pizote
Sun, August 8th, 2021, 08:53 PM
Got my reflash kit yesterday - put it in and uploaded the files to PH.
A couple of questions:
Are the work arounds for the CAN bus chatter still required? GPS, ABC, Transmission, etc...
Have you put your RE300 on a dyno yet to see the torque curves on each level setting?
If not, do you have calculated torque levels for each level setting?
I am going on a trip in a couple of days to get a baseline for EGT and times start times and going up grades. It will be interesting to see the difference after the repower.
1189
Power Hungry
Mon, August 9th, 2021, 11:31 AM
Chris,
We have not yet put our bus on the dyno, so all power estimations are based off of the vehicle weight versus the 0-60 acceleration times. This actually seems to be reasonably accurate and works well enough to provide an estimated power output.
On these turbo diesels, the torque curves historically are about 2.15 x HP. So a 250 HP rated calibration will generally make about 540 Ft. Lbs of torque. It will vary slightly depending whether it's a V8 or I6, as the 6 cylinder will tend to produce more torque for the same HP output than a V8. However, these numbers are going to be really close.
With my RE300 turned up, the 0-60 times indicated approximately 450 HP at the flywheel which translates into about 975 Ft. Lbs. Over the next couple days we'll be doing some on-road testing to get some mileage numbers as well as approximate HP numbers for each of the levels based on acceleration times. This will help provide a better idea of what people will be running.
Another thing to consider is that these more aggressive numbers are found with using the 2-Box systems found in 2004 to 2007 applications due to the separate IDM and the Spool Valve style injectors. The 1998 to 2003 applications running the CEC single-box setup will not be able to realize the same high output gains found in the later versions, being limited by the earlier Poppet Valve style HEUI injectors. The earlier applications are going to be ultimately limited to a maximum increase of about 100 HP on the DT466 and 80 HP on the T444e, at least for stock injectors. Modified injectors can obviously change those numbers.
As a final though on performance, the calibrations we provide (especially for the 2-box systems) will be created based on the transmission application. A 1000, 2000, or 2500 Allison does not have the same torque capacity as the 3000, and therefore we have to derate the tunes a little to keep things in a more appropriate power range. Power is nice, but at the end of the day we want to make sure that we're doing everything we can to maintain the reliability of the vehicle.
As to the communications stuff... There does not seem to be a feasible way to resolve the comm chatter on the J1708/J1587 bus. In referring to Navistar's NavKal and ServiceMaxx software, they specifically require the removal of the fuses for ABS, TCM, GPS, and other modules when initiating a reflash session. It's my assumption that if Navistar can't eliminate the issues with their tools, then I'm not going to have much success either. That doesn't mean I'm going to stop working to resolve it, but at this point in time the only method we have to ensure reliable communications is to pull the fuses.
Now, if you have an Allison with a manual shift lever (1000, 2000, etc.), these don't have the same communications and you wouldn't need to pull the fuse for the transmission. You will, however, still need to pull the ABS fuse to get it to quiet down.
I hope this is helpful. Let me know if you have any other questions.
Take care. :thumbsup: