Is this with a rescaled t-MAP or just installing a new t-MAP and fudging?
Is this with a rescaled t-MAP or just installing a new t-MAP and fudging?
Installing the new sensors and fudging as already stated. So could be done with anyone's software
Car is running just like it did before the sensors were put in but will leave this up to bugsy to test.
So far the issues are more to do with this MAP sensors limits and not the tune!
Due to the lack of response , we have had to go along the line of fudging.Originally Posted by IH8TOADS
We would have preferred the rescaled t-map but who knows how long that could take before becoming available.
Bugger.
Yeah mate I agree.
Wish we had access to the map sensor programming so that it could be done and finalized.
From what I am hearing captain PEG is buried at sea
With closed loop boost control tested up to 32psi, all load tables, commanded fuel and just about everything else working like factory then I am pretty happy.
Issues:
- DFCO due to the sensor range and not the tune (and this will happen even if we could do the proper scaling of both sensors)
- Having to translate the MAP reading (do this in the scanner PID).
- I am checking with HP Tuners about a table values and its limits. Bill thinks it might be a PCM issue like on GM but have asked him to check.
- Sensors that will work well. Due to (3) the best sensor is the Bosch 3 Bar sensor, it should work at least as well as factory maybe better. Next is the Bosch 4 Bar. The 3.5 bar is not so good! If 3 can be resolved then they will all be good.
So if you could live with only 30psi of boost then the Bosch 3 Bar sensor is the go. Might just even order one and they are cheap at $30US for the t-MAP. Just got to get my boost up past 21psi up top!
As Shannon says it is a work around until HP Tuners can resolve the issue (previously been aligned with the release on the non beta version of 2.25). We all agree that editing the MAP sensor scaling would be the best option and a real win for HP Tuners but at lease we have something to work with.
Shannon is still testing and am sure he will update us.
I would guess it is a better solution than what most people are doing when their boost goes past the MAP sensor limit, at least now we have full control up to about 45psi of boost!
Why is the 3.5bar not so good?
Because of the table issue the smaller the t-MAP offset the better.
bugsy is working on DFCO, might be able to get it to work but it is due to the sensor struggling to read down below 30kpa. It is pegged the other way
I have done some maths a while back and didn't think it would be a problem on stock cams...would have to go back and have a look.
Also at the boost pressure you're talking about...why worry about DFCO. Disable DFCO and cool your valves in my opinion.
Also forgive me if I'm reading this incorrectly Darryl but the sensor range given by Bosch does not control what the PCM measures to or outputs. For example the stock sensor reads to 4.65v (250kPa) which would imply a 73.825 inHg max reading. However my logs show a max of 76.xx inHg so based on the factory slope of 15.98 and offset of -0.49, the PCM is reading to 4.8 volts. The same could be implied for the other end of the sensors range. 0.3v with a 3.5 bat t-MAP should have a true gauge reading of approx -25.6 inHG....easy as on stock cams.
Toads,
From my calculations the PCM does have a limit of what I think is 4.75V but you may be correct. These limits pop up in quite a few Ford PCMs and are mainly around the MAF voltage so I just guessed it was the same limit for the MAP sensor. When you calculate 4.75V you can see why we get pegging at 255kpa. The other end of the scale could be a Ford PCM issue but I doubt it as I have seen 0.0V on my O2 sensor. As we are not seeing readings much below 0.3V, and this is outside the sensor range anyway (I think Bosch has a P1 voltage of 0.5V and their P1s tend to be 0.4 and above), I think we may have hit the bottom line of the sensor as shown on the Bosch datasheets.
Should have added that the sensors range is not the p1 and p2, that is the range they say is linear. It does read outside these values and that is why we can get it to idle as I think idle is around 0.3V.
Last edited by DarrylC; 08-10-2015 at 09:53 PM.
The problem with a fudging is what Darryl maybe experiencing now, in that you may get into negative offset values for the speed density equation....which the PCM won't accept.
If you use the slope and offset for both a 2.5bar and 3.5bar t-MAP and get absolute pressure values for all voltages...and then plot them against each other you will end up with a perfect linear equation of y = 0.7216x - 3.1499. (The inverse equation for voltage is y = 1.3859x + 0.2614. Where y is voltage and x is map).
You can then use this to recalculate slope and offset values for the speed density tables. By doing this the calculated load value remains unchanged, which has obvious benefits. But recalculation the offset for a fudged sensor will bring you into negative offset values (at low RPM) which the software can't deal with. I'm assuming this is what you're seeing Darryl?
Fudging isn't that hard to make the system work....however at peak VE for example on a pegged sensor you would normally just lower the injector high slope to get the fuel you need....with a 3.5 bar sensor you need to actually use a re-calibrated speed density slope and offset which is then further 'fudged' due to the fact that the t-MAP hasn't been recalibrated. It starts turning into a massive saga ending in 'where is that Haltech'!?
Toads after this:
I sent you all the information to work it out so was a bit surprised by this especially after your comment about Jet:
Yes you are onto it but missed an important point that there are no real issues and the tricky bit is working out what to do with these points and if they will be hit. The problem is not as you say at low RPM at all. And the way around it is to understand the SD side enough to work out what will be the actual result.
Surprising what we are seeing is not the recalc at all it is because of the sensor itself.
Anyway anyone who scales their injectors to get the fuel flow up top off the MAP sensor is doing themselves as serious disservice in normal driving. What I have done gives full control of the tune.
Last edited by DarrylC; 08-11-2015 at 02:28 AM.
What have you sent me? I have NFI what you are on about lol.
More than happy to put up the PM I sent you and your replies if you really do have NFI lol
If you don't mind, would save me looking.
Glad to oblige. Your PM to me at 11:53 AM today from the original PM I sent you at 10:26. Check out the bold bits
email REMOVEDHACH3CAI'll have a look in SCT. Also what model / strategy is your car?Brendan, if you still have access to SCT and if you wouldn't mind would it be possible to check what the minimum value for their equivalent of "Map at Zero Airmass" is? HP Tuners is zero but I am hoping SCT can go lower
Probably enough for someone like you to work out what I did
I still cant believe how simple it was and how effective it is. Shannon says the car drives like factory but has full control up to the limit of the map sensor (~45psi boost). He has tested closed loop boost control up to about 32psi up top which I think might be getting into his turbos limit (GTX).
Shannon also reported we have linear readings from the sensor from about 15KpA indicated (actual about 33KpA). My car idles at about 25 but not in gear so 4 bar is a good compromise. 3 bar would be perfect but I am thinking of adding a couple of supplementary LPG injectors so may be able to get beyond my 16psi limit up top.
One day I would love to know what SCT puts in for the Bosch 0 280 158 017 injectors as I can get these injectors (@70psi) real close to the LPG flow but I have issues on decel, rich on Petrol, lean on LPG and am sort of over worrying given I have fuel tims around +/- 1 on both fuels.
Thanks in advance.
Regards, Darryl.
Easier to get me on that.
Also note that if you run closed loop on an FG....there is a ton of boost related tables that HPT has not got access too. BF doesn't have this issue.
I have NFI but I believe you!!
Roger.
http://www.fordforums.com.au/showthr...1329587&page=2
Get hold of some of the guys in this thread......this was heavily discussed many moons ago and escalated from here amongst some of us.
Coming across as quite Petty there Darryl given the amount of info toads has freely given out over the years. I also have nfi what you are upset about.
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