Getting ready to order a new transmission and triple disc torque converter and would like some input on converter stall speed. My engine has no modifications to it right now because I wanted to do the transmission first but I would like to eventually get a set of ATS twins. What kind of stall speed would best suit my application? Low stall (tight), Same as stock, or Higher stall (loose). The truck will be used mainly as a hot rod, just a fun vehicle to drive if I want to (which might be everyday if it is fun enough) but not a primary or tow vehicle. I also may try a Garrett stage 3 GT3788R or something similar before the twins. Other mods will probably include injectors and smarty.

 

As a rule of thumb, the lower the stall, the harder is is to spool the turbo. I have a very tight TC, but it is great for towing. You say you are hot rodding...I would not go higher than stock for sure, you are only heating up fluid and losing the opportunity to take advantage of the wonderful torque of the CTD.
I would recommend talking to a couple of builders, like Goerend, Dunrite, Suncoast to see what they say... chances are you'll end up with something between what I have (very tight) and stock. Splitting the difference in other words.

 

Mine is tighter than stock, but looser than what is considered really tight. I love it. My single turbo spools great and I have plenty of low end for towing. It's perfect for me. if you are running a 62mm turbo in your twins this would work well for you.

 

Can you guys post your stall RPM for him?

 

I am not really sure on mine... I did the brake test and came up with about 1450...

That is still a guess.

 

Why a triple disk?

 

A single disk can only hold so much power. A triple disk greatly increases the friction area of the TC clutch so it will hold much more power and not slip.

 

I would say 2200 would suite the ats twins rather they are the a3k and a5k or stocker and a5k. This isnt too loose imo but not really tight either. What trans. company are you going with tony at dunrite will make a converter how you want it and if you ever change the setup send it back to him and he will re adjust stall for free.

 

I held 1380 lbs TQ with a single and tow 26K

 

For a regular street driver/hot rodder that does some towing you dont want to go too tight. Your bottom end when towing will really suffer. You should shoot for about 250-300rpm below stock. With a stock truck you typically would see stall speed around 2100rpm. The peak of your torque curve is about 1800rpm. That is where you want to be right at the peak of that curve. Any lower than that and your really giving up lots in the bottom end.

 

running a suncoast 91% in an HTS trans with a silver bullet. works AWESOME together! silver bullet spools lightning fast, i would never look back to anything smaller. btw, i drive 800~ miles a week.

 

I have around 1800 stall if I remember correctly...EXACTLEY where I can make big boost with my top turbo!

 

Definitely go tighter then stock... but how much tighter is a preference thing. I prefer a pretty tight converter.

Also, i think it's a good move going with the triple. I used to be a die hard defender of single disc converters (i now believe i was wrong). I still think they are fine for most applications, but high hp requires a triple disc. Recent experiences (not he said, she said) have led me to believe that.

just my .02

Chris

 

Thanks for all the replies. I am sorry that I don't always reply to posts right away. I am 18 hrs ahead of Californiaan I am hitting the sack when most of you are waking up also last night my broadband was down . I am getting a Goerend full billet trans and triple disc converter. I have been communicating with Dave Goerend and he has been real nice to deal with. I just wanted to get some input from DTR members so I would have an Idea of what works and better info if he asks about converter preference. The reason I am getting the triple disc and full billet converter is because of how far away I am. If something broke and I had to send the trans back my truck would be down for a couple of months at least. I am just hoping to reduce that chance

 

IMO converter selection has alot to do with use of the truck, and turbo selection. If youre doing a loose converter to light a big single you will be using a lockup switch alot and if its high hp application look at replacing a billet input around once a year.