Proper tune?

[taurus6]

Ok, it's probably a fair guess that the majority of the modded cars not running properly is the tuning. Who knows what really is working first hand?

The Xede apparently does work, but still requires reflashing the ECU to not learn/adapt.

The eManage had compatiblity issues and/or bad boards according to other tuners. Has this been fixed?

Is it possible with a piggyback that is accurately tuned to the point that the ECU sees no need to adapt to have it work indefinitely?

What about the 02 mods, etc. that can spoof stoich to the ECU all the time and let the piggyback do it's thing?

I can't be the only one who had a car running perfectly with a turbo except for the stinkin' tuning going bad. Same for the N/A mods.

Any comments?

[scottyb]

I think the best approach would be to alter the 02 sensors output at times of boost. I was planning on conducting that kind of test but never got the opportunity. You would need to alter both the pre and post the same amount so that the ECU wouldn't start questioning the results. Also if done correctly the changing of sensor output would need to a graded change as boost increased. At first it might not be so smooth, but after the 05 ECU got to adjust the map in those areas it should be fine. No one really knows how well Lotus mapped those areas where the MAF sensor peaks out on the stock ECU, but the ECU will learn to adapt the map in that area. Just monitor your A/F and do a lot of testing before you jump to any conclusions.

[Buz]

It seems like the trick for na cars is to have the piggyback only make adjustments during open loop operation. The ecu will then not see the adjustments. Boosted cars need changes under part throttle operation so the ecu programming needs to be altered for a stable tune.

[fzust]

Buz is basically correct. The WOT and PT maps have to be changed to as close as possible to ideal. Then enable adaption for the long-term fuel trims to work in closed-loop mode. The WOT won't change, but it is easier to tune anyway using a dyno.

[taurus6]

So in theory, if the tune is exact, the ECU won't adapt because it has nothing to adapt to. If the tune is really close, then the ECU will adapt and cause a net effect of a slight mistune. Has anyone actually accomplished this yet?

[scottyb]

Originally Posted by taurus6

So in theory, if the tune is exact, the ECU won't adapt because it has nothing to adapt to. If the tune is really close, then the ECU will adapt and cause a net effect of a slight mistune. Has anyone actually accomplished this yet?

Closest I got was 3 weeks before tune was altered. The ecu will adapt no matter what you do because it wants a certain value for A/F when you will be in boost. If you are in Boost and the ECU doesn't want it changed then you are just too lean and will have problems.

[taurus6]

OK, that makes sense. So are you saying that during closed loop, you can get the tune close enough to prevent the ECU from adapting, but during open loop it goes way off, causing the ECU to adapt?

If so, can an output of the piggyback cause an alternate (spoofed) input to the ECU instead of the 02 sensor that only occurs at a certain boost point. I assume anything over the normal vacuum that the ECU expects normally.

[scottyb]

What I'm saying is that at times of low boost you can spoof the ECU so that it won't alter the tune. That's what you want. But unless you alter the 02 readings during time of Boost there will be no way to fool the ECU. You will not always be in Open Loop at times of Boost. Never mind that there are at least two different Open Loop conditions one that follows Predetermined Maps and one that does not.

[fzust]

The adaption is to maintain 14.7 A/F in part throttle closed-loop conditions. This adaption occurs with change in temperature, altitude, humidity whatever. This is a good thing. The Open Loop maps are offsets to the base maps based on Lamda. So if you Move from LA to Denver, the adaption will tweak the closed loop maps and then Open loop is based as an offset from that.

[trompazo]

Having the ECU ignore 02 sensor input on boost sounds like a very silly way to tune.

Why would anyone resort to all these silly things when you could get something like a stand alone ECU such as the Hydra? The Hydra already has been used on this engine in forced induction applications, can control the cams, offers Wide-band 02 AFR target mapping, water injection control, etc. The thing only costs $1500 which is likely around the same as a piggyback (Emanage/Xede etc.) and a ECU reflash combo.

Having an experienced Hydra tuner tune a turbo 2ZZ would take a few hours. Piggybacks can only do so much. Why keep trying to put a round peg in a square hole?

[Boosted2.0]

Yup - piggybacks suck. Hydra or PowerFC would be the easiest / best ways to go.

[taurus6]

I was trying to salvage what I had invested in until a reflash was available. Does the Hydra properly control the cam changeover? I was thinking I might have to go to a Haltek E6X, unless the Hydra's better.

Hell, it's only MORE money at this point.

[trompazo]

The hydra can control the cams on many applications. I use it on a Subaru STi with AVCS.

They also have applications for the Celica/matrix for it to control VVTi in closed loop. With Closed Loop, the ecu is actually monitoring cam angle and will be adjustable by entering a Target number of Crank degrees(double that of cam) and the ecu will continue adjust the duty cycle to meet the target.

[taurus6]

Is the Hydra available yet for the Elise? The website says available in July. Anyone know first hand?

[trompazo]

The one for the Celica would work fine, you would just have to figure out the wiring. I have heard they are making a plug and play harness for the Elise but it's not out yet. Tuning it would be the same as any other application, so if you knew what you are doing you could get it to work.

[trompazo]

And I also heard that the owner of Hydra USA drives an Elise, so I suspect it is in development for this application.