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I had a chance to go to the local track for a street legal drag racing night. Track was unprepped DA was 3700ft and my race weight was 5432lbs. 91 Octane 0 ethanol fuel.
I made a total of 16 passes using various methods of launching and drive modes some runs with a passenger and a run in 2H mode.
Without getting super technical and breaking down every single pass here are the takeaways.
My best pass of the night was
Here are the other “good” passes
I define a “good” pass as one where the vehicle shifted as it should, meaning that it shifted and kept the power going and I couldn't percieve a slow down. There is a serious issue with tuning where the vehicle pulls back the accelerator (gas) during shifts. Sometimes this happens sometimes it doesn’t. The best I could do to control this was change my launch slightly. The ideal times were 14.4-14.5 I could attribute the 14.5 “good” passes being heatsoaked which isn’t bad only losing 1 tenth due to hot lapping.
I ran in Hybrid mode for all runs except 1 where I did E-Save but there was no difference since WOT in E-Save is the same thing as WOT in Hybrid mode.
I would pull up to the staging lanes in hybrid with engine off. Once the pre stage lights were on I would go full throttle and foot on the brake so the ICE would start up and the let go of the brake once the tree dropped. This caused wheel spin and usually made the 1-2 shift really bad where the vehicle nearly stopped then started up again.
The best times I managed to get was in Hybrid mode pulling up with the ICE off then feathering the gas just far enough that that ICE would start. Once the tree dropped I let off the brake but waited about a second before I went full throttle, this still allowed me to get a 1.9 60ft but with no wheel spin and most times allowed the 1-2 shift to work without any issues.
I did a run in 2H mode which was the absolutely slowest of the night, but interestingly enough the MPH didn’t suffer that much
The following passes were in the 14.6 range and they all had the bad 1-2 shift and a slightly worse 60’ time. Most of these were the full throttle launch which caused wheel spin and caused that poor 1-2 shift.
The following were 14.7 runs
The 14.72 run had a good 1-2 2-3 shifts but it fell on its face for the 3-4 shift for some reason
The 14.79 run had a bad 1-2 shift, others were fine
The following runs were 14.9
The 2 passes with an opponent was with my friend riding along. These 2 passes were “good” without any perceived poor shifting.
The 3rd solo pass was without my friend riding along but with the bad 1-2 shifting, so I ran the same time as having an extra 200lbs with me because the shifting was bad most likely because I spun off the line as well. There is a video of this run, you can clearly see how the front end drops for a second before the vehicle starts accelerating again.
The following runs were in the 15 second range.
The 15.0 pass I did not brake torque and let it take off in electric mode and then have the ICE kick in, which was very slow, 2.4 60ft says it all.
The 15.2 pass I tried manually shifting and hit the rev limiter in each gear even though I made sure to “shift” up before getting to 5000rpm.
Here are the only other videos I got of the night
I did 16 passes last night. It was lots of fun, started with 90% battery and made my last pass with <1% battery, didn’t really make a difference as I still had the power available. I’m thinking had I started the night with no battery charge I probably would have got the turtle light at some point.
So tuning is major issue holding back more performance on the 4xe platform. I get its not supposed to be performance related but it’s still pretty bad. Here is a HP Tuners screen shot showing a “good” vs “bad pass where you can clearly see how the throttle is backed off on the 1-2 2-3 3-4 shifts on the “bad” pass but on the good pass the 1-2 shift is fine.
HP Tuners does not monitor PID's very well at all, just SAE ones and nothing vehicle specific which is what I'm used to, HP Tuners doesn't support the 4xe but also their GPEC5 PCM support on other vehicles (GPEC5 started in mid 2021 and all 2022s getting it) is a bit spotty right now. At the very least being able to monitor proper parameters might be able to better see what's going on.
There is probably more analysis I can do but I’ll leave this for now. I also have some interesting FORM stuff to post after being at the track as well.
I made a total of 16 passes using various methods of launching and drive modes some runs with a passenger and a run in 2H mode.
Without getting super technical and breaking down every single pass here are the takeaways.
- This vehicle is FAST…..off the line it can keep up with some quicker vehicles for a little bit and then it falls behind
- The PCM/TCM tuning on absolutely terrible. The vehicle basically completely gets out of the throttle during gear shifts although it doesn’t do that each time, it’s almost random in nature which makes it frustrating.
- I could pull 1.9 60’ with All terrain tires
- How you launch the vehicle directly affects how good/bad the vehicle performs.
- ESP and TC Full off vs Partial off vs Full on had ZERO effect on times
My best pass of the night was
Here are the other “good” passes
I define a “good” pass as one where the vehicle shifted as it should, meaning that it shifted and kept the power going and I couldn't percieve a slow down. There is a serious issue with tuning where the vehicle pulls back the accelerator (gas) during shifts. Sometimes this happens sometimes it doesn’t. The best I could do to control this was change my launch slightly. The ideal times were 14.4-14.5 I could attribute the 14.5 “good” passes being heatsoaked which isn’t bad only losing 1 tenth due to hot lapping.
I ran in Hybrid mode for all runs except 1 where I did E-Save but there was no difference since WOT in E-Save is the same thing as WOT in Hybrid mode.
I would pull up to the staging lanes in hybrid with engine off. Once the pre stage lights were on I would go full throttle and foot on the brake so the ICE would start up and the let go of the brake once the tree dropped. This caused wheel spin and usually made the 1-2 shift really bad where the vehicle nearly stopped then started up again.
The best times I managed to get was in Hybrid mode pulling up with the ICE off then feathering the gas just far enough that that ICE would start. Once the tree dropped I let off the brake but waited about a second before I went full throttle, this still allowed me to get a 1.9 60ft but with no wheel spin and most times allowed the 1-2 shift to work without any issues.
I did a run in 2H mode which was the absolutely slowest of the night, but interestingly enough the MPH didn’t suffer that much
The following passes were in the 14.6 range and they all had the bad 1-2 shift and a slightly worse 60’ time. Most of these were the full throttle launch which caused wheel spin and caused that poor 1-2 shift.
The following were 14.7 runs
The 14.72 run had a good 1-2 2-3 shifts but it fell on its face for the 3-4 shift for some reason
The 14.79 run had a bad 1-2 shift, others were fine
The following runs were 14.9
The 2 passes with an opponent was with my friend riding along. These 2 passes were “good” without any perceived poor shifting.
The 3rd solo pass was without my friend riding along but with the bad 1-2 shifting, so I ran the same time as having an extra 200lbs with me because the shifting was bad most likely because I spun off the line as well. There is a video of this run, you can clearly see how the front end drops for a second before the vehicle starts accelerating again.
The following runs were in the 15 second range.
The 15.0 pass I did not brake torque and let it take off in electric mode and then have the ICE kick in, which was very slow, 2.4 60ft says it all.
The 15.2 pass I tried manually shifting and hit the rev limiter in each gear even though I made sure to “shift” up before getting to 5000rpm.
Here are the only other videos I got of the night
I did 16 passes last night. It was lots of fun, started with 90% battery and made my last pass with <1% battery, didn’t really make a difference as I still had the power available. I’m thinking had I started the night with no battery charge I probably would have got the turtle light at some point.
So tuning is major issue holding back more performance on the 4xe platform. I get its not supposed to be performance related but it’s still pretty bad. Here is a HP Tuners screen shot showing a “good” vs “bad pass where you can clearly see how the throttle is backed off on the 1-2 2-3 3-4 shifts on the “bad” pass but on the good pass the 1-2 shift is fine.
HP Tuners does not monitor PID's very well at all, just SAE ones and nothing vehicle specific which is what I'm used to, HP Tuners doesn't support the 4xe but also their GPEC5 PCM support on other vehicles (GPEC5 started in mid 2021 and all 2022s getting it) is a bit spotty right now. At the very least being able to monitor proper parameters might be able to better see what's going on.
There is probably more analysis I can do but I’ll leave this for now. I also have some interesting FORM stuff to post after being at the track as well.
