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Why is it that the car exceeds the torque output of driver demand during WOT? Also on the flip side, if we modify the vehicle for more power output and never touch the DD table, is it a limit?
EDIT: Nevermind. From what I just read it's just a pedal feel table @ part throttle. :X What I'm specifically looking to do is have a tune that limits power under 4000RPM. I guess I'll try something else.
correct Ive never found nor had any reason to change it. whether it makes 400hp or 800hp the I prefer the part throttle be identical to stick prevents any issues from ever becoming possible such as too much tq in the rain etc...
Quote:
Originally Posted by blackbolt22
You can achieve that using driver demand. But to do so, you have to disable the WOT pedal pos start/end. Those settings force the throttle to WOT as they become active, regardless of DD. Most people use those settings as a crutch to make up for DD/ TQ tables not being well tuned.
Thanks for the replies. I also tried setting ETC Max to a lower torque but the limit seemed to not be active at WOT either...
I have some more ideas to try but welcome other ideas. What i'm trying to do specifically is limit tire shock off the line so I don't have to use traction control. When I use TC, the car fluctuates power wildly which causes knock and so 2nd gear suffers due to KR recovery.... Yes I need better tires too :D
I never leave my Driver Demand stock because it always results in throttle angle errors and loss of power. Once Engine Brake Torque is higher than ETC Request. I have Driver Demand Torque Ratio disabled in my file. I returned it back to stock to show an example.
Attachment 87538
#44355 Max throttle angle v/s rpm if your strategy has it.
Quote:
Originally Posted by Thatwhite5.0
I have Throttle angle errors at certain loads (in white) For me, EBT is higher than ETC request. Since Driver Demand isn't active @ WOT and the car is putting out more than expected, there is no harm here right?
Attachment 87550
This was my next idea after I had posted. I tested this and it had no effect at all @ WOT. The angle was supposed to be 40* and ended up being 82*. I guess I'd need to disable the WOT pedal settings like CCS86 mentionedQuote:
Originally Posted by MRRPMBRP
Quote:
Originally Posted by Thatwhite5.0
It could also just be inaccuracy in your TQ / Inverse tables causing the issues with the throttle shutting. Especially the Inverse tables seem to be a main link between the DD table and the ETC opening.
A simplified version of this flow in my experience:
[Driver Demand] = Torque Required
[TQ Inverse] = Load required for TQ Request
[Throttle Body Tables] = ETC Opening to achieve load
- Driver Demand is global, so if you always have an issue at a certain pedal position / RPM combo, that might be it.
- Throttle body tables are fairly global, so if the issue is always at a certain ETC Vacuum / ETC Effective Area / ETC angle, that could be the cause.
- Inverse tables are MP specific, so if your issue seems to coincide with weighting a certain MP, your issue could be here.
Are you saying that Driver Demand should be disabled in the Fuel Cut (set to 0) and Spark Only (set to 1) Torque Ratio tables?Quote:
Originally Posted by Thatwhite5.0
I never do that and do not recommend to anyone.Quote:
Originally Posted by metroplex
Quote:
Originally Posted by veeefour
What values do you run in your Torque Ratio tables for Driver Demand?
I feel like there is inconsistency in how these tables are described in the editor software, vs HPT employees on the forum, vs LaSota's book.
I'm going to have to agree. I think the spark ratios tables are clear but the fuel one is just confusing.
From another thread regarding [FUEL CUT] https://forum.hptuners.com/showthrea...-Torque-Ratio:
By this explanation .25 gives ability to reduce 75% of the torque via fuel cut. 1 = eliminates fuel cut, 0% of torque can be reduced.Quote:
Originally Posted by Eric@HPTuners
Description in HPT software:
Quote:
A value of 1.0 means that up to 100% torque can be reduced via fuel cut, .5 means that 50% of torque can be reduced via fuel cut.
By this explanation .25 means 25% of torque can be reduced via fuel cut. 1 = 100% torque can be reduced.
These two contradict each other! :banghead:
Oh and another thing the editor says is any value above the fuel cut ratio uses enleanment instead... Sorry but to me it seems 1.0 is the best bet.. I don't like any words that have 'lean' in them LOL. :)
You can disable fuel torque reductions like many do and it will work just fine. Disabling spark torque reductions takes the torque model out of equation "entirely".Quote:
Originally Posted by CCS86
If you spark source says "torque control" and your torque source says "driver demand" it means you are using spark torque reductions.
I advise against disabling spark TR and leaving the engine on it's own - I would only do that for test purposes.
Fuel TR can be disabled to make this easier but take a look at stock boosted applications like Roush - it's still ON.
There are many parameters with wrong description in ford calibrations - trust but verify.
https://forum.hptuners.com/showthrea...ght=enleanment
Post #6 by Steven was the best info on torque ratio and how those tables work.
That's a lot of info to digest, still have to reread it a few times because it doesn't make sense outright.
I read through this before and also the editor now says the same thing. This must mean Eric's post was incorrect for Fuel Cut but correct for Spark Cut and probably what he was thinking of.Quote:
Originally Posted by murfie
This re-affirms what I said earlier about keeping the fuel cut torque ratio at 1.00 . If you zero out the table as some suggest, you can only get enleanment. Until someone explains that enleanment isn't dangerous, I would rather a straight up fuel cut.
From Steve's post, this is what I interpreted
On the Spark torque ratio tables, if you go above that torque ratio, then spark is cut. Below the torque ratio, fuel is cut.
If the fuel cut table value is 1, then only the Injectors cut out and the ECU doesn't use enleanment.
It seems most EcoBoost and modern Fords have the entire fuel cut table set to 1, which means only the injectors are cut-out for fuel cut.
My interpretation is a little different.... Here's my example.Quote:
Originally Posted by metroplex
-Cruise Control Settings-
Spark Only Torque Ratio = 0.68
Spark Torque Ratio Limit = 0.72
Fuel Cut Torque Ratio = 0.95
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Let's say a request comes in for 50% of the torque output during cruise control, to reduce vehicle speed (maybe going downhill):
The request is 50% which means both spark and fuel will be cut. It will cut up to 28% via spark due to the clip and the other 22% (or more if spark reductions wasn't enough) will be via enleanment (very little) and mostly fuel injector cuts.
Its not so much of how much it can reduce torque via one method or a combination of methods. the ECU has ultimate control with DBW and if it determines the engine needs 100% torque reduction it will bring the engine all the way down to an idle and the pedal will do nothing. Its more of when it can use it or not and to give a preferred order. The requestor these tables are comparing to is a ratio of current or desired brake torque(Engine brake torque) over torque at indicated conditions (near 100% torque production for the engine load). So its really dependent on how detonation limited you are, what kind of baro and intake temps you are in, what your lambda is, just as everything else in torque control is. Getting to over a 1.0 torque ratio is very rare out side of low loads unless you calibrated in a specific way. At low loads enleanment is perfectly safe, but at low loads torque reduction request out side of driver demand torque are rare and the torque source used at these conditions are set up how most would want them from OEM. Popping on decel is something some want and you do need to change the ratio to achieve. It would also be very hard to get a very low ratio as you would need to be very detonation limited, some other reason to have low spark advance, have very poor fuel control, or be at a high altitude with high IATs.
Most sources are setup to see spark torque reduction and throttle torque reduction before you would get to any fuel reduction or cut. Fuel could always be an option, but again super rare nearly impossible for it to determine that out side of a strange calibration. Throttle is usually over kill as a torque reduction as at that point it becomes more of a control and safety thing for the ECU than a get the car from A to B as fast as the driver is demanding. In auto transmissions you can get other interventions like unlocking the TCC and upshifting.
I don't think we have the appropriate tables to optimize any traction control logic, and I don't know if we ever could get those tables. I use the word optimize in the most optimistic sense, as it wouldn't be an easy thing to calibrate and get any benefit from. You are better off eliminating torque reductions, and sticking to spark/cam tuning, suspension/ tire upgrades, and just controlling the traction with your foot when necessary.