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Messages posted by: GreenDieselEngineering
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A couple days ago we released a slight change to the EVIC calibration. The slope was reduced by about 8%. The effects vary based on driving condition. Here are the limited results we have thus far. In highway cruising the EVIC was reading about 1.5mpg high and in city driving it was reading about 1.0 mpg low, so the end result with mixed driving should be more accurate than stock.

The input for the calculation is a non dimensional fuel flow rate, then corrected with slope factor and finally divided vehicle speed. The flow flow rate is based on the injector flow maps from the factory test bench, these are not accurate at low fuel flow rates, so this messes up the overall accuracy. If the odometer is not reading the same as GPS, the accuracy will also suffer. Even with all this, we think the cal change is directionally correct for having the EVIC reflect reality and not be so biased to the high side.
The turbo is on back order at the moment. We have secured a supplier to complete all the machining work, so we are just waiting for parts. It may take up to January for kits to be available. Sorry for the delay, but once it is ready it will be worth it!
The friction modifier may be a good solution for borderline shudder problems. We noticed that the product comes in a 2 oz tube, did you only need one tube or are several required to acheive the desired effects? Does this mean you are sticking with the HOT tune on the one vehicle?
Good question. It appears to be more pronounced with the hot tune. The rate of decreasing the fuel when releasing the pedal is the same for both tunes, but the hot tune allows 15-20 % more fuel in high load driving. So with the hot tune the decrease to zero fueling takes slightly longer and there is a noticeable difference.

We have spent the last few days working on optimizing the fueling ramping rates based on throttle input. The results are very promising as we have still been able to keep the "clunk" down to a minimum and the vehicle does not feel like there is any surging or positive torque when tipping out of the pedal. This part of the tune is very subjective to feel and 10 differenct customers may have 10 different preferences. The goal is to find the proper balance where no one even notices it...if it is transparent then we did a good job.
The tunes have changed the pedal response significantly. One of the areas we focused on was to minimize the "clunk" in the driveline due to torsional lash wind-up. In order to do this we added filtering to the pedal, which tends to make the response more smooth, but slightly slower.

We would like to get a better understanding of your driving preferences for pedal response (snappy vs. smooth) and the relative importance of driveline clunk...does it matter? Several customers have noted the increased "coasting" with the tune, however, this may be a hinderence for some drivers. This part of the tune can be revisited and it should not effect fuel economy.

This is a democracy so vote early and often! We look forward to hearing your suggestions.

This is true, regardless of the firmware in the ECU. Both our tunes will have the latest glow plug calibration installed. This at least makes sure your vehicle is up to date in terms of glow plug service releases. We updated all our cals on 20 October.
There are no issues if one unplugs the glow plugs, other than the constant CEL. We could turn off the glow plug CEL if customers really wanted it. Down in Texas where you are at, the glow plugs are not used that often and most likely they will not be fully powered in order to acheive the regulating temperature. The northern portion of the US and Canada tend to put the glow plugs through more exercise and would have a higher percentage of failures. Having the latest calibration of the glow plugs is the most important factor as it works to reduce the maximum plug temperature and increase life.

If you had a cold snap in Texas and the ambient dropped down to 15-25 F overnight, the CRD would be very hard pressed to start without the glow plugs operational, unless the block heater was plugged in all night. After starting, the engine may have some misfire for the first 2-3 minutes without glow plugs working. You may want to test this on your vehicle a few cold mornings to see the effects in your region.

It would be interesting to know how many owners have actually had a glow plug issue and what region of the US they are located.
We tried to adjust the curve that controls the instantaneous fuel economy, but there are several inaccuracies in the lower end of the fueling curve. With the GDE tune less fuel is used and it operates more at the lower end of the inaccurate fueling curve, thus making the EVIC read slightly higher fuel economy. The software is very limited here.
The Body Controller is a separate computer from the engine contoller and that TSB will have no effect to the tune. We are going to take more measurements in the coming days and then look into the TSB stutus on our 06 vehicle. Minimizing the leakage rate will only extend battery life.
The TCU uses several different signals together to determine the shift points.

Vehicle speed does not seem to be a critical factor, at least changing the revs/mi in the cluster did not have any effects. There are other internal checks in the TCM that are limiting the shift points.
Yesterday after driving our 06 with new red top, the voltage after shutdown was 12.8 V (warm battery). This morning the voltage (with key off) read 12.3 V. The readings vary wildly depending on the conditions.

We also measured the current draw inherent with the vehicles after sitting overnight. Both the 05 and 06 measured almost 1.7 amps of current across the terminals, not sure how this compares with other vehicles yet. Most vehicles have some sort of leak rate for current, usually low enough to be able to start the vehicle after a few weeks of sitting (in a perfect world).
It is a 150k factor converter based on our information. Not sure what that equates for the stall speed, but it is the same as production.
We have successfully translated the glow calibration from the latest release and installed it on all the tunes we offer. With this, no matter what ECU part number one has, with the tune the glow plugs will be operating at the safest temperature (as best as it can be). This will help to ease worrys about glow plugs for customers with older vehicles looking for an update.

We did our best to prevent shudder initiation with the ECO tune by limiting the amount of torque available between 1650-2100 rpm. We were not able to get shudder even when pulling a trailer, the transmission would hit the 'unlock' region before the shudder started. This was accomplished with the F37 traditional damper converter. The ECO tune has not eliminated all shudder in every customers vehicle. There is just too much variability in the amount of torque the stock converter can safely handle and if you already have shudder the ECO tune will most likely still produce enough torque to cause shudder, there is no fix for a weak TC. The HOT tune and turbo kit both cause massive amounts of shudder with stock converters...this is the main reason we opted to update both our vehicles with the new Mopar unit.

It might be nice to experiment with different k-factors, but the Mopar unit is not very far off base, as the stall speed changes so does the multiplication factor. The k-factor is a trade off for fuel economy (less slip) in light load driving and having the rpm in the best band during heavy load driving. Keep in mind, the new Mopar unit is used on all the new Jeep diesel products sold overseas and these engines have more power. The best part of the new converter is the higher spring capacity in the lock-up clutch as this is the problem source with the current TC in the KJ. We understand your concern and it is rightly based, but the new TC is a big step in the right direction.

Best of luck!

We measured the voltage during the first second of "key-on" before starting a cold engine. There is some draw from the glow plugs during this period. Today with the new optima red top we measured 11.2 V and the engine started in 1.35 seconds. The battery voltage seemed to have a strong positive effect.

12.1 V is not a bad number with no loads, try measuring it with a load from the glow plugs in the morning. A failing battery will have a larger voltage drop, ours was down in the 10s V.

We trickle charged it for 10 hours and measured voltages around 11.7 V, then after three days of sitting the voltage would drop to about 10.7 V.

Here is a rundown on the 06 with new battery voltage measured at the terminals from this evening after sitting all day at 55 F.

key off 12.17 V
key on 11.75 V during glow phase, steadies out after several seconds at 12.05 V
cranking 9.70 V lowest visibly seen on hand held meter
running 14.30 V
shutdown 12.50 V trickled down to 12.2 V after 30 seconds

Colder temps will drop all these numbers. We have seen cranking voltages drop down in the 7s at -15 F.

The optima has very high power density. A good battery for this application. It would be interesting to know how many people with failed batteries ever charged their battery for any reason? The gel batteries require a specific charger designed to charge in a specific manner to promote battery life. We only have a regular/deep cell charger and have a feeling this contributed to the demise of the battery. Time to go shopping for a new charger...
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