Stand Alone Engine Management

[Axianator]

MS is MAP, so you could do away with the MAF. Can a Tweecer add fuel according to boost levels?

Indirectly, yes.

 

[UnderPSI]

Indirectly, yes.

Explain a little would you?

 

[Axianator]

When I say "indirectly", I am referring to the fact that there are no actual boost-related (or boost-referenced) functions or tables in any of the V6 SHO calibrations (whether it be the X2J calibration for the '92-'95 MTX or the D4U1 calibration for the '94-'95 ATX). Even so, there are ways around this restriction if you have the proper tools (e.g. a TwEECer RT and some time spent with your datalogs). One such method would involve measuring and plotting the average amount of boost for a given engine load and then, using the approrpriate fuel tables or functions, add or remove fuel at the engine load to acheive the desired A/F ratio.

 

[Axianator]

When I say "indirectly", I am referring to the fact that there are no actual boost-related (or boost-referenced) functions or tables in any of the V6 SHO calibrations (whether it be the X2J calibration for the '92-'95 MTX or the D4U1 calibration for the '94-'95 ATX). Even so, there are ways around this restriction if you have the proper tools (e.g. a TwEECer RT and some time spent with your datalogs).

One such method would involve measuring and plotting the average amount of boost for a given engine load and then, using the approrpriate fuel tables or functions, add or remove fuel at the engine load to acheive the desired A/F ratio. Obviously, this method is not as ideal as having a set of boost-specific fuel functions that add or remove fuel for a given amount of boost, but, if programmed properly, it would be more than adequate for most forced induction setups out there.

 

[AutoSHO]

I feel like I should mention something here...

The TwEECer is a great tool if you want to keep the stock junk ford Engine Control. And that, IMO, is exactly what it is. The driveability, even on a stock SHO, leaves much to be desired and is far from perfect. The sensors are sensitive and fail fairly often. Comparing it to any aftermarket standalone you're going to find the EEC to be much harder to tune (and learn how to tune) and its learning habits are terrible. I've driven 2 different SC SHOs and, under the same conditions, had them run completely different AFRs just by restarting them.

A standalone (especially a MAP based one) may not be a perfect tune but it will hold a tune a LOT better than the Ford stuff, and it does what you tell it to as opposed to what it 'learns' itself how to do. If I was playing with a lot of power, I would ditch the Ford stuff just for reliability's sake... Especially with the newest round of standalones having the wideband input capability to make them basically tune themselves (except, unlike the Ford stuff, they do it accurately).

Just my 2 cents, of course... I've dealt with the TwEECer for a long time and its a great tuning tool - I just think that the computer it is piggybacking onto is not a particularly stellar piece of work. Go drive a Bosch motronic equipped car and you'll notice a huge difference.

 

[Axianator]

While everyone is entitled to their opinion, I feel I should correct a few points here ...

The TwEECer is a great tool if you want to keep the stock junk ford Engine Control. And that, IMO, is exactly what it is.

Given the fact that the miltiary-grade Ford EEC wasn't just a random happenstance of electronic engineering (rather, it was a carefully-designed piece of electronic equipment), I would have to disagree with the statement that the EEC is "junk".

The driveability, even on a stock SHO, leaves much to be desired and is far from perfect.

These well-known issues can be attributed to the factory programming and not the EEC itself.

The sensors are sensitive and fail fairly often.

Possibly, although when it comes to any car as old as the V6 SHO, sensor failures are an eventual fact of life. What makes the problem worse is when someone attempts to save money by replacing a failed factory sensor with a questionable aftermarket alternative rather than replacing that factory part with an OEM equivalent.

Comparing it to any aftermarket standalone you're going to find the EEC to be much harder to tune (and learn how to tune) and its learning habits are terrible.

It depends on the basis for your comparison. In and of itself, the EEC is not that difficult to tune. The big problem for most self-tuners has been the lack of consistent documentation for both the EEC in general and their specific calibration in particular. This is another well-known problem that I hope to remedy this year with the previously-mentioned SHO-specific tuning primer and TwEECer FAQ. Even so, people must realize and accept the fact that with almost any system, there is going to be some sort of learning curve associated with understanding and programming the system to fit one's needs.

As for the EEC's "terrible learning habits", these habits may (again) be attributed to a) a lack of access to proper adaptive control functions, and b) poor or non-optimal programming on the part of the factory engineers. With the proper access (which is possible on almost any EEC calibration), the factory adaptive control strategy can be made to perform much better than stock - all it takes is some time, patience and access to the right parameters.

I've driven 2 different SC SHOs and, under the same conditions, had them run completely different AFRs just by restarting them.

Again, this is not due to the EEC itself, but rather the programming with which it was given (or a lack thereof) and placement of certain engine control sensors (namely the MAF, in this case). The EEC is only as good as it's programming and the setup with which it has to work. That said, you can't run a draw-through MAF in a blow-through configuration such as the SHO Shop's and expect the EEC to respond in perfect fasion.

A standalone (especially a MAP based one) may not be a perfect tune but it will hold a tune a LOT better than the Ford stuff, and it does what you tell it to as opposed to what it 'learns' itself how to do.

Again, this has to do with the factory adaptive control strategy (see above).

If I was playing with a lot of power, I would ditch the Ford stuff just for reliability's sake... Especially with the newest round of standalones having the wideband input capability to make them basically tune themselves (except, unlike the Ford stuff, they do it accurately).

If one does not need or want the factory adaptive control strategy to make alterations to their fueling mixture, then all they have to do is disable the strategy via software (which is possible on the V6 SHO using the current release of the TwEECer software). From there, you can use your TwEECer/SnEEC/datalogging tool to obtain whatever wideband readings you need/want and then apply them via the TwEECer.

Just my 2 cents, of course... I've dealt with the TwEECer for a long time and its a great tuning tool - I just think that the computer it is piggybacking onto is not a particularly stellar piece of work. Go drive a Bosch motronic equipped car and you'll notice a huge difference.

True, a piggyback solution is not always the best way to go, but when it comes to the EEC-IV, you have to work with what you have. I've read what the MegaSquirt can do, and while it is a very impressive DIY solution, it still cannot completely touch what the factory EEC is capable of.

Bottome line - the EEC is more than capable of "hanging with" or even outperforming most of the existing standalone systems. The reason why it has fallen behind some of these systems in recent years is primarily three-fold:

a) a lack of software access to the much of the factory code (as is the case with the V6 SHO),
b) a lack of understanding about how the EEC interacts with itself and it's engine control components
c) a lack of proper programming to control the engine in the manner desired

This is one of the primary reasons why I do what I do with the TwEECer - to unlock and understand as much of the factory code as possible and, in turn, put that same access in the hands of the community. If the public really knew how the EEC was actually programmed from the factory (instead of going off the bits and pieces that have been dribbled down from the tuners throughout the years) and what all it was truly capable of, then they wouldn't even consider an aftermarket stand-alone system.