Is there something we can install that would electronically hold the transmission in a specific gear? For instance: Dyno runs in 3rd gear for newbies without downshifts; and maybe on the road course coming out of a corner under hard acceleration, so the tail doesnt kick out due to downshifts... I can think of other uses, but not important.

Just wondering if someone has something like this?

 

I d/k the answer to your question but I want to 'tag' along and ask another trans question.

1. Does it hurt our trans to manually downshift the trans from OD to third or to second at 70 mph?

2. Does it hurt the trans or add 'wear' to manually shift it into neutral while waiting for a long traffic light, etc.

Hopefully, Factory Tech will see this thread..............

Dan

 

Vyper, we can fully control the trans with our chips, however, to make a program that won't downshift for the dyno, would obviously be a dyno only program. When I tune trucks, I do this, but then change it back to normal when I'm done. To get the truck to NOT downshift the normal way, is bring it to 70mph on the dyno, then go WOT.

As for the other question, we can tune the shifting anyway you like, and I do programs like you mentioned for auto cross customers.

Dan, it doesn't hurt the trans to downshift like that. I don't like to go into 2nd over about 70-72 mph because the MOTOR will be screaming rpms . And it doesn't hurt the trans to put it in neutral at stop lights, if anything, I'd think it would lower fluid temps slightly since you are not hydraulically engaging anything.

 

Well here's my thought: to have a "control pad" linked directly to the chip/ecu. the control pad would probably need to have some of its own on-chip logic, but here goes: 4 lighted buttons, each linked to a gear (labeled 1st, 2nd, 3rd, 4th), and when any button is pressed, the transmission would just shift to that gear and hold it, and an indicator light would come on. To release the gear, you would either select a different one, or push the same one to go back to "automatic" mode.

I think it would be cool, and I'm not sure why :-) thanks for the responses!


~VyPeR

 

Chrysler Corporation beat you to it in the 60's with the dash mounted, pushbutton controlled Torqueflights. Very popular with the drag racers back then. Of course, it wasn't electronic; mechanical/hydrolic I think.

 

It doesn't hurt the tranny's to downshift into second at 70 mph. I've done it many times at 85 mph and I've been with Ruslow when he's done it at a higher speed. It won't downshift until it's ready. But, since you'll be in your braking zone, you'll have to get used to the truck getting a little upset when the rear tires chirp (the rear end will hop to the right also). Once you've done it a few times, you'll get used to it. The same is true with OD. For instance, the exit of turn 1 at Laguna Seca is a wild ride. I pop the OD button with a finger and unless you gas it, the rear end hops around and is very light.

As far as the upshifting is concerned, you've got a good idea. I don't think Bluesky636 understands your concept. Dashmounted buttons wouldn't give me much comfort at an arm-lengths away at speed. The OD button is bad enough on turn one while accelerating downhill. I can't imagine trying to push a button an arms-length away in a split second.

To adjust for the excessive downshifts, I found that holding back on the throttle (very slightly) at turn in and a gentle but quick application of it on the corners works best. After a few times, you'll find the sweet spot so you can get on WOT without the downshift.

One tranny item not mentioned is locking the converter. Have the chip tuned so it locks up when you get above 25 mph (for instance). That'll help keep it cool. In comparison to the downshifting at high speeds, heat and excessive shifting will cause more harm IMO.

One item to be aware of: Upshift into D LONG before you need to shift. If you don't, expect the engine to redline and shutdown. Been there/done that. Either that, or you won't have boost for about 1/2 lap. Sooner or later, it comes back, but it's spooky on the corners without any power.

Spike

 

I understand the concept perfectly. My only point was that pushbutton controlled shifting of an automatic is at least 35 or more years old. I never said that the pushbutton pad had to be mounted on the dash of a Lightning, although I don't know where you would mount it that wouldn't require taking one hand off the wheel and your eyes off the road to find the right button to push.

 

Inside the steering wheel, 1/2 at 9:30, 3 at 2:30, leave OD on the lever. The other idea is to bypass the torque converter (don't use one), add a manual shift valve body, and a clutch pedal to control fluid in the "pump." They're doing it with Powerglides. What about these trannies?

Spike

 

You don't disconnect the boost dump solenoid?

From another thread:

"It prevents the dumping(loss) of s/c boost pressure when doing a burnout(for launching at the track) or at WOT between shifts. You don't want to have lost your boost just before staging as it takes several(?) seconds to regain it---kinda like standin' there with your trousers around your ankles .

No repercussions since I disconnected the solenoid connecter 25,000 miles ago."

Dan

Just wondering.........

 

No. If I shift correctly, I've never had a problem loosing boost. After shifting late a few times, I learned to not shift late.

Spike

 

I dont have a lightning, I have a F250 PSD with a 4R100. I am looking for a way to shift my trans manually. I havent found anything on the PSD forums, so I thought I would check over here, since we have the same tranys. Here is a copy of the post I put on the PSD forum:

Does anyone make a kit or something that has a switch to allow the driver to control when the trans shifts. If not, how does the pcm tell the trans when to shift? Does it have a wire for each gear that is hot or grounded to tell it what gear to be in, or is it more complicated than that? If so, would it be possible to tap into these wires, to control the shifts manually? I am an electronics / instrument technician by trade, and have access to programable controllers, so if it works that way, it wouldnt be too big of a deal for me to do it.
What I had in mind was a gear vendor overdrive. I would control the shift of the trans and the GV with the Programable Logic Controller (PLC) Via a 2 position momentary Rocker switch of some sort (one position for upshifts, and one for downshifts). When the trans is in 1st and I hit the upshift button, the GV would shift into OD and the trans would stay in 1st. The next time I hit the upshift, the trans would go into 2nd at the same time the GV would shift out of od...and back and forth, giving me a 8 speed....get it? I would also have an auto switch, that would give the control back to the PCM. If this is even remotely possible, I would then have a few more questions..
Will the PCM be varying the pressures while it is trying to shift?
Do you think downshifting the GV and upshifting the trans at the same time will work OK?
If this wont work, could it be done by tapping into the gear selector controls, instead of the PCM control to the tranny?
I know this sounds crazy, but I just think the GV is a waste, if you cant use it in between gears.

Not trying to jack this guys thread, but I figure if anyone knew about this, It would be you guys. I would appreciate any help you could give me. Thanks!!

 

The answer is yes, it is absolutely possible to manually shift an electronic trans. on command. They are fully electronically controlled, each gear is selected by turning shift solonoids off and on. You have a really great idea here because the technology certainly exists. I work at a transmission shop and we have what we call a 'break-out box'. You plug it in and can either moniter what the computer commands vs. what actually happens (i.e. computer is commanding a shift, but the trans. won't), OR, you can command the shifts manually. It is an awesome diagnostic tool, but it's bulky. You ride with it in your lap, it's about the size of a Snap On scanner, so obviously you'd have to find a way to package it differently. Of course, you could always just have the buttons on the wheel and the computer mounted elsewhere, and without all the unnecesary diagnostic part and display screen etc. it wouldn't be near as big. If it could be done for a resonable price, that would be a helluva marketable product!

 

Ok. So is there a solenoid for each gear? Then the pcm energizes the solenoid for whichever gear it chooses? If this is correct, then I could just "break" into the wires to the solenoid, and enegize them manually...right? My next question is, does the pcm get feedback from the trans? If it is telling the trans to be in 2nd, but I have it in 3rd, will the trans relay this to the pcm, and turn on the ses light? What about pressures? Is the pcm controlling pressures at the same time? If it is, and I am shifting the trans manually, while the pcm is adjusting pressures, will this cause problems? I have all of the stuff to try this, but I just want to be sure I wont mess something up doing it. Does anyone see any problems with shifting one manually? Thanks.

 

I am not sure how relevant this is but here it is anyway:

For those of you thinking about shifting into second gear manually here is what Gregg Evans had to say on the subject:
This only applies to manually selecting second gear. If you have a chip that tells the computer to select second gear then it most likely would not apply. Just figured I would post it so everyone knows.

-Don

 

quote:
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The second gear is different in manual and automatic. When you're in "OD" (automatic) it engages the intermediate clutch to link the intermediate brake drum to the case and the sprag. When you shift it into "2" (manual) it engages the intermeditate band to lock the drum to the case, so it's totally a different route to lock the drum, which is effectively second gear. The band is not as strong or durable as the clutch plates.
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I would think that if you were tied in where the pcm was controlling the shifts that it would be just like the pcm was doing it. However, that definately rules out my other thought of tying in to the selector controls. Thanks