Roland@pcmtec Posted January 25 Share Posted January 25 Using data from multiple sources will add considerable complexity. It's unlikely we will do anything other than a single hard coded channel until we have more staff and can implement proper user defined maths. There are so many edge cases with combining the dlp and dmrs. They poll at different intervals, what happens if the DLP gets unplugged mid logging but the pcm does not. What happens if a dlp sample is ready but the dmr sample is lagged by 2 seconds due to someone logging 200 different channels at once, so we wait and hold up the entire logger, so we simply use the last good sample etc. It would be a week long design discussion before even touching a keyboard. Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 27 Share Posted January 27 On 1/24/2024 at 1:36 PM, Roland@pcmtec said: The Gauge units are actually correct by the way. My Mustang reads 450mmHG at idle on the factory dash. Ford incorrectly use their units internally for MAP in all their vehicles. Obviously there is not positive pressure in the manifold at idle, its a partial vacuum, however Ford don't believe in negative numbers for MAP, so it is what it is. 540mmHg is 10.4 psi, -4.25 psig In the Falcon they use inHg as the default raw units for boost (IBP) and MAP. In their raw unadulterated form if you datalog these values you will see 10inHG or 5psi on the map sensor at idle, and 0 psi on the boost sensor (as its on the compressor outlet). Once on boost you will see 8psi (on a stock car) IBP and 22.7 psi on the MAP sensor. As this doesn't really make sense (but it does to Ford and still does to this day) we have since fudged the raw units of the MAP sensor to pretend that the native units are InHga, this means you'll see a negative value on your map sensor when in vacuum. Beware however that every single table in the editor that references the map sensor does not have negative numbers, so whilst it may make more sense in the datalogger, you'll now have to add 14.7psi or 101.325 kpa to any MAP referenced table (or change your datalogger units to be psia/inHGa and compare them to psi/inHG. Boost is not affected as this has always read what you see on an oldschool analog boost gauge, it also doesn't read negative due to where it is positioned. So we have just changed this so you will see -4psi at idle on the MAP sensor when selecting PSI, however if you need to reference this against a MAP referenced table (there aren't that may) you need to change the units to PSIA/inHGA. This might make you happier, but I guarantee it will confuse someone else who goes "why does my custom VE table start at 0 inHG/0kPa). You can't win here. If we get complaints or confusion about this we may change it back so that you will never see a negative MAP value. There isn't really a correct answer here and it is not possible to please everyone. Here is how your datalog will look now if you take a new one today. Just for fun, we left all the other DMRs alone in the Mustang so they match what you see on the dash and other dataloggers. MID57543 is is shared on the Mustang/Falcon. MID42519/MID02776 are not we are keeping these in the true ford spirit of "no negative numbers" with their raw native units as inHG (despite it not actually being inHG). So a negative number doesn't reflect vacuum? Quote Link to comment Share on other sites More sharing options...
Puffwagon Posted January 27 Share Posted January 27 The best way to wrap your head around it is to remember that the air pressure we walk around in is about 14.7psi. When a car idles it pulls some vacuum but not so much that it's actually in vacuum. There is still positive air pressure in the intake manifold despite the engine lowering it from atmospheric pressure. I gave up on anything map related in the logger making sense except the actual boost pressure. The rest of it I just do mental arithmetic if I need to understand it. Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 27 Share Posted January 27 8 minutes ago, Puffwagon said: The best way to wrap your head around it is to remember that the air pressure we walk around in is about 14.7psi. When a car idles it pulls some vacuum but not so much that it's actually in vacuum. There is still positive air pressure in the intake manifold despite the engine lowering it from atmospheric pressure. I gave up on anything map related in the logger making sense except the actual boost pressure. The rest of it I just do mental arithmetic if I need to understand it. Thx puff, some posts not always on here see things a bit differently, but it tends to make some sense to me Quote Link to comment Share on other sites More sharing options...
Puffwagon Posted January 27 Share Posted January 27 All good, sometimes you just gotta hear things differently and they make sense. Same outcome, different way of understanding. 1 Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted January 27 Share Posted January 27 2 hours ago, Stephe said: So a negative number doesn't reflect vacuum? A vacuum is 0. A negative pressure is impossible, a relative negative pressure however is possible. It's all because boost guages from the 90s were to show how much "extra" pressure you were getting, but when you are measuring actual pressure, no one uses negative numbers except for people who are used to seeing them. Depends what you are comparing one pressure to, atmospheric, or 0.if it's atmospheric you'll see a negative number, if it's 0.. It will always be positive. 1 Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 27 Share Posted January 27 1 hour ago, Roland@pcmtec said: A vacuum is 0. A negative pressure is impossible, a relative negative pressure however is possible. It's all because boost guages from the 90s were to show how much "extra" pressure you were getting, but when you are measuring actual pressure, no one uses negative numbers except for people who are used to seeing them. Depends what you are comparing one pressure to, atmospheric, or 0.if it's atmospheric you'll see a negative number, if it's 0.. It will always be positive. That explains it quite well, thanks Roland Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 27 Share Posted January 27 On 1/24/2024 at 1:20 PM, Roland@pcmtec said: It looks like the only issue is the checkboxes are being deselected when you re-load the layout. If you can raise a support ticket for this that may be a simple fix when people are free'd up to look at it. Once checked all of the items retain the order and chart position from the TLO file. Howdy, so I tried your suggestion and saved selected layout channels whilst connected and logging the car, sadly after closing down the logging and reloading the saved files but is still doesn't load my saved layout. Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 28 Share Posted January 28 36 minutes ago, Stephe said: Howdy, so I tried your suggestion and saved selected layout channels whilst connected and logging the car, sadly after closing down the logging and reloading the saved files but is still doesn't load my saved layout. I tried to send a ticket but it looks like it isn't working, nothing happens after clicking the submit ticket button, the screen doesn't change like it would be expected to, meaning there is no indication the ticket was submitted. One of those days..... Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted January 28 Share Posted January 28 37 minutes ago, Stephe said: I tried to send a ticket but it looks like it isn't working, nothing happens after clicking the submit ticket button, the screen doesn't change like it would be expected to, meaning there is no indication the ticket was submitted. One of those days..... Could you email it to support@pcmtec.com instead. It will auto create a ticket. We will be looking up into why the channels are not automatically ticked when loading a tlo. We recently did a devexpress UI library update which may have regressed this. Loading an off-line layout file will also be added to our test procedure for future updates. Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 28 Share Posted January 28 3 minutes ago, Roland@pcmtec said: Could you email it to support@pcmtec.com instead. It will auto create a ticket. We will be looking up into why the channels are not automatically ticked when loading a tlo. We recently did a devexpress UI library update which may have regressed this. Loading an off-line layout file will also be added to our test procedure for future updates. Shall do, thanks for your help I appreciate it Quote Link to comment Share on other sites More sharing options...
Stephe Posted January 28 Share Posted January 28 13 minutes ago, Stephe said: Shall do, thanks for your help I appreciate it Just sent email to support, cheers Quote Link to comment Share on other sites More sharing options...
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