Jime

iTrader: (10)

I am working on a mod to change the stock WOT shift points. Currently most of the trannies change at approx 6000 rpm and I would like to increase that to just below the rev limiter. Some cars show a 6500 shift but if you hook up an OBD-11 reader it will show the true RPM which is much lower is most cases.

You can manually shift but its almost impossible to get exactly the same shift point every time and when your car gets fast enough the 1st gear shift is virtually impossible. This way you can adjust your shift point to whatever you want and will be especially beneficial for raised rev limiters and take advantage of cams and intakes that raise the powerband.

The sensors that control the trans send out a pulse signal so they cannot be changed by simply connecting a resistor etc. What I am trying to do is change the signal with a "Digital Pulse Adjuster". The retail price of the adjuster and controller is approx $350 so I would like to see if there is any interest should I be successful. Without the controller ie fixed RPM it would be $100 less.

I have seen the Manumatic but it only allows for tiptronic type shifting. That is no help when you are trying to get consistent times and maximum performance to do that it has to be the same every time which this mod will do and no chance of missed shifts and hitting the limiter. If this works auto shifting will outperform manually shifting.

I don't believe anyone has done this before maybe because of the pulse type signal that needs to be modified.

NmexMAX

iTrader: (22)

I would be ineterested, but mainly for an A33B. Do you have any clue as to what exactly are the differences between the 2 ... and what would need to be altered... Sorry, I know this is the wrong forum to ask, but certainly the right person.



BTW, always liked and admired the work you did as far as the voltage/throttle opening % in the A33B. When you used 60% and still managed a high 13..

Jime

iTrader: (10)

It looks like its pretty much the same for the A33 after looking at the schematic so should work the same for it as well.

Ya no more drive-by-wire now so can't do that anymore, my 3.5 TB now looks like this.

Dubbya

iTrader: (16)

Very intrested. How would this work? We send you, say an ecu, and you upgrade it. Or do we need to buy the Digital Pulse Adjuster too?

NmexMAX

iTrader: (22)

TCM play any part in this?

chillin014

iTrader: (67)

i also appreciate your discovering for us auto's, im sure i would be interested if it was beneficial to me(something i cant determine). i have an intake but i dont know how much more power thats putting above the rev limiter.

Jime

iTrader: (10)

You need a digital pulse adjuster to change the signal but you do not necessarily need the controller unless you want to change the RPM setting. I may even try to make some after I see the complexity of the circuit board if I can do it cheaper.

NmexMAX

iTrader: (22)

With stock IM, you shouldn't need an extended rev limiter.

Though with the auto's tall gearing, it may help, but you would need a dyno for it. IIRC, people with near stock set-ups, such as yourself, actually benefit, or see no improvement in 1/4 mile time when letting the tranny do it on it's own, 6k shift.

Jime

iTrader: (10)

Yup sure does, it uses the pulse signal from the vehicle speed sensor on the transmission plus the rpm signal from the ecu (pulse also) and signal from the TPS.

NmexMAX

iTrader: (22)

But isn't this the ultimate goal, change RPM setting?

DandyMax

iTrader: (7)

No cruise on that TB Jim?

I hope the DPA ends up working for you... I'll be following this to see what happens (not that it matters for me, being a 5-spd, but if it does work potentially a useful mod for autos).

NmexMAX

iTrader: (22)

Another question Jime, what about the infamous 3rd gear lag? If you need me to further explain, I can, but I'm pretty sure you know what I'm referring to.

Jime

iTrader: (10)

What I'm trying to say is that if you have a digital pulse adjuster that has been set for a different RPM setting you wouldn't have to have the controller unless you wanted to change it again.

I guess what makes it confusing is the name digital pulse adjuster. Once set it will hold that setting until modified with the controller. They call it an adjuster because it adjusts the incoming signal then sends it on to the TCM. If you think about the S-AFC that adjusts the signal from the MAF to the ECU its exactly the same.

The 3rd gear lag is the converter locking up, if you leave the shifter in 4th it won't do that, it only happens when you leave it in 3rd. This only applies to the A33, the A32 does not do that.

Jime

iTrader: (10)

To much work to keep the cruise, would have to weld etc onto the shaft to make it longer, besides look at all the weight I saved.

I may need your help on the DPA Dan, just hope I can do it with one, it may take 2 but I hope not.

Tatanko

iTrader: (34)

This would be great, especially if it can be made easy to install. Will it just be a box we need to mount somewhere and connect into our wiring, or what?

$350 doesn't enthuse me a whole lot, but you said that's just if we want the setting to be changeable, right? This $100 item will allow us to raise the shift points, correct? (just not change the shift points once it's set, right?)

This seems like it will benefit those of us who wish to do some sort of VI but are stuck with an auto. This way, with an increased rev limiter, we'll be able to rev to whatever RPM we want with an auto

NmexMAX

iTrader: (22)

Good relation, thanks.

My A32 does that when left in 3rd (O/D off). To eliminate this in either situation, after the 2-3 shift, one would just shift to D... Easy enough.



I think the most benefit from this will be consistency...

Tatanko

iTrader: (34)

True, but I can't help but think of all the problems I've thought about (for example) VI's and owning an auto. I always though "Ehhh is it worth it if my tranny shifts at 6000?" (or if I have to inconsistently manually shift higher...which is your point )

NmexMAX

iTrader: (22)

I do not have a problem manually shifting @ 7000+ in 2nd with a VI, for the simple fact that it's very enjoyable .... With such tall gears, with the exception of 1st, you wont have any problems with tapping the limiter etc when in a 1/4 mile run.

I could only imagine how it would be with Jimes new set-up.

Jime

iTrader: (10)

It could be as easy as the DR mod except for powering the digital pulse adjuster. Correct the $100 controller would only be needed if you wanted to adjust it at some later point. But it would have to be set initially with it.

Hmm I don't remember the A32 doing that but I didn't really start holding 3rd till I got the A33. I have tried shifting to D after the 2-3 shift with varying results, sometimes it was ok and other times it did the same thing but at a different RPM. Here is a typical example you can see the lag right where I have placed the white line. Just leaving it in 4th it didn't do it at all. If this mod works then I won't have to worry about it any more.

NmexMAX

iTrader: (22)

They both do it ... But with the 32 you have to stay in 3rd to see/feel/hear it, well same goes for both.

I think holding 3rd until you feel the lag, and then going to D helps, because you can actually see those extra few hundred RPM's.







EDIT***

I feel like a moron ...

The entire point of this thread is to eliminate manual shifting, hence, I would never be in 3rd, or have to worry about shifting when I feel the infamous lag...


BTW, what's the X axis? time, what's the scale?

Jime

iTrader: (10)

x=time, scale is adjustable so not sure what it was there. You can see that I was just idling along in 2nd at about 3k and then nailed it and the a/f drops from 14.x to 12.x. I have tried a number of settings for the N/A a/f from 12 to 13.5 and 12.5 gave the same performance as the leaner settings so I just left it there. For the first time in 3 yrs I will be hitting the dyno in the spring to get the 3.5 tuned and try a bunch of stuff to see how it affects power.

Tatanko

iTrader: (34)

Well it's ok to be manually shifting in the 1/4 mile...but what if, say, I'm on the highway and want to want to go WOT? I'll be limited to 6000 RPM, if that, before my tranny upshifts.

C MAX

iTrader: (4)

man great idea jime, its almost impossible for me to use my extended rev limiter because my revs bounce so fast i dont have time to shift to the next gear and half the time i just redline at the track and it p*ss's me off. so now i just leave it in drive cause its easier to concentrate on my launch and spraying at the right point.

clive

If it is simply square pulses that trigger the shift, then it wouldn't cost more than a few dollars in hardware to adjust the shift point to whatever you desire.
Something like a Schmitt trigger to square up the pulse and remove noise, then a variable-delay monostable, like an NE555, no problem whatsoever.
If someone gave me the specs I dare say I could design a circuit without much bother.

ajcool2

iTrader: (43)

JIME you are the man. Always finding ways to give the 5speed's a run for their money. I would be interested in this my self.

NmexMAX

iTrader: (22)

I've yet to track either of my cars, all the manual shifting I do is to work and back ... Passing on the highway on the top of 2nd is nice with MEVI/7k.

Don't be lazy.

Too much uncertainty in this post ... Jime has a plan of attack, and he knows the system quite tremendously well. You're only going on electronics backgroung rather than actual experience using A32/33 so he's familiar with their TCM/ECU relation and characteristics. But hey, maybe you guys could collaborate on it.

96customax

interested in this also. Its time us auto's get something nice for our tranny''s

Tatanko

iTrader: (34)

Ehhh...I've just always told myself not to manually shift except starting out (i.e. 1/4 mile). You mean to tell me you manually downshift while you're on the highway? (other than O/D on and off) How do you do that? I thought you had to have the brake depressed to slide it into 2nd or 1st?

Having a nub moment

grey99max

iTrader: (12)

Well, sir - you've done it again.

If I may ask, have you found the relationship between the speed sensor pulse, the ecu rpm pulse, the TPS signal, and when the transmission actually shifts to the next gear? And are conditions the same for the 1-2, 2-3, and 3-4 shifts? Does this product perhaps reduce the rpm pulse rate as rev-limit is approached?

If this works, and can be adjusted to bring the 1-2 and 2-3 shifts up close to the rev limiter, sign me up! I've been launching my Infinity VLSD tranny with too much nitrous, but with the new Edge torque converter sitting in the front seat and my MEVI, raising the shift points would be ideal for next year's track season.

You're right about manual shifting being a waste - things happen too fast to be consistent - or safe.... This is a great idea - I hope you can make it happen.

Jime

iTrader: (10)

I don't have it all figured out yet but the idea is to reduce the rpm pulse rate for sure and because its just the signal being sent to the TCM it will have no effect on the tach or other rpm based functions.

Another thought comes to mind though it may also be possible to reduce the signal going to the ECU and raise the rev limiter. However that would affect the tach which I guess I could live with but would make it less attractive.

Good stuff on the converter, maybe I should be buying stock in Edge, I have one sitting in my workshop itching to be installed as well.

Tatanko

iTrader: (34)

In order to make the TCM think the engine is at lower speeds to make it wait longer to shift, I take it? Just trying to sort this in my head.

Can't anyone answer my question about manual downshifting, either?

DandyMax

iTrader: (7)

I'd have to check into the FSM a bit but off the top of my head I think you'd have to alter the crank signal(s). And even if that were possible with the DPA (the POS sensor is the only constant interval pulse pattern-the REF and CAM aren't), then you might run into problems with the phasing with the cam. And if that happens then the ECU will throw a code and retard timing (as per Joe's work with the SMT-6). And as you mentioned, the outputted signal to the tach could be off too.

Jime

iTrader: (10)

Dan sometimes I dream in technicolor. I was thinking about the POS for sure, never read all the SMT-6 stuff, maybe I should go look at that for a little insight. Its this cold weather makes my mind wander.

grey99max

iTrader: (12)

Did you talk to the owner, Andre, I think? He's got great stories about 30 years of racing....


Interesting - I haven't looked into a FSM yet, but if the rpm pulse feeds the TCM directly, and there isn't any critical need to keep the TCU synced to the ECU, then designing a circuit to reduce the pulse rate is possible.

Example - as the pulse rate approaches 5800 rpm, then the output doesn't change as fast as the input. 5800=5800 5850=5825 5900=5850, etc, until 6500 in = 6000 out. Humm... actually a VCO (voltage-controlled oscillator) could do that quite easily. Then, does each gear-shift work the same?????

I'll stay tuned - and I'll look at the FSM - I keep one at work.

Jime

iTrader: (10)

Ya I dealt with Andre, was going to ask you that too. He is the one that told me how to get the bushing out of the crank to get the 4th gen trans to slide in. He said to get something the same size as the inside dia of the bushing (I used a socket and extension) then fill the hole with grease and insert the socket extension and hit it with a hammer, after a few swats the grease pushing on the bottom of the bushing popped it right out.

I think first I will just try a constant reduction, like you say it doesn't matter if its synced or not. Just reduce it 500 rpm or whatever and see what happens. Getting it to work for all shifts may take some playing but I have all winter. Luckily I can use my wife's car to experiment as my engine is still on the stand awaiting cams.

DandyMax

iTrader: (7)

Haha Jim don't feel bad about dreaming in technicolor. That's often how great ideas are born-you've had a few already. And besides, I'll probably be going loony myself by the time winter's done. I've got a long list of things I still want to do on my car but can only sit here and think about them since it's in storage. Lots of unfinished business... ya know? lol

Hopefully I'll have a garage before next winter so I can actually work on it over the cold months. Too bad you're a bit far away up there in Barrie, or I'd be inviting myself over to help with your swap just to ease my own withdrawal. (well, I'm joking, but you know I'd help for non-selfish reasons too)

grey99max

iTrader: (12)

Oh, that's right - you're doing the 3.5L conversion plus the Ebay cams??? I really want to do this 3.5L conversion over the winter, so I'll file the bushing trick away for future reference.

Would you reduce the rpm signal to the TCU all the time, or just under WOT? Otherwise, partial-throttle shifts might get weird ? But nothing beats actually trying it out... Keep us informed, plz.

Edge built me a 3000-rpm-stall Street Edge converter with "carbon-disk clutch" ? that Andre seemed very familiar with - he was confident that it would launch stronger and pull better on the top end. He also said that with the 3.5L conversion that stall would go up 200 RPM - he seemed to know about the conversion, so I figured you or another ORGer had talked with him. Of course I won't know how it works until April....

ArcticW

Possibly a little off-topic, but wasn't there a post about there being a mod where you could wire a manumatic function into the transmission? That way, you could pick the shift points manually versus being stuck witha programmed sequence?

grey99max

iTrader: (12)

ArcticW, I think you're right - see Jime's first post in this thread - but the manumatic was an attempt to allow manual shifting from the wheel, which is not the same thing as convincing the automatic to shift at higher RPMS..... Things happen pretty darn fast on the track, so an automatic that always shifts at known RPMS would be a Good Thing..... and when you use lots of this:
things happen really quickly..

CreativeDesignz

iTrader: (3)

so ontop of this mod that you are trying to accomplish you would, if u had a VI or mevi, want an upgraded ECU as well so that u can shift around 7k or so correct, this could probably get pricey pretty fast. what about messing with something in the valve body? possibly softer springs? or maybe harder ones? this is a great idea none the less