I love it, wish the 8 did the same, I hate disconnecting the battery all the time while rescaling a new type of injector.

 

x2 nothing more than waiting for it to cycle thru . I say the big thing is to have patience and dont get ahead of yourself. It can take from 30min to 5hrs (one guy replace his intake mainfold, the throttle was TOO tight, 1 1/2hr later realized that his tps was a little higher than normal had to start all over. Fuel trims were all over the place once I fixed the cable and TPS returned to normal not to mention is spark plugs were gone because he was driving around with 880's on stock scaling).

 

This is totally feasable if a few disam guys wanna put their heads together. Most WB's have a linear 5v output which can be setup with an ADC input. Have the fuel table work just like the ECU based boost control. It reads a value from a sensor and has a built-in correction table. Mimic boost control and create a closed loop WB fuel control. Then, we'd be able to have our fuel map set to target the EXACT AFR value's we enter in each cell since the values are directly related to the WB linear input values. This would be unbelievably kickass.

 

good idea jamie

 

Um, yes, thanks, but my name is Ted. LOL


Bingo. Essentially what you'd have is full-time closed loop operation, save for the warmup cycle or exceptions that put things into default. The question is if it can be made quick enough to work reliably. If so, it will allow one to accurately tune the entire WOT fuel table in a few minutes. Autronic uses something similar to this, but I don't know their software methodology.

 

That would be my concern. I'm sure there are ways around it with extra tables for lead-time and proactive changes similar to the way accel enrichment works, but the lag from a wideband sensor and the quickly changing AFRs during boost onset or flying through the RPM range would make implementing closed-loop WOT very tricky, to say the least.

I do agree though, it would be very nice once tuned/configured properly. That would be a major project for the disassembly/code gurus like Tephra, Bez, and John.


Eric

 

LOL you know what I mean but good for bring up the idea.

 

Yeah, the only concern is WB response time. We know that the ECU can react to value changes fast enough, since it does that from cell-to-cell in open loop now so the only limit is the WB O2 sensor right now. I totally think this is possible and from what I have read, the new VW GTI uses a full closed loop WB setup from the factory.

 

yeah ive been thinking about this for a long while, the only major problem I have is what if the WB is not calibrated properly, or goes out of calibration?

big problems

 

Very good point, ideally you'd want 2 WB's so one is for checks and balances.

 

I think turbo buicks have some aftermarket ECU's that use closed loop in boost, just like you guys are talking about.

 

So..... from what I can gather, the zeitronix WB operates at 74 samples/second (I think the Innovate LC-1 is like 12 samples/second). I know when logging thru the laptop people have seen it be much slower with multiple parameters being logged at once,but this would be a single shot into the ECU (which we could log via evoscan THRU the ecu anyways) and wouldn't have anything to slow down the sample rate. I'd think 74 samples/second wouldn't be half bad. Aren't the top end Autronic WB's used at dyno shops like 100 samples/second? I could live with 74

 

Autronic has a Autotune feature that you can completely tune the whole fuel map in closed loop. Problem is for it to work correctly you have to use the Autronic Mode B Analyzer which is something like $2K and basically becouse you should use it becouse of how fast the response time is. It works very well to get you close but you have to hold it in each individual cells for a set period of time depending on what you set the error +/- to be. The lower you set the error the longer it takes in each individual cell to work. You would definetly need a load bearing dyno to be able to get this to work the way it is meant to work. After the table is setup though you still run the ecu in open loop normally.

But Autronic supposable has a close loop timing table they are working on for the next release but pricing on certain technology just does not make this feasible at the moment.

Chris

 

Thats the one I was just referring to,lol.

 

12hz sample rate is for dataloging, LC1 also have a direct analog output and if the ECU can read voltage it would be realtime. Also I can log the LC1 with the Xede at 100 hz. At this rate the data needs to be smoothed out to be usable.