ATS or DTT converter?

[ChadHarlan]

So what kind of torque multipacation does a DTT stator make. I just want to know why thier fliud coupling is better than some.

 

[MCummings]

It's at 1,200RPM.



At WOT it shifts great, but anything less,,, and it's manual downshifting. I've allready figured this problem out,,, and it's something I've been wanting for a LONG Time, but I don't have enough $ to do everything I want, so I'm stuck with my hand on the shifter for now.



I can go ahead and get on it real hard, and it will shift later, but using 75% of 530HP, disrupts the public peace.



Merrick

 

[banshee]

Merrick,



I can tell you this:



I got my ATS transmission after Eric had his swapped in.



When I bought my transmission it was in the era before billet shafts were being produced, so all I could get was a cryoed input shaft... that's it! No billet input, no billet output, no emjay controller, and no 1st gear lockup. So, yes, I think you did get a race transmission that was available with the technology of the time. Is it cutting edge today? No. But that's what you get when time moves on. As for the converter efficiency, it sounds like yours may be a little looser than the norm. My truck would make 15 psi at around 1700 rpms, and both of dad's trucks are the same way. To say that your transmission is the "Standard ATS Stage 4" is a bit of a stretch IMO.

 

[MCummings]

banshee,



I thought this transmission was fairly new when I bought the truck, or, that's how I was led to believe. I thought it wasn't more than a few months old.



It wasn't in too bad shape when I tore it down, although 3rd gear was a bit dark, (heat spots).



The transmission you put in the truck is the same transmission that was in it when sold?



Merrick

 

[banshee]

Merrick,



I have no idea what was in the truck when you got it. All I know is that originally, when the swap was first done, it was in the time before billet shafts, etc. I got all I could for the time, and it didn't include anything billet... . just cryo treated.



As for my transmission, yes, I sold the same exact transmission I bought/built when I first put the ATS in my truck. The only change from the original purchase was a new input shaft hub... I stripped the splines out of the original hub on a 1-2 shift while street racing. It lasted about a year behind my 450-500hp... not too bad for a stock hub. While the shaft was being swapped the clutches were inspected and they were good to go. The seals were replaced for good measure, but besides the seals and that hub all was the same with no probs. It's still running today in a buddy's truck that putting down ~350hp.



John

 

[c-hawk]

Originally posted by Edward

Merrick

You are right lets do the calculations. Sight rules prohibit me from mentioning company names but there is a company down on the sunny coast of Florida that has done their calculations on which theory they believe is superior and they concluded that three lock up discs are better than one. There is another company run by brothers in Iowa, that have also done their calculations and concluded that the theory behind three lock-up discs better fits the needs of their customers than one lock-up disc. There is yet another company in Germany who has engineering capabilities that are world renown and they have rejected the theory of super tight fluid coupling to that of locking up with three discs. The last company’s location is in Wheetridge Colorado and they have been ridiculed for concluding that three lock-up discs are much better than one. I don't think that the companies, which reside at the locations listed above, would purposefully reject the superior method in favor of providing their customers second best. I am not about to say that any of the aftermarket transmissions are junk because they are all way better than stock. But I can sit down and calculate that 3 of the most commonly mentioned transmission companies listed on this sight have chosen the theory of three lock-up discs over one lock-up disc. I can also recognize that the company in Germany is in agreement with those three companies listed above due to the fact that they are utilizing the same theory in their new transmission. When I sit down and do the calculations it comes out to, 4 out of 5 in favor of three lock-up discs.



Edward

More does not always equal better. Ford and GM, among others, think 8 cylinder diesels in a V are better than 6 in an I. So tell us all how the Powerstroke and Duramax are without question better than a Cummins and then I'll be convinced. Not apples to apples, but using your logic the V8 diesels must be better in a pickup truck.

Originally posted by Edward

Chris actually you can do what Maddog is doing with a Dodge transmission. Here is sight where you can get the lock-up controller and a quote from the sight. I would not recommend this product unless you have a multi disc lock-up converter.

www.emjay-eng.com/loun.html





Edward

Hmm, learn something new everyday. I hadn't heard anyone mention this device before. So maybe it is possible to get lockup with this thing at lower speeds and gears.



But please answer me why one would need a multi-disc converter to use it. This device will be very hard on any transmission, no question about it. But if a converter can hold lockup in 3rd or O/D at WOT without slipping, what makes you think it would slip in first or second? Seems to me the engine makes the same power no matter what gear it's in, but the transmission has a mechanical advantage, as you go to a lower gear. Is this right?



Look at a 6spd truck for example. If you were pulling a load in 6th and the clutch was slipping, often times you could downshift and the clutch would be able to hold in a lower gear.



So if you could explain to me why a converter that can hold WOT in O/D wouldn't hold in first i'd appreciate it.



Thanks,

Chris

 

[c-hawk]

Originally posted by Matt400

Ok, can't get all that much heat going at a stop... but with a tight converter pulling the engine R's down it stands to reason the engine controls will up the fuel to bring idle speed back in spec then you have one fighting the other.

Matt, I honestly don't have an answer for how much extra fuel a truck with a tight converter will burn stopped in gear vs. one with a looser converter. I can't imagine it being a significant amount though, unless your sitting for very extended periods of time. In which case, put it in neutral or park. Seems to me that the efficiency of a tighter converter when moving will more than make up for the extra fuel it could burn while stopped. (I'm not even sure that it will require extra fuel stopped, but it seems logical to me. ) If your worried about them "fighting" each other, have no fear. The brakes are definitely strong enough to hold back a DTT'd truck at idle. Does require a little more pressure on the brake pedal than a stocker though.

Originally posted by Matt400



For a daily driver that condition might be annoying- I can't say cuz I still have a stocker. I have been watching my tach more often and I can say that the stock converter keeps the engine in the meat of the torque range from off idle to just over 1/2 throttle. Past that and the R's get up higher than they probably should for the Cummins while out of lock up.



I still haven't heard "why" a trip-loc is any better other than 3 must be better and some other companies are using it.

If a single disc won't slip for my power levels its hard to justify the added expense of the 3 disc however I am a little concerned that the tight fluid coupling while it is awesome might give me less than desirable drivability from 0 to 5 MPH, you know parking lot maneuvers not stomping the pedal to the floor.

Each person has to decide for themselves what they like and don't like. That's the beauty of having so many choices. While i've found what i like, i'm very glad there are other options out there for others that don't think the way i do. Keeps it interesting.



I know your looking for a 48re, but may i suggest you put a call in to bill and ask him how the converters compare to the ones he's using in 47re's. If they're similar, which i'd guess they are, you can probably find someone close to you with a 2nd gen DTT to try out. See first hand if your concerns about low speed handling are worth having. That's probably the only way you'll be 100%confident that your going to get what you want, if you try before you buy.



Chris

 

[MCummings]

If a DTT is 91% and the ATS is,, for conversation sake 87%... .



You would be using 4% more fuel at idle with a DTT, and while accelerating (Both unlocked) you would be using 4% more fuel with an ATS.



Say, you've governed your truck at 250HP.

A DTT in Direct, Unlocked, would put down 227. 5HP

A ATS in Direct, Unlocked, would put down 217. 5HP



(This didn't take in account any HP to drive the pump, or bearings in the transmission. )



So know,, to accelerate equally unlocked, the ATS equipped truck would have to put out 4% more power than a DTT truck.

That means, An ATS, to accelerate with, or to keep moving a load with DTT, would have to make 260HP.



This also translates to the dragstrip... .



Lets take 10HP per pound of Boost.....



Just for pokes and giggles, I don't want to work gear reductions, or axle ratios, so lets say 3rd gear, measured at the driveshaft.



A DTT truck Builds 15PSI boost. That motor is making 150HP.

With 91% Efficiency, the transmission is applying 227. 5HP to the Driveshaft.

A ATS truck builds 15PSI boost. Same motor, making 150HP

With 87% Efficiency, the transmission is applying 217. 5HP to the driveshaft.



That means, during the time your truck is accelerating to lock up,, your DTT transmission is putting 10 more HP to the ground, than the ATS truck.



The difference in HP will become greater as HP is increased.



A 600HP Truck will put down 546HP with a DTT

A 600HP Truck will put down 522HP with a ATS



That's 24HP Difference.



1/4 mile experts,,,,

What will 24 Extra HP do to a 7,000 Lb truck in the 60'? Considering you can launch, and hook up at full power.



So, Now, not only are you transfering a 4% difference in power,,,, both converters also hold 100% of power in Lockup.



Merrick



I tried to make this as nuetral as possible.

I didn't even bring in different compnents that are changed to help apply more pressure to the clutches, at the same pump output pressure.

 

[Jim Fulmer]

It wasn't in too bad shape when I tore it down, although 3rd gear was a bit dark, (heat spots).



That My friend is nothing but Direct clutch slippage... ... that's the second set of clutches for that transmission.





Banshee, I know what you mean about the hub stripping off..... did that one too before going to Billet, don't know how it lasted so long.



Jim

 

[ChadHarlan]

SO does any one know what rate of torque multipacation the DTT stator makes? I am reading about efficency, but not the exact rate. And the multipacation of torque is what gets you moving correct?

 

[Edward]

Originally posted by c-hawk

More does not always equal better.

True but if I had to put money on which approach was better I would have to go with the odds. More companies are producing multi disc torque converters than there are companies relying on increased fluid coupling and a single lock-up disc. Secondly all of the predictions on how multi disc torque converters would fail have turned out to be groundless. This is only my opinion but when I want information about a product I want it from someone who can get it right.

But please answer me why one would need a multi-disc converter to use it. This device will be very hard on any transmission, no question about it. But if a converter can hold lockup in 3rd or O/D at WOT without slipping, what makes you think it would slip in first or second?... So if you could explain to me why a converter that can hold WOT in O/D wouldn't hold in first i'd appreciate it.

Chris

First of all it’s for drag racing and by definition drag racing is hard on your transmission. Just like standing on the brake and giving the engine fuel to build boost is hard on the transmission. However the triple disc torque converter has three times the holding power of a single disc TC given the same apply pressures.



Edward

 

[Sled Puller]

ATS 40 32. 00%

DTT 69 55. 20%

Neither and why? 16 12. 80%





Funny, I don't even see on this poll that he wants your DTT or ATS opinions.

However, on the NEITHER catagory, it does ask, WHY?





Well, I'm number 16 on neither, but I'll save Steve the trouble to edit my post, but let me say this,



.

 

[How'dHeDoThat]

Good One Sled,











James

 

[c-hawk]

Originally posted by Edward

True but if I had to put money on which approach was better I would have to go with the odds. More companies are producing multi disc torque converters than there are companies relying on increased fluid coupling and a single lock-up disc. Secondly all of the predictions on how multi disc torque converters would fail have turned out to be groundless. This is only my opinion but when I want information about a product I want it from someone who can get it right.

Edward, you did put money on it when you bought your transmission. But to me, your logic just doesn't make sense. If more companies doing something makes that a better way, then look at my comparison above. Why then don't you believe V8 diesels are better in a pickup? What's the difference? Go with the odds right? It's usually more complicated than that.

Originally posted by Edward

Chris

First of all it’s for drag racing and by definition drag racing is hard on your transmission. Just like standing on the brake and giving the engine fuel to build boost is hard on the transmission. However the triple disc torque converter has three times the holding power of a single disc TC given the same apply pressures.



Edward

1. Why would a converter that can hold lockup in O/D slip in a lower gear? Doesn't make sense. If it holds in O/D it's just going to hold, IMO.



2. If this wasn't a converter thread, I'd be curious to know why you think the converters are the weak link in our transmissions. I believe any of the converter's out there are probably much stronger than 3rd gear, at least in the 47re. Maybe that's changed in the newer trucks. Look at Merrick's post for evidence of that. He's slipping 3rd from the sound of it.



Chris

 

[MCummings]

Nobody cares to combat my post?



Chris,, I've preached a bunch, that 3rd gear is the weakest link in the transmission.



Oh, Goodness,, Your Converter will hold 2,000Lbs of Torque! That's Awesome.

How's third gear doing? It's slippied to smithereens, because it let go at at 1,500 Lbs.



Where are the weak links in these trannies?



Valve Body, Internal leaks, and an inefficient converter. The converter isn't really the one that goes out,, usually, it's the clutches slipping, then junk gets in the converter, and ruins it.



I know a guy pumping over 400RWHP for the last 25,000 miles on only a modified VB, and raised pressure.



Merrick

 

[ChadHarlan]

Convertors are a big failure in a lot of time. Glazed cluthes or sometimes it is metal to metal. It is a half and half failure of tranys and convertors.

 

[Edward]

Originally posted by c-hawk



1. Why would a converter that can hold lockup in O/D slip in a lower gear? Doesn't make sense. If it holds in O/D it's just going to hold, IMO.

Chris

Chris

I posted the reason why in my last post but Steve evidently felt I was commenting on a brand of transmission that I do not own and he edited it out. Since you have asked the same question again I will try to phrase it in such a way that I will lead you to the answer without commenting about a product I do not own.

I have read quite a few posts on torque converters about RPM being directly related to holding power. I think that is where you need to look for your answer. I believe if I were to elaborate any more that this post would also be subjected to the editing knife of the moderator.



Edward

 

[Matt400]

I believe these are your words Steve:

The only solution I can come up with to stop this is to institute a rule that when it comes to automatic transmissions if a post is started about ATS trannies ONLY those with ATS trannies or stock can post to it. If a post is started about DTT trannies then ONLY those with DTT trannies or stock can post to it



Over moderation will only stifle TDR growth and risks sending members to other sites.

 

[Steve St.Laurent]

Right after that is this:

If a post is asking a general transmission question you can post how your transmission modification works - but DON'T discuss the other side AT ALL. Posts WILL be deleted with no notice that do not meet this standard.

Believe me auto transmission posts have been more work on the moderators than all other heated topics combined. The last thing we want to do is over moderate. We came to this policy after several years of trying other methods. It has been very popular members of the site. I regularly get emails thanking us for the policy and people reporting posts that do not meet the policy. Basically it just says talk about the aftermarket transmission you own and not the others. IMO, that allows for the most accurate information to be out there - after all, if you don't own what you are discussing how do you know about it? The policy was put into place around the time you signed up Matt, so you probably aren't familiar with all the problems we've had in the past.



BTW, posting things such as "a certain company in Canada", or "a certain company in Colorado" is an attempt to get around the guidlines and will be dealt with the same.

 

[John_P]

Matt 400:



You were asking earlier about "how the ATS TripleLok"

is "different?" One big difference is that the ATS TC

has 119 square inches of lock-up clutch surface area

versus 34 square inches for the "stock" Dodge Converter.

To me, that is a big difference! When you go from a "stock"

unit or even a "modified" TC with the "single" disc and you

drive the truck with the ATS TC the, "feel" in the transmission

as the vehicle shifts is much, much different! You notice

it immediately!



---------------

Merrick:



You said earlier: "Nobody cares to combat my post?"



It sounds to me after reading and discussing this subject

with you that you are just terribly unhappy with the ATS

transmission in the truck you bought from Eric! As "banshee"

said, the truck had the "swap" done (5 speed to ATS auto)

and like "banshee" I wouldn't be able to tell you what was

in it either or if anyone besides ATS has worked on that unit!!!



IMO, the "technology" has moved forward since we (myself, Eric

banshee, and others) have bought ours. Personally, I thinkthings are getting better all the time and that helps all of us with all of the manafacturers!!





What I would recommend to you is that if you are not happy

with the ATS transmission then take it out and go to another

builder like DTT!! BTW,... ... no offense to you or anything,... .

but as you say "just my . 02cents!" Good luck with your

decision!



------------

John_P