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I have been out of the office for a few days, so I haven’t been able to stay up to speed with you guys and your questions. I thought it might be better to pull this out into a fresh thread.

First of all, let me address the issue of t-tapping the TCC wire. The Allison TCC lock-up signal is PWMed in a 3-stage duty-cycle modified event as the TCC goes through its lockup phase. By sensing the BEGINNING of this process, we can start removing fuel before the TCC is actually engaging. The information that is available on the CAN-bus is a simple digital indication of whether the TCC is locked or unlocked. That signal occurs too late for any meaningful use related to fueling to take place. Thus the only way to effectively de-fuel during TCC lockup is to grab the signal from the TCC wire.

I’ve discussed dyno methodology many times before in various forums, and I am almost certain that I have done so in TheDieselPlace forums at one point or another, but for the benefit of all, here is a brief description of how we do dyno testing and how it compares to most of the rest of the world. Our chassis dyno testing is performed as a load test. The vehicle is held in direct drive with the torque converter locked (assuming it is an automatic) and accelerated to a given engine RPM close to the engine redline. Load is applied to the rolls such that the engine will be held at that RPM while the operator applies wide open throttle (WOT) (of course for those that are paying close enough attention, “throttle” is a generic term and is actually a misnomer when applied to diesel). The vehicle is held at this RPM for at least 10 seconds. Then more load is applied to the rolls so that engine RPM is pulled down to a lower point. Our testing is usually done in increments of 100 or 200 RPM depending on how much data we need to accumulate for a given test. The engine is then held at the new RPM point for at least 10 seconds. This process if followed all the down to the lowest point in the test. Usually our goal is to achieve an RPM below the torque peak. Sometimes we are limited by what the vehicle electronics will allow before forcing a downshift with an automatic. During the entire test, we are gathering a huge amount of data including horsepower, torque, multiple temperatures and multiple pressures. Each step is at least 10 seconds long so that we can use a clean portion of data from the middle of the sample group, allowing all readings to stabilize before considering it valid data.

The majority of our Duramax testing has
 

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So...... Have you hooked up two trucks with different programmers (Edge, Bullydog, Van_Aken, Diablo, Duramaximizer..ect) and run them loaded to compare? I would like to see several "real world" tests. I agree with you about the Dyno's not showing exactly what is there or not. A real world test would be extreamly direct...if it was fair.


Burner---------->
 

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So for those of us that have already addressed the Allison torque holding issues, will the race box be competitive in 1/4 mile ET, or will it also be focused on towing and sustained loads?


I believe that Banks makes a quality product, and would be the first in line to buy one, but I am looking for the most HP on #2, and my money will go to the company that supplies that in the most refined package. I know several others feel the same way, and there is a solid market for a race box.
 

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Burner said:
So...... Have you hooked up two trucks with different programmers (Edge, Bullydog, Van_Aken, Diablo, Duramaximizer..ect) and run them loaded to compare? I would like to see several "real world" tests. I agree with you about the Dyno's not showing exactly what is there or not. A real world test would be extreamly direct...if it was fair.


Burner---------->




Soon as I can land that Allison software...


The test program is written, and I can step down from 60mph vehicle spped, but any higher and the Tech 2 "punts"








Peter,





If I understand correctly, the TCC signal does not affect the fueling curve of the 6 gun once lockupis acheived. My reason for asking is that the ATS transmission controller has a "force on" for lockup which I believe is 100% duty cycle.


My testing to date has shown repeatable results and is done on a level playing field. The vehicle stabilizes at 40 mph (WOT) and then when all is normalized, it is allowed to accellerate to 75mph in 12 seconds simulating the real world feat of pulling a trailer up to speed. I have seldom found a hill or load that can drag a "chipped" Duramax down decisively, let alone hold a gear to much below 2,000 RPM...
 

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Peter,


Thanks for the info.
 

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Peter,


Yes thank you for providing more info!
 

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Would it not be better to "load" the trucks stock? What good is it "locking" them into a gear? Hooking up an artificial "lock-in" would not mimic a "real world" senerio, so what good is that? I think that you're on the right track pulling "down" on the truck....but the Allison should be allowed to shift "as is". I think that you might gain something from John Kennedy. I think that John is simulating a loaded truck @ take-off and then applying resistance to simulate a hill and/or wind as well as a step-down simulation.


From what I understand the Allison program will only relase and downshift if the TQ and speed (HP @ X RPM) drop past a given point. Help me out here, am I missing something?


Thanks,


Burner-------------->
 

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Peter,


If the only info available on CAN-bus is a digital indication of whether the TCC is locked or unlocked, then how does the Edge Attitude know how much (in %) the tranny is slipping when it's not locked? As I understand it, the Juice backs off the fuel based on the % slip, not just whether it's locked or unlocked.
Edited by: Matador
 

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Burner said:
Would it not be better to "load" the trucks stock? What good is it "locking" them into a gear? Hooking up an artificial "lock-in" would not mimic a "real world" senerio, so what good is that? I think that you're on the right track pulling "down" on the truck....but the Allison should be allowed to shift "as is". I think that you might gain something from John Kennedy. I think that John is simulating a loaded truck @ take-off and then applying resistance to simulate a hill and/or wind as well as a step-down simulation.


From what I understand the Allison program will only relase and downshift if the TQ and speed (HP @ X RPM) drop past a given point. Help me out here, am I missing something?


Thanks,


Burner-------------->

 

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Discussion Starter #10
Amric,
I don’t have a lot of detail about the Race Box at this point, but since the Six-Gun has many built in protection features that are good for all around use, I imagine that the Race Box by definition will forgo much of that and be designed to deliver all-out power without regard for safety.

Kennedy,
You are correct, once the TCC is fully locked, that signal is not used to modify the fueling in any way. At that point, the only modifiers would be slippage detected anywhere in the transmission (a result of an excessive calculated differential between input speed and output speed) or fuel limiting based on exhaust gas temperature. I don’t think there would be any conflict between the Six-Gun and the ATS controller that you mention.

Burner,
Granted, the testing that we do may not be “real world”, but it is clearly worst-case scenario. It allows us to know beyond a shadow of a doubt what the performance of the vehicle will be under the worst of conditions. By testing in this manner we find all the weak spots, slippage points, etc., and we know what is safe for the long term as opposed to a quick flash snapshot. We manipulate the trans to be able to achieve readings lower in the RPM band. This makes testing on an automatic similar to the type of results you might get with a manual without the hassle of slipping the manual clutch. If we didn’t manipulate the trans, we would probably never see the torque peak from the engine.

Matador,
Transmission slip is calculated based on a relationship between transmission input shaft speed and transmission output shaft speed. Prior to the torque converter locking, transmission slip is difficult to detect because the nature of an unlocked converter is contributing to a speed discrepancy. After the TCC is locked, slippage may be present in the TCC or in any of the internal clutches in the trans, and any discrepancy in the input speed and output speed (allowing for gear ratios) can be considered a percentage of slippage.
 

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PeterT said:
Burner,
Granted, the testing that we do may not be “real world”, but it is clearly worst-case scenario. It allows us to know beyond a shadow of a doubt what the performance of the vehicle will be under the worst of conditions. By testing in this manner we find all the weak spots, slippage points, etc., and we know what is safe for the long term as opposed to a quick flash snapshot. We manipulate the trans to be able to achieve readings lower in the RPM band. This makes testing on an automatic similar to the type of results you might get with a manual without the hassle of slipping the manual clutch. If we didn’t manipulate the trans, we would probably never see the torque peak from the engine.

I understand that you "hold" the tranny down (holding in higher gear) so that you can find TQ and HP readings. However, I do not understand a hassle of slipping the clutch. Would it not be prevalent to test the 6-gun with a manual? Are you saying that the Allison automatic will hold more TQ/HP, in lower RPMs, locked in 4th than a manual trans in 4th? Torque peak by locking in gear? I don't see how manipulating the trans with the Allison tool would help attain Torque peak? I thought that TQ peak was attained by RPM, the 5252 division thing? Perhaps I'm not reading this correctly. I would think that Banks is reading how much the Allison can take @ low RPM and how much the engine can deliver @ low RPM and then optimizing the power curve so that the trans will live.


I'll guess that's what you're trying to say and what you fellas are doing. So, does that mean if youa have a trans-go, ATS or SunCoast upgrade or replacement that the 6-gun will not follow? Is the 6-Gun regulated to deliver "only" the power that a stock trans will hold? Maybe the 6-gun produces or gives the engine only what a stock trans will hold until the converter is locked and then the Allison programs take over, which allows full power provided the input and output readings are equal in relationship to the gear. All this without mentioning the stinger.....just the 6-Gun.


Thank you for all of your input Peter.






Burner--------------->
 

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Discussion Starter #13
Burner,
Think of it this way. When we test on an engine dyno, we are measuring horsepower and torque at the flywheel of the engine. We are able to paint the cleanest possible curves that the engine produces without the added effects of slippage in the trans, traction at the rear wheels, or eny other effects the vehicle may have on engine performance. We can learn a lot about the capabilities of the engine itself on an engine dyno, but there is a downside. The engine dyno does not show us what influence the transmission and the rest of the vehicle will have on things.

When we go on the chassis dyno, we do a number of things. The power and torque curves that you see us publish are the result of simulating as direct a relationship between the flywheel and the rear wheels of the vehicle as possible. That means that we want to have the transmission in its direct gear (1:1 relationship, no gear reduction or overdrive), and when a torque converter is involved, we lock it in order to eliminate any influence it would have on power readings. This is the closest that we can get to having measurements that are similar to the engine dyno, but that include the vehicle dynamics as well. When we are able to “hold” the TCC locked and the transmission in its direct gear, we can take measurements throughout the operating range of the engine. These measurements are always taken at wide open throttle (WOT). In the case of the Duramax, the stock torque curve is very flat from 2800 rpm clear down to 1800. With the Six-Gun and Speed Loader, the torque continues to rise as rpm drops from about 625 lb-ft at 2800 clear up to almost 850 lb-ft at 1800. Without locking the trans, we would never see those numbers below about 2200 if we allowed the trans to naturally backshift, and the manual transmission clutch starts to slip with high torque, so it is not a good candidate for this type of testing. Manipulating the trans has nothing to do with actually producing the numbers, it only allows us to run the engine in that range so that we can see what is there.

But that is not all that we do on the chassis dyno. We also will do acceleration runs without manipulating the transmission to ensure that we do not cause check engine lights, cause undesirable shifts, etc. And when we are done on the dyno, we take the vehicle out on the road to ensure that drivability is good and check things like fuel economy.

Under most conditions, the use of a Six-Gun with a stock Allison transmission will not result in any slippag
 

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Peter,


I got an e-mail this afternoon directly from Banks News. I thought "could this be the racebox info?" Low and behold, when I opened it up, it was just about the Six-Gun. Damn, I got excited there for a sec.....
 

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Scotty Seelen said:
Peter,


I got an e-mail this afternoon directly from Banks News. I thought "could this be the racebox info?" Low and behold, when I opened it up, it was just about the Six-Gun. Damn, I got excited there for a sec.....

Ditto
 

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Burner the only way any performance mod would be noticed fully is with a manual trans. The big tq gains low in the rpm range wouldn't be used in an auto at all in the real world because either the tranny would downshift or the convertor would be unlocked allowing the rpm's to be above that level. As for Peter's statement of the stock manual clutch not holding 70 or more additional hp shows again how out of touch with reality banks information is. All stock clutches will hold much more than that and even after much abuse will hold most company's 70 hp upgrades so I am positive they will hold considerably more than 70 banks hp in most any condition.


P.S. I think this statement by Peter sums it up. "I don’t think we have found the maximum capability of the Allison trans yet" So you can't overpower an allison but you stock 6 speed clutch slips, right.
 
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