you want to continue bashing the clones that's fine,do you hate all chinese clones or just the one I use? The real reason I bought that turbo was that it is a less expensive alternative than paying full price for a name brand turbo, or paying the mark up of the ATT which isn't what I wanted in the first place, as it didn't fit the needs of my usage and I was buying a turbo for testing purposes to prove that there are alternatives that can work on the 6.5 other than the non-wastegated turbos out there.

Wastegated turbos spool faster down low and have less recovery time between shifts on a standard trans and that's a fact and one of the reasons I went the route I did.

As far as you saying that I wired my wastegate shut and saying why bother running a gated turbo, the only reason I unhooked the hose to the W/G [I never ran it wired shut] was to see why I wasn't boosting as high as I had it set for and thought the intercooler was to big or there was a leak somewhere. After finding that there was no leak and that the wastegate spring had relaxed, I readjusted it and have had no furthers issues.

ALL THIS IS IN THE TURBO UPGRADE THREAD and was posted. You either didn't read it or chose to not read it all. In the future please get your facts straight, or don't quote what you haven't read or don't remember.

I would be happy to help you by listing any posts I have made and which page and post they are in the future so as not to put out any misinformation.

After all isn't sharing and getting the truth out while helping others what this is all about??

Just let me have the same oppertunities as others to share what I have done so others can make up their own minds without bias or personal attacks on said modifications.

We all have different wants and needs out of our trucks and NO ONE TURBO CAN MEET ALL NEEDS OF ALL TRUCKS OR INTENDED USES.

we are not trying to start an emotional debate here, just stating what we have seen/heard to help keep everyone better informed... thanks, jeff&jim

That's all I'm doing also.
Please don't take this post out of context as I'm not looking for any trouble with anyone. PERIOD.
I've stayed off this site for awhile. I'm just pointing out some facts and some opinions as others have, please lets keep it civil with no name calling or other inuendos.:thumbsup:

 

[turbonator]

These are my posts from the turbo upgrade thread on The diesel Place which starts on page three:
And continues on for a few more pages. Also the vids start on page 13 from the stock chip all the way up to tune 5 on the six banger chip.


Now you have your right to your opinions, as do I and will set the record straight.

1) What vids were you watching? Are you blind or just biased? The ATT is a chinese made knock off, the same as the one I run.

2) When did the ATT start being offered in two different configurations that makes it a dual purpose turbo? Modified and stock motors?? HUH???

3) The turbo I'm running will work on both stock and modified motors and builds boost at a lower RPM then the ATT. And the hx40 will, like any turbo, only boost according to the amount of fuel available.

4) Why would the HX 40 be a waste of time below 15lbs.??? That is were it performs better than an ATT and spools faster than the ATT. It also spools as fast as a GM8 turbo. The vids don't lie and I think you watched them.
I even posted the use of the HX40 with the stock programming and it pulls to 3,500 rpm before the defuel cuts in. That my friend is proof enough that this turbo is better than any GMX turbo up top and stills spools the same as a gmx down low, and I won't get into the comparisons of any others to avoid a petty squabble.

As far as you not liking knock off turbos, that's your opinion and right. The ATT is from the same communist country as the HX40 is. Anyone, including you should have an open mind and if you don't like knock offs that's cool, but someone who see's the vids and reads the install posts and wants the same turbo but hates K/Os can get a name brand turbo in the same configuration or find one that is close to those specs.

If you want to continue bashing the clones that's fine,do you hate all chinese clones or just the one I use? The real reason I bought that turbo was that it is a less expensive alternative than paying full price for a name brand turbo, or paying the mark up of the ATT which isn't what I wanted in the first place, as it didn't fit the needs of my usage and I was buying a turbo for testing purposes to prove that there are alternatives that can work on the 6.5 other than the non-wastegated turbos out there.

Wastegated turbos spool faster down low and have less recovery time between shifts on a standard trans and that's a fact and one of the reasons I went the route I did.

As far as you saying that I wired my wastegate shut and saying why bother running a gated turbo, the only reason I unhooked the hose to the W/G [I never ran it wired shut] was to see why I wasn't boosting as high as I had it set for and thought the intercooler was to big or there was a leak somewhere. After finding that there was no leak and that the wastegate spring had relaxed, I readjusted it and have had no furthers issues.

ALL THIS IS IN THE TURBO UPGRADE THREAD and was posted. You either didn't read it or chose to not read it all. In the future please get your facts straight, or don't quote what you haven't read or don't remember.

I would be happy to help you by listing any posts I have made and which page and post they are in the future so as not to put out any misinformation.

After all isn't sharing and getting the truth out while helping others what this is all about??

Just let me have the same oppertunities as others to share what I have done so others can make up their own minds without bias or personal attacks on said modifications.

We all have different wants and needs out of our trucks and NO ONE TURBO CAN MEET ALL NEEDS OF ALL TRUCKS OR INTENDED USES.



That's all I'm doing also.
Please don't take this post out of context as I'm not looking for any trouble with anyone. PERIOD.
I've stayed off this site for awhile. I'm just pointing out some facts and some opinions as others have, please lets keep it civil with no name calling or other inuendos.:thumbsup:

the ATT has been marketed like this since the beginning, motor does not require modifications.... and why update turbos at all if the owner is just keeping it at 15 psi boost, the gm-x does that.... IMO an hx-35 can handle all those duties, why go big to stay small was my point... i am not trying to argue or make trouble, i was just wanting to help make aware all the guys that were running out and buying CKO-40 turbo, that it is not bolt on and requires mods... and hey lets be honest here, which turbo is the most copied in the world, holset for sure... i would be curious to see 10 different holset knock-off turbos from 10 different companies and compare the quality.... sure the ATT is a copy too, but is copied off mitsu.. dont see many mitsu knock-offs out there, and i have looked... alot.... i am just saying that maybe being only one or two turbos, the company has more stringent quality control... i dont even know which company it is anyways... i am glad you came in here and corrected me rob, sure i missed some stuff, but have you went in that thread to find anything? damn near impossible...LOL...

 

[great white]

Still waiting on an HE351VE on a running engine with referenced computerized controls.

fo shizzle......



Not enough loose cash to buy one myself right now.

 

[Slim Shady]

Well at least I can post here, banned over at the Place. You should be glad that this site is more open minded than your home. And I would have doubts that the record can be set straight by one involved in pursuing his agenda.:???:

The ATT is not an off the shelf clone as your HX40 knock off or the HX40II knock off which by the way takes considerable fabrication to use and comparing the smaller housing to the A-team is not an equal comparison. I paid to have the A-Team turbo made to specifications that were considered safe for our weak blocks three years of testing before selling one and now turbos with over 50000 plus miles of heavy service on them. The turbo does not require a modified block or an optimizer engine to give a buyer a long and usefull service life and cause no harm to the engine.

It is easy to slam something when one is unaware of what type of considerations went into the design to make the turbo effective and safe for our blocks. I have heard of more than one 6.5 comming apart after a period of running it with 20 psi of boost.

The A-Team Turbo is in "my opinion" the best choice, I have technical support, parts if needed, and clearly give a purchaser a quality product that has been field tested and proven safe and durable.

The price? considering the amount of production machining that goes into the turbo. All parts are interchangeable with any other A-Team Turbo. Down pipes fitt all turbos and their are no surprises during the install.

The turbo works off the heat generated by the fuel supplied to the engine not off of the cfm of exhaust gas exiting the manifold. It is easy to make summations based on what one has "HEARD or READ", that is not comparison.

I contacted RacedayMechanic and will be supplying the ATT to him to compare to his HX40II knock off, Not the HX40 clone. Matuva alos has a few ATT turbos to compare to the HX40II knock off. Once again the HX40 II is a smaller housing not the same size as the A-Team. These individuals are in my opinion qualified to make comparisons. Supply War Wagon with the HX40 as he can make a comparison on his truck. I am ponying up to compare lets get War Wagon a HX 40 to use and abuse like he has the A-Team Turbo.

My thoughts on the waste gated turbo? Anything that is a fit all or needs a waste gate to boost in the lower rpm loses efficiency when the waste gate opens. Turbos should work from heat energy and only work when needed not work all the time. Boost numbers are something that people are stuck on. More is not necessarily better and at cruise having a less restrictive housing saves fuel, which is not cheap.

Only the end purchaser can justify which turbo is their best turbo, ALL TURBOS have trade offs NONE ARE perfect.

 

[great white]

How about we just all wait for raceday to do his thing and leave the "back and forth" at the door for now?

 

[littleboy]

Slim .... you have an interesting write up! The hx40 is most efficient from 0-20 psi. At 30 psi the hx40 is all in. Any boost over 30 psi just makes more heat an the turbo is out of it's map. And in all of our testing turbos the outside diameter of the housings means nothing. It is all about how they are designed inside an to me it's more about air volume than actual boost numbers! I personally have never had my paws on a chinese knockof turbo. We only use genuine Holset turbos! I don't know how they compare to each other .

 

[robzombie4551]

i am glad you came in here and corrected me rob, sure i missed some stuff, but have you went in that thread to find anything? damn near impossible...LOL...

No problem. I know how hard it is to regurgitate all the info in that thread. It's hard to find all the info that pertains to what you're looking for or what was said when and where in that thread.

That's why I pointed it out,not to start anything,just to get what I said straight.

My only point of why the HX40 [real or clone] is a good replacement from stock to modified is that it is wastegated and spools down low [holesets are known for their quick spooling]with stock fueling, and can stay on the truck even as you continue to get more money to change/upgrade things like tunes IE; more fuel and other mods without having to keep buying specialized turbos that only works in a narrow parameter/rpm level.

The HX35 might be a good stock replacement type turbo at best and wouldn't be an ideal candidate for anything more.

I will be testing an ATT soon and will also post comparisons of that and the turbo I'm running now . Comparing the ATT to an HX40II might be unfair as the turbo is smaller then the ATT and would prove that down low the HX should win out and up top the ATT should win out.

Bring on the tests we all love more info, and comparisons!!!

Holesets work so well on the 6.5 because of the quick spooling that holesets are famous for and on a 6.5 pushing 20/25lbs. of boost they are only cruising and are at their peak effiency at that boost compared to 40lbs. or more that the cummins guys run at where effiecency is cut almost in half.

 

[racedaymechanic]

I am in the process of putting the HX40II on as we speak and one thing I will make real clear there is some work to make this Turbo fit, I am at the point now of collecting all of the extra hardware to make this happen, my goal is to make as few changes to the actual engine and truck as possible, I just don't want to make this too complicated (I tend to go alittle overboard on details lol) I want to be able to go to the ATT without making too many changes in the basic, I am using a -10 an drain setup for the turbo and staying with the stock feed line I have a male metric to female pipe reducer to do that, ill get into more details with pics shortly

 

[JiFaire]

Thanks for the update, Bruce. I trust you, Alastair, or WarWagon to cleanly and clearly present the unbiased results of the comparison...

Jim

 

[Slim Shady]

Slim .... you have an interesting write up! The hx40 is most efficient from 0-20 psi. At 30 psi the hx40 is all in. Any boost over 30 psi just makes more heat an the turbo is out of it's map. And in all of our testing turbos the outside diameter of the housings means nothing. It is all about how they are designed inside an to me it's more about air volume than actual boost numbers! I personally have never had my paws on a chinese knockof turbo. We only use genuine Holset turbos! I don't know how they compare to each other .

[

,

There are many aspects to a turbo and you are correct that the internal design makes the housing more than the housing size. Cross section or /AR does not tell the whole story, The internal passage design wheel configuration and other factors play a more important role.

The A-Team rotating assembly has all of the internal parts balanced separately then assembled and balanced as a rotating assembly at high speed to ensure a smooth and durable assembly. I have also personally run my A-Team at extended turbine temps of 1300 to 1400 degree for more than five minutes at 20 psi boost without any failure. I am not sure how other knock of turbos would survive under these types of temps.

Also the Mitsubishi turbo that was the basis for the design is a very high end and very durable industrial quality turbo made for extreme conditions. You don't see many Mitsubishi turbos just floating around. Durability and functionality was what the goal was with the A-Team Turbo, I think we have proved that 50000 hard miles on a A-team will not kill it. I also service the turbos and have parts available for them, I am not just selling a turbo and saying good luck to you.

Lets talk on the Cummings I have an extremely good machinist, PM me. Lets get a A-Team mounted on a Cummings and see what it does. I am up for that

I think that Bruce, Alastair, or WarWagon would be the most unbiased to cleanly and clearly present the results of the comparisons. I look forward to contributing a turbo to compare to the HX40. I think there is not enough long term testing to warrant giving the HX40 knock off the same durability rating as the A-Team Turbo. That is an earned reputation in my opinion.

 

[turbonator]

[

,

There are many aspects to a turbo and you are correct that the internal design makes the housing more than the housing size. Cross section or /AR does not tell the whole story, The internal passage design wheel configuration and other factors play a more important role.

The A-Team rotating assembly has all of the internal parts balanced separately then assembled and balanced as a rotating assembly at high speed to ensure a smooth and durable assembly. I have also personally run my A-Team at extended turbine temps of 1300 to 1400 degree for more than five minutes at 20 psi boost without any failure. I am not sure how other knock of turbos would survive under these types of temps.

Also the Mitsubishi turbo that was the basis for the design is a very high end and very durable industrial quality turbo made for extreme conditions. You don't see many Mitsubishi turbos just floating around. Durability and functionality was what the goal was with the A-Team Turbo, I think we have proved that 50000 hard miles on a A-team will not kill it. I also service the turbos and have parts available for them, I am not just selling a turbo and saying good luck to you.

Lets talk on the Cummings I have an extremely good machinist, PM me. Lets get a A-Team mounted on a Cummings and see what it does. I am up for that

I think that Bruce, Alastair, or WarWagon would be the most unbiased to cleanly and clearly present the results of the comparisons. I look forward to contributing a turbo to compare to the HX40. I think there is not enough long term testing to warrant giving the HX40 knock off the same durability rating as the A-Team Turbo. That is an earned reputation in my opinion.

i am curious to see the differences in the turbines wheels slim, i mean the changes you had made between the mitsu and the a-team, do you have pics of the before and after?

 

[WarWagon]

the ATT has been marketed like this since the beginning, motor does not require modifications.... and why update turbos at all if the owner is just keeping it at 15 psi boost, the gm-x does that.... IMO an hx-35 can handle all those duties, why go big to stay small was my point... i am not trying to argue or make trouble, i was just wanting to help make aware all the guys that were running out and buying CKO-40 turbo, that it is not bolt on and requires mods... and hey lets be honest here, which turbo is the most copied in the world, holset for sure... i would be curious to see 10 different holset knock-off turbos from 10 different companies and compare the quality.... sure the ATT is a copy too, but is copied off mitsu.. dont see many mitsu knock-offs out there, and i have looked... alot.... i am just saying that maybe being only one or two turbos, the company has more stringent quality control... i dont even know which company it is anyways... i am glad you came in here and corrected me rob, sure i missed some stuff, but have you went in that thread to find anything? damn near impossible...LOL...

So If I use a smaller turbo that chokes at 14 PSI about the time the starter disengages then I should be happy with only 14 PSI? I am here to tell you I HATE the GM3’s 14 PSI hard limit vs. an ATT 14 PSI. Let’s compare the exhaust back pressure for an ATT at 14 PSI to a GM4 like Buddy did and I reposted here with permission.

http://www.thetruckstop.us/forum/showthread.php?33098-Info-on-why-you-would-want-an-A-Team-Turbo

The A Team Turbo generates 14 PSI of boost (16.8psi exhaust) with less back pressure than a GM3 (19.6psi exhaust)

The hard limit of a GM3 before it generates more heat than boost is around 14 PSI. More fuel just turns to smoke and most people start to squirm with the EGT’s seen. After all the EGT gauge goes to 1600…

So at 2200 RPM the GM3 turbo is simply done and the engine feels like a boat anchor above 2200 RPM. With the ATT and the lower boost, 13 PSI, due to B99 fuel I am running the engine can breathe above 2200 RPM and will pull till redline. I have had the ATT at 18 PSI and pulling strong on #2 diesel. So the ATT has potential for more boost, however, even when not used it is still allowing more power than a GMx due to less backpressure, etc.

Engine RPM vs. boost is a major change with small vs. large turbo’s. The engine with no throttle will generate 6 PSI of boost on a GM3 at 2000 RPM – in effect a turbo exhaust brake. 6-14 PSI and popping the wastegate open doesn’t take much throttle at all! The GM3 is boosting from idle till it chokes at 2200 RPM. The ATT starts boosting around 1700 RPM with the tach moving up fast from there. The boost will drop to near zero if you take your foot off the throttle.

This is why 14 PSI is just a single number when MPG, HP, ECT, EGT, MPH are also important and to some MPH and MPG are a lot more important than what # the boost is at.

What exactly is the point of asking the difference between the ATT and the Mitsubishi turbo that was the basis for the design? Dennis is not selling a Mitsubishi turbo! Rather a knock off or whatever you want to call it with changes specific to work on our 6.5. This knock off is up to Dennis to control the quality of and is what a lot of testing was done on. This is the turbo that anyone can buy and what we should be concerned about. Differences between them, if any, are not relevant for the ATT vs. GM3 vs. Holset. Quality and consistency of the ATT turbo is relevant vs. quality/performance many knock offs of a Holset or GM8.

I have pushed the ATT to 1550 EGT sustained while tuning and only burned the turbo blanket some. We changed the tune, however. I still have a running engine making EGT only one of many factors that can predict an engine meltdown. Different timing with lower EGT may be an issue. We were doing 55MPH with the ATT when we hit EGT’s that high. With a tune change due to the 6.2 precups we were able to still do 55 MPH but with lower EGT’s. The GM3 going that hot was at ~40MPH. I noticed the GM3 did discolor the paint on the floorboard where the downpipe goes past.

IMO when I cranked up the fuel and stomped it from a stop I could smoke a GM3 for about 3 parking spaces. With the ATT I could smoke it for 6 Parking spaces. Keeping the RPM a little higher for the bigger turbo is about the only downside some may need to get used to. Searching for another turbo to be in the middle is starting over and not a kit. So quality of the sourced turbo will need to be refined and getting all the right parts in one place at the same time… Well lack of proper parts in the same place is why the Holset wasn’t tested by us over Thanksgiving.

It would be interesting to get an answer to the question of how it stacks up.