So, what's the consensus on what's legal for engine management in STU and ESP? Here are the relevant rules from the 2004 Rulebook:

ESP:

"Alternate computer control modules may be used whenever an equivalent change to the conventional system is allowed...Direct turbocharger boost control by alternate computer control is not, since there is no equivalent mechanical allowance."

"No changes are allowed to waste gates, pressure sensors or their location, and to other turbocharger or supercharger boost limiting systems"

STU:

"The engine management system parameters and operation may be modified only via the methods listed below...These allowances also apply to forced induction cars, except that no changes to standard boost levels, intercoolers, or boost controls are permitted Boost changes indirectly resulting from allowed modifications are permissible, but directly altering or modifying the boost or turbo controls, either mechanically or electronically, is strictly prohibited."

"1. Reprogrammed ECU may be used in the standard housing...Altered engine controllers may not alter boost levels in forced induction engines."

"2. Electronic components may be installed inline between an engine's sensors and ECU. These components may alter the signal coming from the sensor in order to affect the ECU's operation of engine management system. Example: fuel controllers that modify the signal coming from an airflow sensor."

Based on these rules, I've concluded the following about some of the more popular options:

1. ECU Reflash (Dynoflash, Xflash, etc.):

STU: Definitely okay so long as boost control is not changed. So, the average reflash (Dynoflash Fireball, etc.) would be illegal because they change the control of the boost solenoid to reduce boost taper, but theoretically an STU-reflash would be possible. Also, since MAF-trigger fuel cut might be deemed a boost limiting function, this should also be left alone (usually not the case with a reflash).

ESP: Probably not legal. The stock ECU is definitely one of the stock boost limiting systems that cannot be modified since it controls the stock boost solenoid and a reflash is not an "alternate computer control module" (which sounds much more like an SAFC, MAF translator, etc.) The fact that reflashes are explicitly allowed in ST, and even specifically allowed for both naturally aspirated and turbo cars, but that this same allowance doesn't exist in the SP rules also tends to support their illegality in SP for turbo cars. While reflashes are generally okay in SP, it appears to me that there is an exception for turbo cars when the stock ECU controls boost.

2. SAFC

STU: Definitely okay for STU because #2 explicitly contemplates this type of device.

ESP: Okay because it's an "alternate computer control module" and affects only fuel/timing, which are permitted mechanical allowances in SP.

3. UTEC

STU: Definitely not legal. It's not a permitted reflash and since it controls timing directly like a stand-alone and it isn't an electronic component inline between the engine's sensors and the ECU.

ESP: Definitely not legal unless it can be installed such that it can't control boost and can't disable fuel cut. If not, its installation involves an electronic change to the stock turbocharger boost limiting system. It may be possible to make the UTEC pass the stock boost signal through without any change, but that wouldn't be any more legal than someone running an SAFC in stock class and zeroing out all the settings.

4. XEDE:

STU: Since it doesn't drive the ignition directly, it should be okay so long as it is installed so it can't control boost and can't disable fuel cut. It is basically an overgrown SAFC in this configuration (I think -- I'm not that familiar with the XEDE or its upcoming firmware update).

ESP: Same as UTEC.

5. Standalone (AEM, etc.)

STU: Obviously illegal.

ESP: Definitely illegal because it requires the removal of the stock boost limiting system (the stock ECU).

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I admit that I'm reading the rules conservatively, but unless there is a pre-existing consensus or SCCA interpretation to the contrary, I think that we can expect the competition to read the rules as narrowly as possible.

Okay, what are everyone's thoughts? If you think I'm misreading any of the rules, please explain your logic.

Thanks!

 

I think your interpretation of the rules is right on track...

 

The stock ecu controls boost? How?

 

Stock ECU controls the stock boost solenoid.

 

Well, duh, I just wasn't thinking. Don't I feel stupid.

 

The UTEC and Xede can be installed so the stock boost controls are maintained. In both cases the boost solenoid wires can bypass the piggyback unit.

 

I know that's correct for the XEDE. At least based on my XEDE & harness, it's actually easier to install the XEDE not to manage boost. The install which took a little over an hour would have taken less than half that if I had wanted the XEDE not to manage boost.

Specifically, two of the XEDE installation steps involve splicing into the boost control solenoid control wire, which is not part of the plug-and-play harness; and removing the brass restrictor "pill" near the solenoid itself, which must remain in place for ESP.

 

What about fuel cut issues with the XEDE or UTEC?

I remember reading a little while back that both of these units were being revised to directly drive the injectors. If that were the case, then they would circumvent factory fuel cut and potentially be protestable. Maybe if you had an older unit then you wouldn't have that issue?

 

I think the new firmware for the UTEC can completely take over the injectors. I am not running this firmware in ESP. As long as the fuel cut is not based on manifold pressure it can be modified in ESP.

 

Is everyone in agreement that a reflash is a no-no in ESP? That's the one conclusion that I reached that I thought was counter to the majority thinking.

 

IMO, a reflash is legal, as long as boost control functionality remains intact and unmodified.

My personal opinion is that the SP language is more permissive than the ST language, but coming from an embedded software development background, I may be interpreting a meaning on the word "module" which wasn't intended. To me, a "module" may include a map within the ECU (like a timing map, a fuel map, or a boost map); something which can be changed independently without directly impacting other functionality of the ECU.

From a practical sense, it's a difficult area, because of two difficulties -- (A) the difficulty for a protestor to convince somebody that you've got a reflash, and (B) the difficulty for anyone to prove that a reflash is legal or illegal. And even if your reflash is legal in impound, that doesn't mean it was legal on course.

Given those difficulties, I can't imagine what a protest committee would do if a competitor protested a car for an illegal reflash. The code and the data programmed into the standard ECU are not documented anywhere I've seen, and apparently there are multiple different programs for "stock" ECUs (supposedly there is an ECU code change for the P0300 fix). So even if you could dump out the ECU's contents and compare it to another known stock Evo, it's not guaranteed to match even if it's a legal unmodified ECU.

And if the "test" for an illegal reflash is to do some full throttle pulls with a calibrated boost gauge... If it comes back and says that you're peaking at 22 psi and holding 19 psi to redline, one could always argue that the extra boost is an indirect result of alternate spark/fuel mapping and legal intake and exhaust mods.


So it seems to me that reflashes are on the "honor system" -- explicitly in ST, and implicitly in SP -- mainly because I can't see any realistic way that a protest committee could handle a reflash protest.

 

Technically I think the ECU reprogramming might be legal in SP. It's pretty clear that it's legal in ST, but the problem that you have is how to verify that you have touched the legal parameters.

I helped (convinced actually) vishnu to develop the vishnu STX legal ECUTEK for the WRX. It's fairly easy to do, and incredibly easy to cheat. Therein lies the problem. Without a chip analyzer it is almost impossible to "read" the parameters off the ECU to verify that the boost control systems are not modified. The best you can do is profile the results to look for any indication that your running "illegal" boost mods.

The wording of the STX/STU rules are written to allow ECU reflashing on forced induction, or at least to clarify the existing rules in SP. Because of the inherit vaugeness of the SP rules, reprogramming the ECU is generally not an option because the SP rules do not distinguish between the boost table (and surrounding programming) inside the ECU from the ECU itself. So under SP rules, if you reprogram the ECU, then you have modified the boost control system, period no exceptions.

Under STX you have the exception

"1. Reprogrammed ECU may be used in the standard housing...Altered engine controllers may not alter boost levels in forced induction engines."

This explicitly allows you to reprogram the ECU while not touching boost control sub-systems in the ECU.

Again the problem is verification.

When developing the vishnu STX map, you run into many issues. For instance, on the WRX ECUTEK, your can now have multiple maps programmed in to the ECU. This allows you to "toggle" the maps on the fly. This is illegal under the STX rules because could have one legal map, and the other with modified boost maps hooked to a hidden switch.

So how do you verify this at the event? Currently the only thing you can do is datalog the ECU and hook up a "calibrated boost guage" and let the protest officials do some test runs.

The problem with reprogramming the ECU in SP is the wording of the rules. The ECU is treated like a giant black box under the current rules reguarding boost control systems, Given the highly politicized position we EVO drivers find ourselves in, I would say don't do it

Even under STU, this rule is highly contraversal

http://forums.nasioc.com/forums/show...+reprogramming

http://forums.nasioc.com/forums/show...+reprogramming

Like most others on nasioc have said, it's a safer option to use a piggy back system (Xede for instance) and disable the boost control feature. This can be done by modifying a Xede harness, which makes verification very very easy...

 

15.9.A says "Any ignition setting adjustment or system may be used"

15.10.C says "Carburetors, fuel injection, intercoolers and intake manifolds are unrestricted."

Aside from "boost-limiting systems" changes being prohibited, there's no wording that suggests ECU changes are anything but unrestricted. The caveat is that one would need to be able to show that the ECU-based boost controls were still in place.

Charles

 

About the STU legality:

One of the issues we've seen with the UTEC in the STX WRXs (and this would apply to STU) is the way the rules are worded... (Taken from a post on NASIOC)

Now I don't know how the UTEC works with the EVO, but I would imagine the very same thing occurs.... the UTEC in the WRX alters functions EXITING the ECU... which the rules state only signals from the sensor going to the ECU can be modified. (Not from the ECU to the UTEC)

The only other way around using a piggyback is a re-flash the stock ECU and then it still is a can of worms with "how the hell to you check for legality when the software in that reflash is being protected by the tuner that developed it?"

 

Well, Charles... In princible I agree with what your saying. but try proving that in a protest is another....

If your going to reprogram the ECU in SP, be damm sure that you have a bullet proof method to verify that no boost control systems were not modified. Since the ECU directly controls the Boost solinoid, it is therefore (by the wording of the SP rules), part of the boost control system. Since SP rules do not have the same wording at STX/STU, then good luck... your going to fight a up-hill battle (mount everest style... )

But you should know all this already from your experiance running the DSM.