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Converting from the stock plunger TPS to a Mustang rotating type
I know that the stock plunger only gets a portion of the throttle position. For comparison, I would already be displaying 100% when using the stock sensor when cruising, and now only display around 12-15%
Megasquirt uses TPSdot but because the scales are so far off, what would be the best way to create a new one that takes into account the full sweep of the throttle body?
This is what I am using right now, I have yet to tune the potion for lifting off the throttle.
I have, but values of 218 and 735 on the stock one that does a small range gives different TPSdot readings then one that see full travel and the same spread of value.
What I am looking for is either has anyone else done a conversion to a full travel sensor, and has an Accel TPSdot Curve to share to start with, or a way to convert Aaroncakes
That is what I am asking about. The default values that Aaroncake gave worked really well for that initial 12% of travel, and then the plunger type did nothing to read throttle position past that, there was no fuel added after that. But TPSdot for 12-15 percent of travel is different then TPSdot for a full range sensor
if you have the plunger, that goes from 0-5v in a second, that same movement is only 0-1.4v on the full range.
The values I posted above are my current full range that I am using for free revving response.
Again, what I am asking is has anyone else done a conversion and what values are you running or the math required to convert the plunger values into a full range sensor values.
Seems like a lot of effort. You only really need acceleration enrichment in the first third or so of throttle opening, which is why Mazda did it that way.
It took a lot of screwing around with the TPS-WOT curve to properly mimic the Mazda sensor on my Holley setup with full-range TPS. Without doing that, your choices were having a tip in stumble at low RPM or a bog when going to WOT from part throttle. What I ended up with was a minimal amount of acceleration enrichment but a very shallow TPS-WOT curve. The problem with doing it this way is the way the system seems to work, it alters the TPSdot figure BEFORE it goes into any algorithms. I had to raise the minimum TPSdot significantly because the lower the TPS-WOT figure, the more noise it was picking up. Thus all the screwing around, trying to find a happy medium between good response and no noise.
Clicking the "..." boxes in the upper corner of each of those screens opens up the fields that lets people copy and paste the exact numbers to theirs.
Another issue is that MS3 does not use raw MS worth of fuel values like yours does, it does not need to be redone if you change fuel injector size.
I am guessing no one is using the MS3 one though, that does both accel and decel to have it pull fuel when lifting off for response and to avoid rich spikes?
My actual numbers will be somewhat worthless for you since I have 4 42mm throttle plates and the response is a bit different than the stock type throttle body. It is also a bridge port running speed density, so that there also changes the requirements a lot. The curves shown are merely for examples.
