im looking to get an f250/350 4x4 and do alot of mods to it and stuff, and eventually throw a...dare i say cummins in it. i will be having the transmission built up and stuff either way. i planned on getting a 02 7.3 and getting the 4r100 done by BTS, but is the tourqe shift 5spd auto better (also built up) like would it tow better and anything like that?

 

still wondering which tranny is better 4r100 or the tourqe shift 5r110 i think it is?, both will be rebulit stronger.

 

The 5R100 is a stronger transmission IMHO. Your problem will be you can't bolt it up and make it work behind a 7.3 engine. At least I've never heard of anyone making it work. Totally different electronics between the two.
Joe

 

yeah what i meant was i was planning on getting a 7.3 and it would have the 4r100 but since i will be putting in a cummins after a year or so i was wondering if it would be to my advantage to get a 6.0 with the tourqe shift instead.

 

A 4r100 built by BTS works great behind a Cummins. Rocky Horn of Rockin-S Performance here in Denver has a '79 F-350 powered by a Cummins 12v with a BTS trans behind it and recenly he ran a 13.1 at 101 mph. Not too shabby. Next summer he's shooting for low 12's with that combo.

 

The TorqShift is a great trans. Having the extra low first gear will help your launches. The top two gears are identical ratios to the 4R100, so at highway speeds it is identical RPMs to the 4R100.

The hard part would be making the TorqShift work with the Cummins. Nobody makes a stand alone controller for the TorqShift, and I'll be nobody ever will. It's too complicated. The stock computer won't run the trans unless it is running the engine, too, and it won't run a Cummins.

 

thanks mark i was hoping you would post here. however i have found a controller for the 5r110 http://www.pdfdownload.org/pdf2html/...pdf&images=yes

destroked.com has one for 850 and claims it will control the 4r100, 5r110 and some GM.

does anyone know a good shop that builds up the 5r110? i know bts is probably the best for the 4r100

 

Yeah, right. Buy one and let me know how it works. I'll wager it doesn't work at all. There is NO WAY that a universal controller can control any transmission. You're going to need at least an engineering degree and maybe a software engineering degree and a few thousand hours to make this piece of ____ work. It's NOWHERE near as simple as plugging in a universal controller.

Ditto.

 

yeah have my doubts about it thats why i posted, but it says they have programs depending on tranny you have. and basically its universal controller because they have different tunes for different trannys.

 

It's WAY harder to make software shift a TorqShift than a 4R100, due to the design of the two transmissions.

The 4R100 is an all non-synchronous design. This means that for each upshift all that happens is a clutch is applied. All you need to do is control the pressure to the oncoming clutch and you're all set.

The TorqShift is MUCH more complicated. The 1-2 and 5-6 shifts are the same, they are non-synchronous and all you need to do is control the pressure of the OD clutch. The other shifts are the problem.

The 2-3 is a swap shift. This is a special catagory of difficult shift. I believe Ford is the only trans maker in the world that still does swap shifts. Others have put swap shift transmissions in production and then replaced them within a few years. To make a swap shift the TorqShift needs to release the OD clutch to downshift the OD gearset while applying the intermediate clutch to upshift the Simpson planetary gearset. This is an upshift and a downshift occuring at the same time in the same trans. From my experience these two shifts MUST complete within 30 milliseconds of each other or it's going to feel awful. If the OD releases too soon the engine speed will flare. The amount of flare is dependant on how much sooner it completes. If it completes before the intermediate has enough capacity the trans goes back to first gear! Then it has to make a 1-3 shift. A few WOT 1-3 shifts means the trans comes out to replace the intermediate clutch. Been there, done that. If the OD releases after the intermediate comes on you end up in 4th gear (1.09:1 ratio) then downshift back to third gear (1.54:1 ratio.) Either way it's really bad.

Now if you made it though that you need to make a 3-5 shift. 4th gear is the 1.09:1 ratio that really isn't used. The 3-5 is a synchronous shift. It's timing requirements are about the same as the swap shift, but there is no downshift. To make the shift the intermediate clutch has to release while the direct clutch applies. If the intermediate releases too soon you get an engine speed flare. If the intermediate releases too late you get a tie up. A tie up is when all three pieces of the planetary gear set are held from turning. This means the output shaft of the trans STOPS. That's not a pleasant thing to have happen when you're at WOT making a 3-5 shift. You can lock the wheels on an upshift! I've done this, too. You can also break expen$ive parts doing a tie up.

Now start thinking of the combination shifts that can happen. How about cruising at 55 MPH behind some slow poke on a two lane road? A passing zone opens and you floor it. Now you may want to go from 6th to 3rd gear. You need to release the direct clutch and apply the intermediate. That's a synchronous shift in reverse.

As you can see from just these few examples it isn't a trivial task to make one of these transmissions shift. It's what I did at Ford for quite a few years, three of them working on the TorqShift. I'd be really surprised if anyone makes a controller for the TorqShift that works really well. I think someone could make one that does some basic shifting, but getting one so that it shifts at least as well as a stock trans is going to be a HUGE task.

 

cool thanks mark, you definatly made my decision alot easier, the torqehift is pretty complicated, and oviously not worth the hassel trying to pair it with another engine.