Engine/Transmission (1994 - 1998) Auto Trans and Triple Disc Converters

[DavidTD]

These threads are fun. :-laf

 

[I-6DZL]

David do you care to chime in here??? I'd love to hear your side of an automatic trans!!!!!



Can never learn too much.



Curtis

 

[Mark_Kendrick]

These threads are fun. :-laf



David Dunbar

Diesel Performance Motorsports.com



1998 2500 12v 4x4 Garmon Built Twin Turbo

Sun Coast Pro Loc

I wonder where he stands on the multi disc debate

 

[mjoppie]

ok, i have a question about the singke and mulitdisc converters. i personaly went with a single disc graphite lined converter for my truck that wont be over 350hp for a long time. what rates them different? like i was told that a single disc converter is alright to run with 600hp but just drag racing and driving where theres no continued stress on the transmission. like dunrite advertises under 450 and 20,000lbs is alright to run a single. i read about the line pressure and shifts but was looking for a little more clear reply. im not trying to throw in a wrench into a gearbox just learning. cause dtt uses single disc converters and most others are standing by triple disc. and i know what a dtt drives and shifts like and its awsome, but so was mine, not quite a dtt but impressive at least.





thanks

matt

 

[DavidTD]

Ok, you guys asked for it... :-laf



I guess my take is each owner will have their own expectations as to what is good and what is bad. So what I like, is not possibly what you will like.



I have had dealings with all 3 vendors. I think all 3 are light years ahead of stock. As far as what I prefer, as Mark said it is to lock. I have had a billet converter for a long time. 1st with my stock factory transmission and modified valve body, then with a locally built transmission and VB and a Pro Loc triple, and now a full Sun Coast transmission with Pro Loc triple. But here is what I hace experienced.



Jeff Garmon has been dealing with Joe Webb and Sun Coast since before there was an ATS or DTT or even a TDR web page for that matter. Along the way, Jeff was 1st to the 12's, 11's,10's and 9's all with a factory transmission built by Sun Coast. During this time, I recall only 1 input shaft failure.



In the beginning efficiency was 1st addressed by Joe. While it had advantages, it also had it's disadvantages. While Joe still has very efficient converters available, I think he would tell you they are not the best of both worlds, hence why he went to billet covers, then to triple disk with a little less efficiency, still keeping a big improvement over stock. Joe has always worked real well with Jeff experimenting with "new ideas" to improve things. Here is what I experienced 1st hand.



I'm sure you all remember the little Dakota Jeff built. That was my race truck and I tried different converters with it. In Muncie the last year it was there, I was trying a "tighter" converter. I had a heck of a time building boost before the truck wanted to blow the tires out. I locked the Dakota in 3rd and 4th nearly every time I raced it. The result was l lost nearly . 5 seconds off my et with this converter. I changed nothing else out but the converter, back to the original stall, and got my ET back. It had everything to do with being able to build 3-4 psi at the line, and 10-12 with the one I liked.



As was stated here, loose converters result in a large drop in RPM when locking. This is tough on the lockup clutch material and will result in a slipping and shuddering unit upon engagement. Higher line pressures helped, billet covers helped more, triples helped even more as the demand for holding power has increased over the years. More efficency also helps save the clutch, hence why I believe DTT does not "need" a billet cover. Also why I suspect the DTT race converter is 93% efficient, because even their racers lock the trannies.



In a nut shell, more efficient converters transfer more power to the wheels in fluid coupling. This feels great, especially in the later 24v's and CR's where you have electronics controlling shift points. But there IS a penalty of more lag because for rpm to build, it requires more movement of the vehicle. Quick spooling turbo's are less of a problem than larger ones. IMO, I find the balance between the efficiency "I" like and couple that with a triple disk.



And while I have this wonderful audience, I'll add that I read all the time, don't build more than X amount of boost staging without billet shafts or you will break them. IMO, the hardest thing on shafts are 1st, blowing through your converter while locked in 4wd staging to build boost, and 2nd, locking in 1st gear. The more efficient the converter is, the more stress you put on the shafts while making rpm holding it against the brakes. Less efficient means it's easier to make RPM and boost with less stress. I've made many 30 psi launches with my transmission and Sun Coast triple WITHOUT any billet, and WITHOUT ever breaking a shaft or flex plate. Do I recommend this, no way. But I did it for years. I got my 1st billet with my latest transmission. But the point is, I could tell you I have not had a problem with a 30 psi launch on stock shafts and be truthful. But the 1st time someone tried it with a more efficient converter than I use, they would break it. How much rpm and boost you can build while staging will depend on how efficient your converter is.



Ya'll have a good one, and remember, I am not a transmission guy, don't build them, and have no qualifications on this subject. So you just wasted your time reading this very long post. :-laf Or maybe not.

 

[Sled Puller]

Ok, you guys asked for it... :-laf



... . Along the way, Jeff was 1st to the 12's, 11's,10's and 9's all with a factory transmission built by Sun Coast. .

That needed repeating, I don't think Jeff has got near the credit he's deserved.



What flex plate does he use?

 

[justinp20012500]

These threads are fun. :-laf

I agree!!!





I ran a single disk billet TC with a DTT stator when I was at 385 RWHP. I like it on the racetrack, but getting a heavy load started, or backing something up an incline it just SUCKED!!! It would blow smoke for 30 seconds before the truck moved. Driving around town with out blowing smoke was also a challenge. (4500 ft elev. )



I am now running a multi disk TC with a DTT stator. Now that I have a ton of power and quicker turbo response everything is well.



SO. You need to define what you are going to use your truck for and how much power you want to finally end up at.





O ya, Stefan. I can build a billet (One piece cover) multi disk TC for less then you can build a single disk TC. That’s why some people out there are using the "Mexico" stator.



The "Mexico stator" is much lower stall then stock. So someone that is at 350-400 rwhp, that stator is a very good match for the work horse trucks out there that tow heavy and still want to have fun on the track.



I am getting ready to "go through" my trans and replace all the seals, clutches, and a few other parts with DTT's rebuild kit.



But not for a million dollars would I trade my multi disk converter with a DTT stator. That’s going back in. (Well maybe a million :-laf )





Every trans vendor out there has great stuff. BUT you have to use the right tool for the right job.



Mix and match if you have to. Take all the good points from one vendor and apply it to another.





I would like to present a challenge. Jeff Coan has a TC dyno. Lets take all the TC's we can get our hands on and dyno them in lock and fluid coupling using the same pressure for every unit.



DTT = best efficiency in fluid coupling mode (Not locked up)



Multi disk TC = most amount of torque/power held in Lock up



BUT if you take the good fluid coupling of a DTT and use that technology in a multi disk what do you get?? One great and efficient torque converter.







Justin



Not affiliated with anyone or anything.

 

[Mark_Kendrick]

Justin,

I agree on the stall. That's not how I set my truck but when I call to order a TC I ask for a stall to match the turbos on the truck. If I'm running big stuff I get a higher stall. Lower hp = lower stall. The lower HP trucks usually have faster spooling turbos and need less rpm to 'get lit'.

 

[justinp20012500]

Justin,

I agree on the stall. That's not how I set my truck but when I call to order a TC I ask for a stall to match the turbos on the truck. If I'm running big stuff I get a higher stall. Lower hp = lower stall. The lower HP trucks usually have faster spooling turbos and need less rpm to 'get lit'.

I agree 100%.



You have to get the stall for the right HP.



Too much HP and you will blow through the stall.



Too little HP and the truck will be a smokey pig that can't pull itself out of a wet paper sack. :-laf

 

[John_P]

David:



Great post buddy! Everyone that knows me here knows which

transmission I run and why. I have had excellent service from my

ATS TripleLok and the unit in my 1996 Dodge CTD now has over

90,000 very hard miles on it including heavy towing in the

mountains, over fifty drag race launches and so many street

and highway races I have lost count.



--------

John_P

 

[DavidTD]

Wow, long time John. How have you and the Chromed Cummins been doing? I still think you have too much Chrome so I will be bringing tools with me next time I see you to remove some for ya...



I hope you have been doing well. Johnner got that CR over 600 yet? How about you, dyno that masterpiece yet?



Looking forward to seeing you next go round.

 

[I-6DZL]

Mark, David, and others that have input their personal feelings and real world experience... ... I CAN'T THANK YOU ENOUGH!!! Mainly for keeping this thread clean and by the rules so it didn't get locked. I can't tell you how much i've learned from this thread. David really hit the nail on the head with his post by related a TC to its intended purpose. Thank you sir.



Curtis

 

[Graphic man]

I am no trans expert but i did spend a lot of years Drag racing with automatics and i can tell you i went through about 6-8 converters before i got the stall i wanted. in my case i needed a 5800 rpm stall because i was running a chevy 331ci roller motor and i need the RPM's to launch the car, small ci low torque high HP

hp level and torque curve has everything to do with a converter

every car and truck is different, cid, Vehicle weight, compression, cam, heads, tire size, rear end gear etc. etc

there a lot of CTD out there with a lot of different hp and torque. so IMO one size does not fit all, torque is what gets the vehicle going. HP will not launch a vehicle. torque does, and a lot of people get that confused

lower TQ - looser conv.

Higher TQ - tighter conv.

but loc-up is loc-up and it should not slip there.

so knowing your HP and TQ before ordering is the key to get the right one,

all converters are going to act differently in different vehicles.





Just my 0. 02

 

[John_P]

David:



Thanks for the reply! Yeah it has been awhile hasn't it?



Everything going well. My newly rebuilt 96' 12 valve (with alot of

chrome :-laf ) dynoed at 674 H. P. (uncorrected) on a Mustang

Dyno David. Johnner is very close to 600 now having run 556

on your dyno @ the Scheid Rally and 588 since then on another

Dynojet 248 but with a small "40 shot" of nitrous!! He still has

the stock injectors on his David!



How are you and your family doing?? I hope very well!

You coming to Scheid with your dyno this year??



Take care David!



--------

John_P

 

[DavidTD]

David:



Thanks for the reply! Yeah it has been awhile hasn't it?



Everything going well. My newly rebuilt 96' 12 valve (with alot of

chrome :-laf ) dynoed at 674 H. P. (uncorrected) on a Mustang

Dyno David. Johnner is very close to 600 now having run 556

on your dyno @ the Scheid Rally and 588 since then on another

Dynojet 248 but with a small "40 shot" of nitrous!! He still has

the stock injectors on his David!



How are you and your family doing?? I hope very well!

You coming to Scheid with your dyno this year??



Take care David!



--------

John_P

674 hp and I had to ask? Oo. My goodness.



Yes I will be at Scheids this year with dyno.



The family is doing well. We seem to be busy, me working my job, the dyno, then trying to get as much time in at the shop as I can. Penny's business is growing, and Morgan is growing like a weed. And has her mom's temper. :-{}



Jeff has a couple of test to do on my truck Saturday that I can't wait for. Last week he took his 94 2500 280k miles shop truck, 160pump with zero plate, a set of 370's and a stock HX35-14 turbo and made 497hp/1160Tq at 38 psi. EGT's were even not out of site, I never saw 1200 degrees on the dyno run. He's gonna tune mine the same way to see how it works with twins and 60 psi. Is Saturday here yet. :-laf



Can't wait to see you and the rest of the crew.

 

[I-6DZL]

Graphic Man from what i gather from David and Mark is that turbo spool up is more of a deciding factor than anything else. Could be right, could be wrong.



Curtis

 

[Graphic man]

Curtis

you are right and the turbo helps build TQ the smaller the turbo the faster it spools up and the larger it is the slower the spool up, larger INJ. and RPM will help you get the turbo spooled up too and a timing box rear end gear etc. etc.

the more stall the converter has the more it will stall until loc-up

it all depends on your set-up tq#'s and HP#'s

Ex. 89% converter. you have 11% slippage until loc-up

there has to be some slippage or you would put it in gear and it would stall the motor.

you could over come a larger turbo and a tighter conv by building boost at the launch ex. 10-20 lb of boost depending on your set-up and your trans if it will take it.

i ran a trans break in the car it would lock drive and reverse together

with a push of a button, that way i could bring the RPM's up to around 5800

and when the tree went i let off the button and it would launch the car really hard. i was also running a 5:38 rear gear, but again you need a good trans to handle it

 

[Stefan Kondolay]

Justin,



I'm sure if someone asked my Dad (Bill @ DTT) if he would build them a TC with our stator and a Billet Cover/3 Disk he could, he just doesn't recommend the 3 disk because it hasn't held more power than the current DTT single and it weighs more which means it would be slower and will be harder on flexplates. But for those who want that he could build it and probably for the same price as what companies are charging for the Mexico stators 3 disk TC.



We build custom stuff for guys all the time all someone needs to do is ask.

 

[justinp20012500]

He just doesn't recommend the 3 disk because it hasn't held more power than the current DTT single and it weighs more which means it would be slower and will be harder on flex plates.

So you are saying that if we put a DTT single and multi disk on a CONVERTER ONLY dyno and feed both with equal pressures. Then apply lock up, the DTT single will hold as much as a multi disk TC?????

But for those who want that he could build it and probably for the same price as what companies are charging for the Mexico stators 3 disk TC.

PM me for a price on a DTT made multi disk with a 89% stator.



I would tell you how much mine cost, and how much DTT charges for a single but I think it would be against TDR guidelines to openly discuss price.

 

[Sled Puller]

Mexican or Canadian, its all foreign, so whats the point?