PCM's effect on performance

[mrd]

I have a 95; came with 4.0 OHV and 4R55E. The PCM manages the engine and also the transmission, including controlling shift points. My vehicle could use some tweaking on the shift points.

There's a product called the Baumannator TCS:
http://www.becontrols.com/products/tcs.htm
This gives you precise control over the electronic transmission, unfortunately they currently don't support the 4R55E, only AOD-E, 4R70W and E4OD.

There's a product called the TruSpeed Speed Signal Recalibrator made by Superlift:
http://www.superlift.com/products/misc/truspeed.asp
It allows manual adjustment of the speedo gear's signal prior to reaching the PCM/instrument panel. I was wondering if anyone has used this and if it made much of a difference in shift points. My tires are almost stock diameter, maybe off by an inch.

I was also wondering if anyone has done any reverse engineering of the PCM circuit. Not the PCM itself, but all of the signal inputs and outputs. It would be an interesting exercise to build a replacement PCM, and could use any information that has already been accumulated on it.

 

[aldive]

I was also wondering if anyone has done any reverse engineering of the PCM circuit. Not the PCM itself, but all of the signal inputs and outputs. It would be an interesting exercise to build a replacement PCM, and could use any information that has already been accumulated on it.

That is exactly what a good chip/tune does. See http://www.bamachips.com/

 

[mrd]

That is exactly what a good chip/tune does. See http://www.bamachips.com/

I'm pretty sure all products in this category merely attach, or supplement, the existing PCM. They plug into a proprietary extension socket on the back of the PCM, or they modify flash data inside the PCM to guide how it manages the vehicle. These companies likely sign a contract with Ford to get the specifications for interacting with the PCM via this port. I was referring to completely replacing the PCM.

 

[spindlecone]

I'm pretty sure all products in this category merely attach, or supplement, the existing PCM. They plug into a proprietary extension socket on the back of the PCM, or they modify flash data inside the PCM to guide how it manages the vehicle. These companies likely sign a contract with Ford to get the specifications for interacting with the PCM via this port. I was referring to completely replacing the PCM.

Just curious, what would you attempt to achieve by replacing the the PCM

 

[mrd]

Just curious, what would you attempt to achieve by replacing the the PCM

This would establish a central hub of vehicle performance information and control. The existing input sensors could be supplemented with additional device inputs.

We can likely improve both the time and amplitude resolution of input sensing, that is we can read sensor values more frequently and accurately. This provides the opportunity to develop better statistical analysis of the physical state of the vehicle and to respond in a more appropriate fashion, given the stock sensors.

This combined with additional sensor inputs would facilitate a better ride; smoother running engine, better mileage, better shifting. This is assuming good algorithms are implemented to do so. I'm sure I can develop those algorithms, this is an area where I excel.

In addition, new user functionality can be established, as we can now easily interface and manipulate anything that the PCM once did, and we can manage these functions intelligently via software. For example, optional manual shifting (press a button to enable a slapstick, press again to revert back to computer control), which can also monitor the manual shifting to prevent disastrous shift attempts. Since we now have an interface to the GEM we can also control electronic door locks and power windows. This could be used with a remote so with a press of a button, all doors unlock and windows roll down, press again and all windows up, lock and alarm enabled. We could also use a bluetooth sender to automatically unlock the driver's door when you walk within a few foot range.

I've also considered replacing the stock instrument panel with backlit LCD screens. These could provide a very nice flashy interface for displaying vehicle status, and could also be touch screen for access to detailed information, or changing display options. Mate the LCD with an enhanced graphics controller and you can have some flashy displays on that instrument panel too.

Control of shock dampening and ride height could also be intertwined into the system. For instance, slam on the brakes and the front shocks stiffen, have the suspension lower as vehicle speed increases, etc. Basically ARC but can be enhanced with additional vehicle input and intelligence.

I know this all sounds crazy but it's actually possible, just takes some time to find the right hardware (there's alot out there) and proper planning and coding skills.

 

[spindlecone]

Far over my head but not crazy at all, Look at the high end beemers, they do most of what you envision.
Work on it, from acorns mighty oaks grow, keep us posted

 

[mrd]

I'm a shade-tree mechanic. I've done some automotive work, but not much. Most of my experience and knowledge lies in software, chips and electronics. I could use the help of some knowledgable experienced mechanics that I've seen in these forums. I'm not very familiar with engine dynamics and their insight would help tremendously in development of the circuits and algorithms. You'll see some questions posted if I do pursue this, for sure..

 

[Glacier991]

Well you will be right at home when we finally start multiplexing our signals in cars.... that is the next HUGE step.