EarthRoamer installs TripleLok

[Cummins Corvette]

If I do the "curb test", with my DTT stuff, it will either go up the curb, or make some tire smoke when boost kicks in. That is not a problem. The problem is that it will generate a lot of heat when I do that, and it takes a couple of seconds for boost to kick in.

 

[GLASMITHS]

CHEBBY WID DA CUMMINS!!

About all I can say is you may be in line for a new truck!



With plenty valvesOo.

 

[D. Showan]

I did the curb test with my Goerend TC on the way to work this morning at a McDonalds. I went thru the drive thru, pulled over and got squared up to the curb, eased on the throttle and went right up. When coming back down the curb I let it come down to fast and my orange juice tipped and went flying all over my passenger seat, floor etc. and had to spend the next 10 minutes cleaning it up. I was real happy for about 5 seconds. Don't have any rpm or curb height numbers yet, I'll try another curb later

 

[Fred Swanson]

Originaly posted by EarthRoamer:

I may be wrong, but it seems to me that even with good torque multiplication, a stator could have too low of a stall speed. If the Cummins can't develop enough RPM to get fuel and boost pressure up and begin developing HP, the truck wouldn't move.



Bill, this is true to a point. That's why there are multiple versions of converters being developed. Eveyone has their own idea of what works.



I can tell you from firsthand experience with all three DTT converters, they can easily pop up on a curb without having to work it too hard. One of the tasks at hand from a transmission technicians perspective is matching the converter to the truck and its intended use and HP and on and on.



Where I live, my property is flood irrigated. The berm from my grass to the rock driveway is about 12 inches high, and I can pull up to it, and idle right up, without having to touch the throttle.



With DTT's 89% TC, it works best for guys in altitude and towing. The 91% works good here to ,along with higher HP trucks. Now with the 93%, even better for more HP but not towing.



I wouldn't recomend the 93% to someone who tows, just like I wouldn't recommend the 89% to someone with 500 HP.



Take this same TC and put it behind a gasser, and it has problems, because it doesn't produce the torque at idle the Cummins does. That's why the tighter TC's can work behind them.



In my previous post, I mentioned pulling 18,000 lb from Texas to Arizona. Technically I dropped one trailer in New Mexico, so I pulled this load 750 miles, and the remaining 14,000 lb to Arizona. This was done with a 93% TC, DD3's, HX-40 and on and on. I wouldn't recommend this setup for someone doing it all of the time, but the Cummins had no problem getting the truck moving. I spent plenty of time driving in slow traffic, stoplight to stoplight in small towns along the way, and was very impressed with how easily it got off the line.



This motor makes plenty of power to get moving easily, even under load. You have to also consider gear ratio and tire size.



EarthRoamer:

What size tire and gear ratio are you running? Last time I saw a reference in a mag, you had switched from 37's like a Hummer to Michelin military 37,38's and running 4. 10's. Please correct me if I am wrong.

 

[Cummins Corvette]

Originally posted by Strick-9

EarthRoamer,



I'd like to challenge your last post.





With your engineering degree, I'm sure you'll understand this.



When a TC clutch unlocks, it allows the engine to gain rpm. Under MOST driving conditions, more HP is available at a higher rpm.



When a TC clutch is unlocked, some energy (HP) is lost due to heat. But more HP is available at the higher RPM. So it depends on how tight the fluid coupling is and what RPM the engine is operating at as to whether more HP will get to the ground by unlocking a converter.



There are people all over the country pulling trailers with a locked TC clutch and being bogged down. They simply unlock the converter and finish the hill, in the SAME gear because they are putting MORE hp down unlocked.





-Chris

No flaming, but I am going to disagree with you here. Torque multiplication only really happens at very low turbine speeds (i. e. when stopped and just starting to move and there is a difference of more than ~600 or so rpm between the engine and the input shaft). When you are driving at 45+ mph, the slipping tc is turning the extra hp available at higher rpm directly into heat, and is creating a very inefficient situation. If you want to efficiently finish the hill, just downshift.



So when you unlock the converter while towing up hill, you are putting less power to the ground because the amount of torque being produced by the engine is less at the higher rpm. The only reason you are able to finish the hill is because the slipping tc is letting the engine stay up in the power band longer, but you will have to down shift if you are to continue up the grade (if you aren't near the top). Anyone can try this for a test: tow a heavy trailer up a long steep hill. Parleys canyon is an ideal example. Put the transmission in third and unlock the tc. Now proceed up the hill. Take note of your transmission temp, and the speed you are going up the hill. Now do it again with the tc locked in the same gear. You will go up the hill faster, and with a lot less heat generated in the transmission (tc).



Now Chris is saying that you can just unlock the tc to finish the hill (i. e. already near the top). I don't think this would be any different than slipping the clutch in a manual. Sure, you finished the hill in the same gear, but you made the clutch very hot, and you continued to slow down. A tc has two different modes of internal flow. The first is where torque multiplication occurs: this is called vortex flow. Once you get moving, and the turbine (input shaft) and pump (engine) rpm are within 30% of each other (i. e. engine going 30% faster than the input shaft), the converter goes into rotary flow. In rotary flow the energy (rpm) difference between input and output of the tc is lost in heat. There is no torque multiplication in rotary flow.



So no, unless you are moving VERY slow, you are ALWAYS putting less hp to the ground with the tc unlocked.

 

[Cummins Corvette]

Originally posted by D. Showan

I think some of you are looking for some magic.



If you have a torque converter with a lower stall speed you MUST have less torque multiplcation. That is why the stall speed is lower,the torque multiplication is lower and that is why the engine wont rev as high at a stop.

I don't think you are entirely right. Yes, a stator that is milled incorrectly will lower stall at the same time it reduces torque multiplication. E-mail Bill K. and ask him what his thoughts are on your statement.



Lowering stall and reducing torque multiplication don't have to both happen at the same time. The design of the stator is what determines how each of these are effected. An old BD milled stator is a perfect example of stall being lowered at the expense of torque multiplication. Look at a stator that has been milled in the old way (like an old BD), then compare that to the way ATS machines their stators, then look at a stator from a DTT transmission. You will see that the ATS stator looks very similar to the DTT, and the old BD just has half of the stator cut off. THIS is what reduces torque multiplication; it is not a result of lowering stall. It is a side affect of lowering stall incorrectly.



Now there is another angle to this. If the stall is so low that the turbo cannot spool at all, then the engine isn't feeding as much torque into the converter to begin with, then you have what could appear to be a reduction in torque multiplication.



Just remember that the two DO NOT have to BOTH happen at the same time.

 

[Cummins Corvette]

Originally posted by rrausch

I'm almost sorry I asked the "curb crawl" and "boat ramp" questions, but it was the best way I could think of to try to discern the "off the line" difference between DTT & ATS & BD & Goerend.



I mean from some of the posts I have read DTT's have been reported to be a little smoky with low rpm's "off the line". Please correct me if I am wrong. To my way of thinking that might not be so good for me because I drive city stop and go 90% of the time.



They all seem to have good systems. But if DTT crates more heat than ATS that is information which should be known. Conversely if DTT gets more power to the ground than BD, then that is something which should be known also. Or if Goerend is a lot cheaper than any of the others, then there is information too, which should be known.



Which one is best for me? That is the question I am asking.



Personally I also think all the guys who bought DTT's are now worried that ATS has a better system.

I agree that everyone should know all of the facts before spending their money. For someone who spends a lot of time in traffic and wants a DTT transmission, I would recommend the 89%. The more a tc "grabs" with a low stall, the more heat it will generate at a stop in drive. This is one of the reasons I am switching to ATS. I want everything. I want my transmission to be cool in traffic, I want it to transfer just as much power as a manual, I want a lot less turbo lag, I want good torque multiplication, I don't want it to stall anymore, and I want it to last forever. ATS might not be able to make it last forever, but they can take care of all of the other items. If I can think of anything else, I will want that too.



The main reason I am switching is because the DTT converter stall is to low, and the top end is to loose. More detail can be found in my previous post, but lockup is ABSOLUTELY NECESSARY for efficient high rpm (greater than ~1500) power transfer. The more power your engine makes, the bigger difference lockup will make at high rpm. Any slippage is only creating heat and putting your engine at a rpm where it makes less torque (for the most part). At speed your tc is only transferring torque, not horse power. That is to say that at speeds greater than about 20 mph, torque in = torque out. If you unlock the tc on the freeway for example, your engine might be operating at point which it makes more hp, but less torque. Horsepower is a product of rpm and torque, but you loose the rpm part as heat, and are left with the torque ONLY.



As for the ATS being BETTER than the DTT or the other way around, that is like asking which is better: a Camero, or a Mustang. It is a matter of opinion, and they each have aspects that are superior to the other's. I was going to say that DTT has a lower stall, but ATS can make you a stator for whatever stall speed you want (while still maintaining torque multiplication). You aren't limited to three (or whatever) choices. For those who want what I do from their transmission, I think they will be happier with the ATS.



The people who have a DTT transmission do not need to think they got the shaft because they (we) didn't. My transmission is very good, but any man made product can be improved upon.

 

[D. Showan]

First I would like to appoligize to EarthRoamer for any part I played in lowering the tone of this discussion. It was kept pretty much on track until the last dozen or so posts. This thread started out as a discussion of your story in using ATS's triple lock, look where we are now. While I find this discussion very interesting I don't feel right continuing it here. This thread was started by a honorable and knowledgable man talking about a very good product from a very good company.



Cummins Corvette, While I agree with most of what you said I do have a few differences of opinion, however, I am open to have my mind changed.



Unless EarthRoamer chimes in again and says let the discission continue, I'm going to reserve other thoughts I have for another time and thread.

 

[GLASMITHS]

Mr CORVETTE

You are implying that you are smarter than Bill K. and that the DTT Smart Controller is dumb. Since the Smart controller is the DTT t/c Saver with many other features.



Since you own DTT equipment and know how everything works why are you saying all this? Strick9 was right.



I do not know much about trannys period. Your last posts lost me early on, but thanks for the education. I didn't know it worked like that.



I'm sorry you don't agree, but unlocking the t/c on the hill gives you more power and lower egt. Maybe the temps go up some, but not into the danger zone (250+). So what is the big deal with lock-up. It's good for sailing down the interstate, and if you have the HP it would be like a stick on the strip.

 

[Cummins Corvette]

Originally posted by D. Showan

First I would like to appoligize to EarthRoamer for any part I played in lowering the tone of this discussion. It was kept pretty much on track until the last dozen or so posts.



Cummins Corvette, While I agree with most of what you said I do have a few differences of opinion, however, I am open to have my mind changed.

If I have in ANY WAY offended you, I sincerly appologize.

I hope Bill (earthroamer) stays in this. This is a good thread.

The above posts by me come from information from Clint Cannon, and my own personal experience.



So what do you want to know? I will do my best to answer your questions.

Originally posted by GLASMITHS

You are implying that you are smarter than Bill K. and that the DTT Smart Controller is dumb. Since the Smart controller is the DTT t/c Saver with many other features.

Now hold on there please. I don't remember saying anytning about the smart controller; I don't have one of those. I said that I don't like the tc saver, I did not say that it is stupid. I believe it does its job of making the transmission last longer very well. Perhaps I should have said I don't like fluid coupling, no matter how efficient, for high speeds.



I don't remember saying that I am by any means smarter than Bill K. However, I do have a difference of opinion. That is all though.

Originally posted by GLASMITHS





Since you own DTT equipment and know how everything works why are you saying all this? Strick9 was right.

Right about what?

 

[GLASMITHS]

More HP is available at higher rpm. It depends on how tight the fluid coupling is. That is what determines the amount of heat.

IMHO

 

[D. Showan]

Okay, I'll post one more time.

Cummins Corvette, You have not offended me in the least. Your statements directed at me have been very professional and in a positive manner. I don't really have questions for you but I would like to share more ideas I have with you and try to make you see things a little differently (the way I do).



Maybe I'm giving to much ownership to EarthRoamer for starting this thread but he has "left the building " so to speak and that bothers me. A little while ago I started a thread to tell people how happy I was with the TC and VB mods I received from Dave Goerend. I would have been really disgusted if it had turned into a discussion about Goerend vs. DTT or someone else. It didn't and I want to give everyone else the same courtesy.



If EarthRoamer is gone, I need to shut up. Thats just the way I feel. I am looking forward to continuing with this at a later time. By for now.

 

[GLASMITHS]

DON'T LEAVE YET

D. SHOWMAN: You can't leave, we got to teach Cummins Corvette and EarthRoamer how to jump curbs.



Somebody posted about DTT smoking too much

If you miss-understood my post, I ment to say my tires were smoking, IMHO, a transmission does not produce smoke

 

[fest3er]

Originally posted by Cummins Corvette ... At speed your tc is only transferring torque, not horse power. That is to say that at speeds greater than about 20 mph, torque in = torque out.

If I understand the mechanics of a torque converter, it transfers HP. Power in must equal power out. And since there are two constants at any point (HP is one, RPM is the other), then it *must* be torque that changes between the engine and trans.



Consider that the engine is turning at 2500 RPM and the trans is turning at 2400 RPM. Suppose that your engine puts out 215HP at 2500 RPM. This would be about 451 lb-ft of torque. 200*5252/2500.



Since the power across the TC must be constant, the trans must be seeing about 470 lb-ft of torque. 200*5252/2400.



If the engine was turning at 2500 RPM and the trans at 1600 RPM, the trans would be getting 705 lb-ft of torque.



These figures ignore heat loss, which would show as dscreased HP at the trans.



This is the origin of 'torque multiplication'.



And because power is lost to heat, a TC working unlocked is less efficient than one working locked. However, that is not to say that there is *never* no mechanical advantage to running unlocked at speed. Consider the 705 lb-ft trans torque at 1600 RPM trans, 2500 RPM engine. The 215 HP motor might be putting out 420 lb-ft torque at that speed, which is about 127 HP. You'd have to compute the heat loss to determine the HP loss. Maybe you'd still have an advantage unlocked. Maybe not. Questions best left for a thermodynamics expert!



Fest3er

 

[Cummins Corvette]

Originally posted by GLASMITHS

More HP is available at higher rpm. It depends on how tight the fluid coupling is. That is what determines the amount of heat.

IMHO

You are right about more hp being available at higher rpm (up to 2500 in my case). But you need to remember that when you unlock the tc, you loose the hp gained by the increase in rpm to heat. All of it. When you are moving fast enough to need lockup, the converter has no torque multiplication. This is why torque in = torque out at high speed.



Here is the math. All of the following numbers are only for this example and don't necessarily come from any one truck. Lets say you're cruising down the road at 1800 rpm, and the engine makes 400 ft/lbs of torque at that rpm at full throttle. Now you unlock the tc, and remain at the same speed. Now the engine is at 2300 rpm, and only makes 380 ft/lbs of torque at that rpm. Before, with the tc locked, you had 400 ft/lbs going into the transmission. Now, with the tc unlocked and not doing any torque multiplication, you have 380 ft/lbs going into the transmission. Where did the power from the other 20 ft/lbs and 500 rpm go? It is being transformed into heat.

 

[Cummins Corvette]

Originally posted by fest3er





Since the power across the TC must be constant, the trans must be seeing about 470 lb-ft of torque. 200*5252/2400.



If the engine was turning at 2500 RPM and the trans at 1600 RPM, the trans would be getting 705 lb-ft of torque.



These figures ignore heat loss, which would show as dscreased HP at the trans.



This is the origin of 'torque multiplication'.

Fest3er

There is one thing wrong with that logic. There IS NO torque multiplication at speed. This has been covered in one of my previous posts, but that's ok, I can re-type it.



When you are on the freeway, unlocked, the converter is in rotary flow mode. When in this mode, it cannot multiply torque. Torque multiplication happens when the tc is in vortex flow, when you are starting out from a dead stop, and there is a great difference in engine speed vs. transmission input speed. If the engine is at 2500 rpm, making 450 ft/lbs of torque, and the trans is at 2000 rpm, it is getting 450 ft/lbs of torque because at this point, the tc is in rotary flow. No torque multiplication is happening, it is only making heat.

 

[fest3er]

Originally posted by Cummins Corvette ... If the engine is at 2500 rpm, making 450 ft/lbs of torque, and the trans is at 2000 rpm, it is getting 450 ft/lbs of torque because at this point, the tc is in rotary flow. No torque multiplication is happening, it is only making heat.

Ok. So you are saying that 43 HP (or about 32KW) is lost as heat? That's gotta *really* heat up the trans oil!



BTW, I'm assuming 760W/HP.



Fest3er

 

[JIM S.]

trying to remember.. could be wrong

and the impression I got was that if your pulling up a hill with a big load and you dont have 400 or 600 HP and you just cant quite top the hill lugging in LOCKED OVERDRIVE and you dont want to shift to LOCKED DRIVE and redline it... ... ... ... its handy to unlock the TC and get a few RPMs to get you over the top. now I realize that with the gearing we have you cant really go from lugging to redline... we have a bit more range than that. But that is what I got when I read the first post mentioning this.

Jim

PS... I got a chance to use a G-Tech and the best was 260 hp. :{ BUT I love the slush box... I can add in %20-%30 and get a better number to tell ppl, it should be somwere between 310 and 340 HP

 

[Todd T]

this has been yet another, good transmission thread IMO



now that i am back in the market for an auto. my interest in this in way up there. lets not forget Mr. Mcbride (stack'd-n-jack'd), Eric just signed up for a new ATS transmission and he is already running in the low 13's as in near 13 flat. he tells us he plans to be in the 12's this season. I will be watching him this year, with toothpicks proping my eyes open



at this point i can say i'm right in the middle of the fence. first of all, my wife will be taking the Ramburban when its done. i dont need the sidewalls of the tires wrinkling with shifts, having to train my son to be a co-pilot in charge of instrumentation and i dont plan to go over 450HP with it. nor do we tow often. I want my power to the ground ASAP and better MPG's.



at this piont i"m thinking ATS converter and controller(couldnt find the price for DTT's). DTT trans kit and VB. that leaves me with $800 dollars left to spend with Piers. right now i have $725 worth of stuff on my list from him



all i can say is stay tuned and lets hope theres a price war in the near future



BTW Bill, i enjoy your articles more than once each time i get a new issue

 

[StakeMan]

I am glad I got the 4. 10's. There isn't as much of an RPM drop between gears.