I’ve got a running car with a GM LT1 engine and an ECUM EMU Pro 8. I’ve implemented the documented CAN interface from CANTCU, and the EMU Pro sees it just fine.
The CANTCU sees all the engine data it has requested as well (rpm, throttle position, MAP, etc. etc.).
Looking at what the CANTCU is requesting seems to boil down to a “cut %”, which I assume a ignition cut, and a “blip %”, which I assume means a throttle blip.
Given all that, can anybody provide some guidance about how I go about doing that? The CANTCU wiki has no useful information, and I don’t quite see how to do it from within ECUM Pro software.
I’ve found a “Custom” ignition cut table, and I’ve put some preliminary values there. X axis is CANTCU_Cut%, with values ranging from 0 to 20 degrees corresponding to the 0 to 100% cut request coming from the trans controller. I’m not seeing anything similar for throttle blipping though…
Thanks for that link. I’ve got a running car now with the Pro/LT1/HP70 combination. I am having some trouble with the CANTCU going into Limp Mode with code 420231 / 420331 / 420431. Is there anybody out there that might know how to investigate these codes?
I’m back in the shop – I need to get this car delivered. CANTCU tech support tells me that I’m transmitting a torque of zero and that’s why the shifting is failing as the TCU is using that value for shifting and the clutches are slipping, leading to limp mode. Can anybody provide a guide on how to transmit torque from the EMU Pro?
Ah, if only. I introduced that error when uploading to the forum. The ECU has “Base”.
I did just notice that the EMU is sending data as signed 16 bit, and the TCU is expecting unsigned data. The car will be back here in my shop any minute. That will be the first thing to change.
The xml file you posted is a CANx file. You can import that file in the project tree instead of manually adding the channels. Also it does show unsigned 16bit channels.
Right. That’s exactly how I set this up originally. The issue there is that there’s an error in the CANx file. The third parameter doesn’t exist in the EMU Pro8 list of variables. So I fixed that, and somehow made the interface signed instead of unsigned. But even after fixing that, the TCU sees 0 torque. I need to figure out how to see transmitted CAN data in the log.
Correct the base tq table needs data entered for the engine. Also note the tq channels like ‘engine’ or ‘base’ are different. Base being only the table, whereas other channels show loss from things like the AC, alternator etc… Also note that the ‘base’ channel doesn’t change when a cut is active - it only shows where load and rpm are at on the table and transmits it.
The ignition angle correction is the amount of tq the correction ign advance will have on the base table value. Then this value is transmitted using the ‘correction’ streams for tq.
The base table is your ‘goal’ let’s say and the corrections are how it affects the base table. The short answer is there is no shortcut here. You’ll need a dyno to get real world tq values for the base table. Then start bringing in your corrections to get engine braking, ignition advance tq and losses right so the transmitted tq value is correct.
Also note there is a limit ign advance variable for both + & - advance in ignition.
Thanks verey much for the detailed explanation. So even though the table is called “ignition angle”, the values in the table are torque percentage. That makes sense and explains the large values.
I hear you about using a dyno to gather this data, and it’s something I can do. I am a bit disappointed since I’m using the provided ECUMaster’s GM LT1 base configuration on a bone stock GM LT1. I would hope this information exists somewhere in ECUMaster’s files and maybe can be provided??
Data +/- 10% would be quite helpful for the short term until I can get the car together enough to spend a day on the dyno.
