Interested in limted external transmission adjustment ???

[jonseyq45]

Looking to see if there is interest in a external way to adjust the shift firmness. My brain hurts after thinking about this for a while. I work in an environment that has electrical engineers available for me to torture. What I am working on is a replacement for the transmission resistor. What I will replace it with is a box that contains an adjustable 10 watt rheostat (0-100 ohms) and a vacuum operated circuit. The rheostat is to adjust shift firmness during normal driving and the vacuum switch will allow full line pressure under full throttle (low vacuum) shifts. I have worked out the logic, now working on proof of concept. My question is would this be of any interest to any one else???

Jonesy…..

[qship96]

Why do you want to change the way the transmission shifts? Guess I dont see what benefits you are looking for?

[jonseyq45]

This would eliiminate the soft 1-2 shift and and due to the higher pressure allow the transmission to live longer. I am trying to allow a bolt-on solution and allow some adjustability

Jonsey

[qship96]

Soft 1-2 shift? In a nissan/Infiniti product? Most who complain,complain the 1-2 shift is harsh in these cars. Not sure you can adjust for worn out hard parts?

[96Qowner]

1-2 shift shouldn't be soft. It's typically nice and firm. It's the 2-3 shift that's soft.

[qsiguy]

I've been thinking about the same thing so I'm interested. What I've done currently is wire a relay to open the dropping resistor. It is activated by the stock kick down switch on the accelerator pedal. It works great and gives me much firmer shifts during WOT/full boost. Prior to this the shifts were slow and soft. Why to do this? Well with my added horsepower, that slipping during shifts generates heat in the transmission.

Issues: If I went WOT the next time I start the motor the TCU doesn't like me. I get the transmission malfunction display. It goes away after a few seconds when it realizes the resistor is there now. What I'd like to figure out is at what resistance the ECU will not detect a problem and will the shifts be any better at that resistance.

You would need to increase the resistance to increase the solenoid pressure. Possible adding a 2nd dropping resistor in series that activates upon WOT? Wonder if doubling the resistance would alter shift firmness.

Lets give this some thought, definitely.

[jonseyq45]

Ok Ok ....the 2-3 shift. As to the wot shift, when I have disconnected the resistor, the shifts were nice and tight. I will include adjustability as to when the the circuit opens based on vacuum pressure.

People have changed the resistor value, what I am working on is using a rheostat instead. This allows for adjustable resistance, also opens the possibility of a value based on throttle opening too.

jonsey.....

[maxnix]

Ok Ok ....the 2-3 shift. As to the wot shift, when I have disconnected the resistor, the shifts were nice and tight.

Never had a problem at WOT. I think this is symptomatic of varnish in the solenoid valve body.

I think TexasOil posted some information on why not to do firm the shift for clutch life.

[Kiven422]

I've been catchin up little by little on this subject and from my understanding (from previous posts) the 2-3 shift becomes perfect???

Its the 2-3 shift that bugs me the most. I hate to have to adjust the throttle for it to engage 3rd quicker and smoother, takes almost a second every time.