The failsafes, in this case, are the ones that open the HV battery's contactors if there is any fault detected. Exceeding the engine's RPM parameters doesn't result in electrocution or a probable fire...
The failsafes, in this case, are the ones that open the HV battery's contactors if there is any fault detected. Exceeding the engine's RPM parameters doesn't result in electrocution or a probable fire...
Knurled wrote: The failsafes, in this case, are the ones that open the HV battery's contactors if there is any fault detected. Exceeding the engine's RPM parameters doesn't result in electrocution or a probable fire...
Have you ever heard of a money shift? Excessive RPMs absolutely can cause catastrophic failure of the engine or transmission. I assure you that one can start a fire by spraying hot oil onto a header or slicing a fuel line with shrapnel far easier than one can cause a high voltage fault on an OEM high voltage system (with only a software change) that is so extreme that it should have opened the contactors but did not. That sort of system failure and resulting safety concern would take multiple failure modes stacked up on top of each other.
Furthermore, if a few crazies thought that deleting safety measures from the PCM was going to give them a trophy, there is absolutely no way that SCCA could determine the PCM had been modified. You can't just swap ECUs on new cars, and there's no way a layman could sniff out the right messages on a CAN bus to see what's going on. This rule only keeps the safe and honest people safe and honest.
Like I said, I'm an engineer. An automotive engineer with a powertrain degree who has worked on high voltage system design, including safety systems. Electricity can be dangerous, just like gasoline and nitrous and alcohol and all sorts of other fantastic stuff racers have learned to love. A couple of 1s and 0s in an ECU floating on a CAN bus aren't what makes an EV safe. Dozens of engineers spend years of their lives on every single EV design executed just on the safety protocols, and somebody removing a torque limiter or derate message on its way to the motor controller certainly can't screw up high voltage safety as easily as you seem to think. Having a major collision is far more likely and would be far more likely to result in a catastrophic failure that resulted in a safety concern as well.
In the future, all forms of motor racing will incorporate increasing levels of electrification. The performance benefits are too obvious to ignore. One can choose to get on board and figure out how to handle the change and make the best of it, or one can choose to do things the way they've always been done until they're irrelevant (or so irrelevant that they become really, really hip). Seems that not giving EVs a level playing field with ICE cars puts SCCA on a bad track if we look to where things are going in the future.
If somebody wanted to review the SCCA rules and practices to ensure safety remains consistent with EVs at events, I'd be glad to work with them to make recommendations. Between FIA, SAE student racing, NEDRA/NHRA, Pikes Peak, etc. there are plenty of reference points.
Bryce
Sad to see you have to sell. If I was closer I would seriously consider buying this. Good luck with your sale and the move to Europe.
Nashco wrote:Knurled wrote: The failsafes, in this case, are the ones that open the HV battery's contactors if there is any fault detected. Exceeding the engine's RPM parameters doesn't result in electrocution or a probable fire...Have you ever heard of a money shift? Excessive RPMs absolutely can cause catastrophic failure of the engine or transmission. I assure you that one can start a fire by spraying hot oil onto a header or slicing a fuel line with shrapnel far easier than one can cause a high voltage fault on an OEM high voltage system (with only a software change) that is so extreme that it should have opened the contactors but did not.
And that is a deliberate fault while driving, not something that can happen at a standstill because a bolt fell into the battery pack and shorted a terminal to ground or something. If the PCM doesn't open the contactors when that happens, the likelihood of fire approaches 100%.
I know what you're saying, but right now, the safest approach is to keep things stock. IMO.
Good luck with your sale!
I saw this video a little while ago, really impressed with how much torque that little critter can pump out:
Knurled wrote: And that is a deliberate fault while driving, not something that can happen *at a standstill* because a bolt fell into the battery pack and shorted a terminal to ground or something. If the PCM doesn't open the contactors when that happens, the likelihood of fire approaches 100%. I know what you're saying, but right now, the safest approach is to keep things stock. IMO.
The safest thing is to stay at home and watch tv on the couch. But that's not what keeps SCCA going, racing cars does.
I don't think you do get what I'm saying. On a Honda Civic or a Miata, does the PCM open contactors of somebody drops a wrench onto the 12V battery terminals and creates a short to ground? What happens if the starter wire nut comes lose and the starter cable shorts to the metal fuel line? Does the PCM shut off the powertrain instantaneously if it detects that a fuel line is leaking due to a lose hose clamp? (Hint: All of those would cause a fire and the car would not only have no way of stopping it, the car wouldn't even detect a problem)
Gas cars are extremely dangerous, but we've learned to understand and accept their hazards because they're way more fun than sitting on the couch. EVs are actually significantly safer than gas cars, as you'd expect from any new technology development. However, even for those that know this to be true, somehow human evolution prevents us from trusting what we don't know.
I'm glad to explain why somebody dropping a screw into a battery pack is not only completely not feasible, but also not preventable under the current rules. I can also explain why dropping a screw into a high voltage battery pack won't cause an issue any worse than if you did the same thing with a 12V battery. I can help explain the electrical architecture of a high voltage car and how watchdogs exist to ensure that a simple single point failure won't allow for catastrophic problems. I can help people understand what safety and performance rules can and can't be checked for conformity.
But I won't do any of that if nobody cares to hear it. It's easy to say "no" but in this case that's definitely the wrong way to handle things. If you get wind that this rule really was created with an interest of safety, I'd appreciate if you could point out this thread/banter and my interest in adding a very informed viewpoint to the discussion. The offer stands.
In other news, the car seems to be sold. If I play my cards right, I'll get it back in a few years. Maybe I can fix the rules by then.
Bryce
There's also a technique to getting maximum acceleration out of the Spark EV. If you instantaneously mat the go pedal, torque limiting is much greater than if you roll into the accelerator. I'm sure those internet videos on EV acceleration were awesome, but I suspect subtleties like this are missed when you don't have an ass in a seat.
Well, maybe you can be the one to set the internet straight and take just one good vid.
Of course yours sells setup the way I would want and now they installed EV charging stations at work for me making the range of the Spark much more feasible. Timing was off by a couple days haha.
In reply to Socalbum :
Nope. I moved to Europe a couple of years ago, so it’s not really on my radar now.
Bryce
Rather than starting a new thread, I'll just add to this one since my 2016 Spark EV is really neither a build nor a project.
I went a different direction than Nashco, suspension-wise. Specifically, I went wider instead of trying to lower the car. I put on 15x8 Sparco FF1s (+25mm offset) and Kumho Ecsta V720s in 225/45R15. They add about 2" of width to the car to each side, 4" total, and stick out from under the fenders a bit. The stock springs are stiff enough that they don't rub, even under maximum-effort cornering.
Alignment is -1 degree camber and zero toe on all 4 corners. It only adjusts to -1, FWIW.
I took it up to Evergreen Speedway for an autocross and finished 10th of 19 in the FWD class. Evergreen doesn't do SCCA rules.
Some notes:
- the tires are L-O-U-D. V720s are noisy to start with, but the lack of engine noise accentuates the effect.
- the tires+wheels make the range drop by about 20%. Interestingly, they're 1.6 lbs lighter than the front stock wheels+tires and 2 lbs lighter than the rear.
- The wider track makes the car legal for SCCA events, near as I can tell.
- Not disabling traction control and not enabling sport mode seems to add about 2 seconds of time to a 1 minute run. It is waaay too easy to forget to do that.
- doing 12 runs makes the remaining range estimator incredibly conservative. Going home, driving 25 miles of actual distance only took about 17 miles of estimated distance.
Oh, hey, video.
Best run from in the car
Same run from the grandstand
(Yes, I know my driving leaves a lot to be desired.)
I took it back out to the same venue last weekend.
More observations:
- This time I got 5th out of 19, and I was leaving a lot of time out on the course. So even bone stock save wheels and tires, this car is a pretty solid autocrosser.
- Traction control stays turned off, but stabilitrak re-enables itself at some point, as Nashco observed in his 2014. I forgot to turn off traction control and turn on sport once, and once again that run was about 1.5 seconds slower than the others.
- On the street, I get about 4 mpK. Each run was about a mile (including the trip back to the grid) and sucked down 1.2 KWh. That's like going from miles per gallon to gallons per mile. Dumping that much power can heat batteries up a lot, which is probably why Chevy turned the torque down from 400 lb-ft to 340 after the 2014 model year.
- If I charge up between run groups, I don't have to spend a couple of hours after the race charging up to go home. There are a couple of free level II chargers out in the parking lot at Evergreen, and there are 110 and 220V outlets everywhere near the pits in the RV parking areas. Thanks, SnoPUD!
Neat stuff.
Are the Fiat 500e and BMW i3 still scca illegal due to height vs width? Or is that simply a matter of lowering.
I still haven't figured out what the story with this chubby boy is
In reply to cdeforrest :
All 500's except the abarth are written out for the height. Lowering can bring them into legal status. The i3 is right on the hairy edge of being legal. Adding wider wheels would bring it into compliance.
In reply to cdeforrest :
Couple inches lowered or widened look like it would work. BUT, I've not physically measured one. I'm working off the internet info I have to work with
The math is: Track width must be greater than or equal to height.
Sadly, a teenager using their phone while driving through a red light has totaled my poor Spark EV. I had bought it from the friend I sold it to last year, was daily driving it...but that didn't last long.
Since I don't have a Spark EV anymore, I’m selling my custom lowering suspension and race wheels+tires (including wheel spacers). Note that these were NOT on the car when it was hit, they’re in fine condition.
If you’re in Portland, San Francisco, or somewhere between, you’ll get a great deal so I don’t have to bother shipping them. Send me an email if you’re interested at (myusername)@gmail
It was a fun ride while it lasted! I'm looking forward to another EV racer in the future, maybe after SCCA stops playing the shell game with EV classing.
Bryce
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