Well, I did a thing.
- Thread starter Jonohhh
- Start date
86X
True Classic
Oh sorry I should have been more descriptive. The 2ZZ is in my Exige. It is supercharged vs the 500 turbo. If I did an engin swap in the X right now my wife would have my head at the end of a spear in the front yard. I am waiting till next year to decide what I will do with the X. I just finished the Exige and now am just fine tuning my VE Tables. But before I was done I had a problem with a cam sensor. My wife had to pull it and me home. Someone was not happy. So now I am on a short leash.
Jonohhh
True Classic
I haven't been around much, since I am now back at school, but I figured id stop by to give some updates.
The Abarth is running really well nowadays. I am finally getting the tune dialed in, and I gotta say, hearing the FIRE engine at 7500rpm has given me a new perspective on it. I have pushed the boost as high as 20lbs - far from the nearly 30 it was at before, but I am taking it easy as knock control is crucial for such high cylinder pressures. Despite having setup a seemingly pretty decent knock detection strategy in the ecu, I do not have an OEM level of confidence in it.
As such, before pushing the engine further, I am going to explore options to implement ion sensing knock detection - a process which uses special ignition coils and some light processing as a means to determine cylinder pressures (in real time) simply by applying a voltage across a standard spark plug. We'll see how far I get with that process, but it would be quite cool if I can get it working reliably.
The Abarth is running really well nowadays. I am finally getting the tune dialed in, and I gotta say, hearing the FIRE engine at 7500rpm has given me a new perspective on it. I have pushed the boost as high as 20lbs - far from the nearly 30 it was at before, but I am taking it easy as knock control is crucial for such high cylinder pressures. Despite having setup a seemingly pretty decent knock detection strategy in the ecu, I do not have an OEM level of confidence in it.
As such, before pushing the engine further, I am going to explore options to implement ion sensing knock detection - a process which uses special ignition coils and some light processing as a means to determine cylinder pressures (in real time) simply by applying a voltage across a standard spark plug. We'll see how far I get with that process, but it would be quite cool if I can get it working reliably.
86X
True Classic
Will you be pinning that knock sensor into the EMU?
kmead
Old enough to know better
This is akin to Saab’s Trionic system I presume?
Jonohhh
True Classic
Precisely the concept and perhaps even the implementation.
Ionic knock sensing has been used in engine development for quite some time now, and is a proven method... But I'm on the fence about what strategy to go with.
My current plan, if I can't get my hands on Delphis ion sense coils and their OEM documentation, is to use the Saab system and fool my EMU Black into thinking it's a knock sensor signal, using a a dev board that inputs the "knock present" pulses from the SAAB CDM, and produces a set frequency output (that the ECU is looking for) and varies the amplitude based on the number of pulses received in a given window. I am hoping that, given the lower noise of this signal, the Saab CDM will listen to the FIRE 1.4Ts knock frequency of around 8.85kHz.
I'd much rather just send the ECU 0-5v for a knock severity signal, but when I asked if this was possible (and gave the context of ion sensing), the CEO of their USA branch said "I can't fathom why you'd want to do that."
I wanted to tell him to fathom harder, but instead just told him why ion sensing is better in a number of ways for a decent number of "noisy" engines, given the shortcomings of their detection system. No response...go figure.
Dr.Jeff
True Classic
Just about the time COVID hit there were a couple of companies developing ionic knock sensing systems for the aftermarket. The hope was to produce some sort of fairly universal system that could be tuned to use on many different applications. However at that time they only had preliminary designs more directed at common engines (e.g. the GM LS), and they were incredibly expensive. Due to COVID their progress was delayed and the trade shows that included those companies were put on hold. So I do not know what the current status is for it. Hopefully the upcoming show season will be more 'normal' and I may see some of the latest developments with this technology.
Jonohhh
True Classic
That would be really, really neat. I didn't realize there were companies trying to bring it to the aftermarket already.
I fear, like you suggest, that it'll be prohibitively expensive. I think I determined I could make a working system myself for around $450 including the ignition coils. While I don't have that money at the moment, that is significantly cheaper than I imagine an off the shelf product will be.
I'm going to talk to our engines development professor here at school and ask if I'm being a moron by even trying this myself. I probably am, we'll see.
Jonohhh
True Classic
After a frankly absurd amount of time getting the fueling and acoustic knock detection dialed in well, I've finally turned up the boost a bit. There's still more power to get from it at this boost level, purely due to ignition timing, but I figure I'd share.
At some point soon I'll post the datalog from that pull for those that were curious.
At some point soon I'll post the datalog from that pull for those that were curious.