I know a lot of people are probably getting tired about the amount of EV talk right now, but this is breaking news. There's an electric sports racer thing running the 25 hours of Thunderhill right now. Endurance racing is probably the worst form of motorsport for EVs, so you have to give the team serious credit for trying it.
They're doing fast battery swaps that take almost exactly 2 minutes. That's basically a lap for the fast cars, although this thing is turning more like 2:12-2:15s. I don't recall what our fuel stop times were for the Miata teams I worked on, but I do remember we had to refuel every 45 (correction, 90) minutes. Looking at the live timing, I'm seeing 14-15 laps between battery changes which means somewhere around 35 minutes on a charge.
You can watch their first stop here: https://fb.watch/9HMeqHSc4B/ (I apologize for the FB link, I don't believe it's available anywhere else yet.
The vehicle is one of these: https://evsr.net/
Currently, they're 28th out of 36 cars - ahead of the almost-factory Honda team that's had to rip a new engine out of a car in the parking lot already.
I pitched hosting a 24 hour all EV race at PIR to the Board during my second interview for race manager.
In reply to Javelin (Forum Supporter) :
I wish that I'd known that you were planning on and made that pitch. I could have given you some guidance and put you in contact with people that would have provided enough revenue for hosting such an event that you would've gotten the position, as that event along would have more than covered your salary for the year.
If anyone wants to "watch" them on the timing (including lap times which clearly indicate pit stops), live timing is here: https://racehero.io/events/nasa-norcal-25-hrs-of-thunderhill-2021#show:detailed-info-overall-03
The car is #03.
In reply to Keith Tanner :
It appears that they're needing to stop for a battery change roughly every 14 laps, where as some other platforms, such as the K series Miata, are coming in every 39-40 laps.
I'm really curious about the battery cooling and any airflow around it to assist with heavy discharge rates any about paddock charging battery packs that have been pulled from the chassis already.
This is the car I did the body design work for. I am seriously bummed that I am unable to attend. Thanks Kieth for spotting and posting this.
In reply to Captdownshift (Forum Supporter) :
39-40 laps means they've got some sort of supplementary fuel tank on that Miata. I'm almost positive we were doing 45 minute sessions with the race-winning Miatas in 2012, but IIRC we were limted by regulations to no more than 10 gallons per stop. I think we had 18 gallons of useable capacity. Any idea which Miata is the K powered one? I can't spot it in the entry list.
(correction, we were not doing 45 minute sessions, see more accurate info in next post below)
The battery change video shows a very fast change with no obvious cooling connectors.
Oh man am I disappointed in the first pit stop. I bet they do a lot quicker by tomorrow morning.
I stand corrected on it being a K Miata, but car #13 is the Miata I was checking the data on.
In reply to Captdownshift (Forum Supporter) :
That'll be an interesting comparison to watch. I was wrong with my memory of 45 minute stints, I pulled out my logbook and it was indeed 90 minutes between fuel stops. You can stretch that a bit occasionally (18 gallon capacity, 10 gallon fill max so you have an 8 gallon "float") but over the race it would average out to that.
TurnerX19 said:
Oh man am I disappointed in the first pit stop. I bet they do a lot quicker by tomorrow morning.
Can you give us any insight into the car? Very cool that you were involved.
Remember that the lap times with pit stops also include a lap of the track as well as the pit lane time. Looks like the fastest pit lap is a 4:42 bracketed by a 2:19 and 2:22, so that says the battery change takes about 2:20 including pit lane time. First stop was a 5:05. I don't know what the time to transit the pit lane is.
It appears they just pulled off a 10.511 second lap. That's really moving :) The lap before was a 2:01.570, I think maybe we need to add those together. Did someone have to correct a lap count?
Hi! I am the Media Relations person for EVSR and the 25 was red flagged for fog. People are predicting no lift until 9/10 am tomorrow.
If you have any questions, post them here, but I check email way more often.
jenn@evsr.net
In reply to Keith Tanner :
We have been doing 2:15s from pit in , driver change, to pit out. We've had overheating issues with one of the two motors and some of stops are necessitating some attention there.
In reply to Captdownshift (Forum Supporter) :
If you look at our media on FB and YT you can see the battery boxes are constructed with perforated metal. The packs haven't had any overheating issues, whereas one of our motors has. The immediately get sent off to our charging station further away in the paddock and they are returned to us within two and a half to three hours fully charged and ready to go back into rotation.
We have a whole safety series under "Playlists"
https://youtube.com/c/ElectrifyingRacing
this is awesome. Thanks for posting!!
Great info, Jenn. Thanks. I applaud the team for taking on a significant challenge! This race is hard enough when you're dealing with proven tech like a Spec Miata.
The first pit stop cam across my FB feed. I'm super excited about this.
I don't care if they finish dead last. I'm excited to see them run and finish. Prove it can be done. Throw down the gauntlet for some big-money factory teams to get their acts together and refine the tech and process to be competitive.
In reply to JENNEVSR :
What is the driver line up, and who did the 2:05?
In reply to JENNEVSR :
Thank you so much for hopping in here and answering our questions.
In reply to TurnerX19 :
Charlie Greenhaus laid the 205. Right now Filipkowski is in the car, then Reid. Race Hero kinda sorta updates the drivers as I text with Timing
In reply to Captdownshift (Forum Supporter) :
Keep them coming
FYI, our pits will be more often and slightly longer as we swap every other stop between battery/driver changes and motor temp management