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I saw this flame war on youtube and reddit.

I noticed that there was a statement from the driver about crosswinds blowing him onto the shoulder during his fastest run. However, I didn't see anything like that in the video. I assumed this meant they didn't want to show that run because the potential danger of being blown off the road wouldn't look good. Perhaps they mixed the speed data with a safer run from earlier in the day. This would explain the discrepancies.

If this is true, perhaps they are simply using the calibration talk as a red herring to distract from the misleading video. This scenario would allow them to not take responsibility and comeback with a genuine record.

They pretty much got caught blatantly lying. It’s possible that Shelby didn’t know it was faked at first, but by now he’s had the chance to find out and is complicit in the lie since he hasn’t confessed. I think a lot of other companies are going easy on them because they have also cheated and don’t want to start throwing stones in their zillion dollar sky castles, lest all the ultra rich owners that never drive their cars find out it’s a lie.

But expect to see a lot of hemming and hawing about how they’re having a tough time getting this next attempt scheduled and ask the permits in place. Because it isn’t going to happen. If it could, then they would have released the real footage and data to begin with.

So what exactly makes you think it's not possible for this car to achieve that speed? Do you think all of the publicly released stats are a lie?
The publicly released stats by them? Yes I think they are a lie for now, they’ve been shown to be dishonest. If a Tuatara owner wants to post specs that weren’t measured with the help of SSC, then I might believe them. But so far the independent analysis points to the car not going that fast.

This wasn’t an “editing” error where the framerate of the video accidentally was slowed down, it wasn’t a GPS calibration error, it was a company being caught in a lie. It happens from time to time, especially in motorsport.

Edit: to clarify, it’s not on me to prove that the car isn’t the fastest in the world. It’s on SSC, which is making the claim, to prove it. That their first attempt has been debunked means they will be given more scrutiny the next time around, and I’m not confident that they will do it. Because if this was just an editing error, why don’t they just go back to their footage and show us the real stuff? Did it conveniently get deleted?

That's valid, there's certainly something going on with the video thing. I guess my current thinking is that trying to fake the video in the first place would be tremendously stupid. Then on top of that to do such a bad job. So maybe it was an accident in video editing. But yeah, it's possible they're completely full of shit.
This is the wonder of the internet, the clues, anomalies and illogical, contradictory evidence people pick up on and expose like a crowd sourced episode of the old TV show 'Columbo'.

It's great that Shelby have accepted this, not crying 'tin foil hat', conspiracy theorists etc etc as so often happens with higher stakes anomalies

Sure they have accepted, but it's the only way to save face. Let's not forget that they did put out press releases (that are still up btw [0] [1]) falsely claiming that "Officials were on site to verify all world record criteria was met -- including review of Dewetron GPS measurements" which then prompted Dewetron themselves to distance themselves and post several comments and their own statements denying that claim [2].

Only when evidence and press/public attention started increasing did SSC then miraculously also started finding inconsistencies in the videos, etc etc. But at this point, their only options were to either admit to their wrongdoing or go along and side with the people that, by this time, already had pretty damning reports and proofs that the evidence for the "record" was very sketchy. If you haven't seen, you should check out Shmee150's video [3]

So, to me this was either purposely done for attention/press or the SSC people were really incompetent at trying to break this kind of record without proper measurement tools and official/independent reviewers. Something like this should, imho, be done as professionally and with as much redundancy as possible before any wild claim is made and press releases issued. It should never have come to a point where a few car enthusiasts on youtube can, from just a video and basic math/physics and knowing your own car parts, figure out that your record claims are false or at least very inaccurate. It has never happened when Bugatti or Koenigsegg broke the records. But now, if you search for "fastest production car" on Google, you get a whole lot of SSC results so, in a way, I guess they have succeeded.

[0] https://www.sscnorthamerica.com/news/ssc-tuatara-hypercar-ea...

[1] https://www.sscnorthamerica.com/news/dewetron-validates-ssc-...

[2] https://www.autodevot.com/wp-content/uploads/2020/10/Dewetro...

[3] https://youtu.be/nPXXGTuQKbk

SSC is not the same as Shelby American.
The inaccurate information (added by a semi-anonymous ipv6 user not logged in) is still up on Wikipedia:

https://en.wikipedia.org/w/index.php?title=Nevada_State_Rout...

And someone just fixed it shortly after your post. Thanks, I guess?
That was half of the idea, WP doesn't let you edit from a VPN even with an account. :)
That's the part I was thanking you for ;), since I could not possibly know if you fixed it yourself.

And I would not have expected you to write about something that needs to be changed (in that tone) and doing it yourself immediately afterwards. Why then write about it before fixing it, or in fact at all. Didn't make sense to me.

Also, my thank you could be seen as equally directed towards the stranger that got your hint.

I have irrationally strong feelings about production car speed records.

Firstly,

>Bugatti's claimed 300-mph-breaking Chiron run was never going to count

As much as they would like to believe otherwise, Guiness World Records can not create truth. If the Chiron goes faster than the SSC, it's the fastest production car. That's it. Two way runs & proper filming are an important factor if you're trying to decide who gets the piece of paper but there's nothing 'official' about it. If someone goes faster but never tells anyone, they still went faster.

That is apart from one point: the Chiron isn't a production car. But neither is the SSC. Nor the Veyron nor the Agera RS. If you don't believe me, try to buy one. No matter how much money you have, or at what time you try to do it, you can't. All of these cars have extremely limited units sold only to people with an existing relationship with the company. All of them set records with special editions. That's just a modified car. If there are only 25 Agera RSes & every one is modified for the owner, how do you establish the one that did the record isn't just the equivalent of a binned, liquid oxygen-cooled CPU that dies after the record setting run? You can't even drive the Veyron away from a record setting attempt: you need to replace its $40000 tyres.

Bugatti's record was once in doubt because they deactivated the speed limiter for the run. This was later retracted because it's not actually about trying to set consistent rules, it's about creating marketing material for Volkswagen's halo car. Which is why they won't let anybody else run their faster cars on their track.

Other, assorted viewpoints:

- If your car is just a modified Lotus, it doesn't count.

- For bidirectional attempts, how can you say that a car has a top speed of C mph when C = A+B/2 mph and A>B? That's an invented figure.

>- For bidirectional attempts, how can you say that a car has a top speed of C mph when C = A+B/2 mph and A>B? That's an invented figure.

I agree that (A+B)/2 is an invented figure, but I think the logic of "This is the maximum a car can do without external factors" is a reasonable thing to agree on as a top-speed, and wind is an external factor. Otherwise a lot of cars can set their top speed by being dropped from a sky scraper, and the testing would get unreasonably expensive. (A+B)/2 is probably a good first approximation to a wind-neutral value (and a gravity neutral value too).

On that note, a Porsche 911 Turbo races 1 mile against a VW Beetle dropped from a helicopter. I won't spoil the ending.

https://www.youtube.com/watch?v=SiAbcw5s9_8

But based on the Beetle's terminal velocity here, this strategy for setting a car's top speed will only work for cars that can't drive particularly fast.

Otherwise a lot of cars can set their top speed by being dropped from a sky scraper, and the testing would get unreasonably expensive.

Dropping a $25,000 Camry from an airplane might actually be cheaper than a single speed run of these hypercars, where they burn through a $40,000 set of tires....

I highly doubt the terminal velocity of any production car is even close to the top speed records in discussion here.
I was curious, so I ran the numbers on a Toyota Camry. With a mass of 1447 kg, a cross-sectional area of 2.7 square meters, and a drag coefficient of 0.28, it would have a terminal velocity of 391 mph. Other cars which are both heavier and more aerodynamic (e.g. a Tesla Model S) could reach even higher top speeds.
You'd need some sort of drogue chute or fins to keep it pointed nose-down, otherwise it'd tumble like the Beetle in the Top Gear episode just posted.

Or maybe being a rear-engined car put the Beetle at a unique disadvantage, and the Camry would orient itself just fine.

Junkyards are easy, who's got a helicopter-pilot friend and some land?

Ha! Sorry - I hadn’t seen your comment when I started mine. Yeah that engine up front will help I think!
For it to be aerodynamically stable you need the center of mass to be less than ~25% from one end. I don't think a Camry or Model S will do that, it will need stabilization fins.
For the Tesla, it might help to fill the frunk with water containers. That should bring the center of mass forward and up a little.
So drop an old 50's car with big fins and an empty tank ....
Surely this appears quick, but does this Camry maintain ideal orientation all the way to terminal velocity?

Hmmm, one could imagine using the front wheel drive as a flywheel for some attitude control...

Me thinks a drop test is in order.

Given that you can get away with a production run of 25 and still count just get the cheapest car on the market, stick some fins on it and sell 24 of them at slight discount from cost (include instructions for fin removal). Likely still cheaper than one run of a supercar.
The Veyron definitely was a production car if you had the money at the time.

As a wider point, the original Veyron had all the bells and whistles you'd expect from a mercedes S-class (for example), as opposed to being a stripped down racer.

The base Veyron didn't set the record. There were only 35 of the model that did.
Koenigsegg’s production list is capped, yes, but it doesn’t require a pre-existing relationship.

I work with a group of people who have built a car sharing club. I procured a Jesko production slot for the club and I have no existing relationship with Koenigsegg, nor any similar relationships with any major super or hypercar manufacturers.

> I procured a Jesko production slot for the club ...

How does that work? :)

> If someone goes faster but never tells anyone, they still went faster.

That's true, and I certainly am not the authority here nor am I knowledgeable enough to pretend to be one....But this reminds me of an argument I had once with someone about Short Takeoff & Landing airplane competitions.

They were bringing up how a group in Alaska was totally incorrect in claiming the competitors at their event were setting world records because (paraphrased) "well I know a guy whose uncle in Idaho took off in a foot less than that on his mountain airstrip, so that video isn't of the world record.".

Did he? Maybe. I can't prove either way. But the difference is, these guys are the, or at least an, authority on STOL world records. If you are serious about setting a record like that, you're going to participate in one of these events. Uncle Jimmy might be a pretty dang good pilot but it really doesn't matter if nobody was there to see it. And the pilots in these all agree that this group is the authority, so why would they recognize a "record" from someone outside it?

(comment deleted)
> Two way runs & proper filming are an important factor if you're trying to decide who gets the piece of paper but there's nothing 'official' about it.

The FIA, which sanctions all land speed record attempts, disagrees: Two runs, in opposite directions, with no more than 1 hour between the runs.

Same argument holds though.

If Elon decided to go run a special build Tesla with a new "Infinite Insanity" mode and did 350mph - without Guinness or FIA observers or sanctions, that'd be a thing, and sure it wouldn't qualify for any "official Guinness/FIA piece of paper", but I have no doubt Tesla Marketing would mount a magnificent press campaign with totally convincing proof of their claimed numbers.

(I totally agree that if you _want_ to make claims like that, you should abide by commonly held agreements and recognised authorities. But Elon does dumb shit all the time, and may well be the sort of guy who chooses _not_ to follow FIA rules to intentionally generate social media "engagement" and "vitality"...)

> there's nothing 'official' about it. If someone goes faster but never tells anyone, they still went faster

The word "official" refers to authority, not to reality. I'm using the official definition.

epistemics vs metaphysics.
This is it. There’s no difference between someone who goes faster and someone who claims to go faster if there’s no one to validate the result.

Bugatti’s “oh yeah we went superfast but we won’t bother to validate the record” is not very different from “my dad did 100mph once.”

I hope someone can tell CERN they need their particle physics verified by GWR.
Weak argument.

1. CERN is made of scientists; Their job is to measure stuff. SSC relied on a third party.

2. Their published studies are indeed open to replication/verification. "Hey we just achieved speed faster than light, believe us" doesn't just happen.

Why are the editors of a novelty book the authority and not, for instance, the FIA? GWR don't accept some kinds of records, does that mean they don't have one?
From the sounds of this there's two possible outcomes (assuming good faith): They run again and set somewhere >300mph. If they do that then it's reasonable to say that the original run was legitimate. More likely they run again and they look very silly because all their calibration was screwed and their speeds are a long way off.

There's always the third possibility - shenanigans. In which case they'll either pull more shenanigans or they'll just try and slink away.

In the meantime it sounds like the record can be safely ignored.

I don't know what the gearing looks like on this car, and I honestly don't care enough to look it up, but why do you and the article seem to think a car with 1750 (claimed) horsepower might be slower than one with 1160 (claimed) horsepower?
In the video you can guess that the engine power wasn't the limit at all. It was still accelerating super fast when reaching their top speed.
So that leaves us with two possible reasons the car couldn't have achieved the speed they're claiming. One, it wasn't actually geared to go that fast. Or two, the driver lifted because the car was unstable or he was afraid the tires were gonna explode or something.

It seems unlikely that people capable of building a car like this would have released a claimed speed that their car was incapable of reaching due to gearing. Then again, I've seen a lot of stupid things in my time racing.

Just 3 general reasons this could be true:

1. some engines will heat soak and lose more power than others under extended load, which doing 300mph will take, and the tuatara is a smaller engine running a lot of boost, more likely to lose power over time compared to some of the other hypercars with larger engines or partial electric power boosts.

2. gearing

3. aerodynamics. not just drag but will the car become airborne/impossible to control, etc

I kind of hope that team doesn't manage to go over 300mph. I'm sure they can manage to make enough power to do it, but I don't think they have the team that can go that fast at all safely.
Gps has no calibration process which would affect this in any way.
They probably use some RTK / dGPS setup for increased accuracy, which does need calibration.
Actual RTK/dGPS makes GPS more accurate, not less. If it doesn’t lock, the software should fall back to regular GPS.

Unless they were abusing the system by putting the dGPS reference station on a moving vehicle going the opposite direction or simply feeding spoofed correction data into the GPS.

I'm ignorant about speed tests. Given that distance is constant, wouldn't two synchronized timers be simpler than using GPS? And potentially more accurate?
I think timing it between two points will give you average speed between them. But this record is about top speed.
Any measurement inaccuracy or calibration issue here is going to be <1mph anyway...

It could never explain what was seen. Either someone foolishly read km/h numbers as mph, or the whole thing is faked. Considering the silly animation of the camera view on the video, I suspect the latter...

Practically every modern receiver works fine under 700 mph(edit: apparently the COCOM limits are approximately 1,200 mph). But the data can be tampered with, and if you’re not clever about how you do it there will be some discrepancies. Presumably a company validating their data would be a relatively trustworthy way to catch the tampering. There are a couple people on Strava (a fitness app) that doctor their GPS data to shave a few seconds of their times and take the top spot on the leaderboard. Sometimes they get caught because of the discrepancies.

This is really about Shelby getting caught with a doctored video and lying about a fake record but the author is too nice to call them out on it.

It is very hard for me to understand what they're referring to with discussion of calibration. They would presumably be using some type of augmented GPS/differential GPS which could require calibrated ground stations depending on accuracy targets, but the error you'd get from using unaugmented GPS or a low-setup augmented GPS like WAAS wouldn't be large enough to account for the errors discussed here. A cheap consumer GPS receiver like the one in your phone shouldn't produce the errors in question over a meaningful distance outside of some really fringe situations.

One of the specific claims is that the GPS equipment doesn't show a speed of zero when the vehicle is not moving - it's hard to understand how this would happen, a poorly set up DGPS scheme would not produce a 20mph rate of change in fixes for a non-moving object unless it was seriously defective.

All in all it feels a lot like the "calibration" here is just a hand-waving excuse for the outcome - the margin here is so large that calibration issues are not going to account for it unless there was outright incompetence.

The vendor involved, DEWE, makes various types of augmented GPS equipment but also inertial measurement products. Calibration would be a much bigger issue with inertial measurement and that could make more sense, but all the reporting on this says GPS was in use.

Wild seeing this.

I heard from a family member that this was _about_ to happen.

Specifically, these records occur on a stretch of "Blue Diamond Highway" between Pahrump, NV and Las Vegas, NV. This is the spot right before it splits into a divided highway. https://goo.gl/maps/nom16aarrpDVymFj6

They'd just finished up years of construction in the area and allowed it's use (since it shuts down all traffic going over the mountain for folks commuting into Las Vegas).

I used Audacity (and YouTube-dl) a few days ago to have an estimation of the top speed using the SSC information such as the gearbox ratios and the size of the tires, and the sound of the engine in the YouTube video.

Because it's actually simple to listen how fast an engine rotates, I found that they went slower than what is advertised and that the engine didn't rotate as fast as they claim. I computed 7530rpm and they claim 8600rpm.

I posted it on HN and I hope it's ok to post it again as a comment : https://fungiboletus.github.io/ssc-rpm/

Just curious, did you take into account any possible doppler shift of the frequencies?
No, should I have? The microphone was inside the car.
If sound source and sensor were at a fixed distance from each other then no.
when i first saw the video the rate of acceleration in the 300mph domain made no sense to me, given the power of the car. it didn’t creep up to 316! it should have.
Interesting analysis! I’ve seen the 2x multiplier myself, when I looked at the spectrogram of an AC induced whine in a speaker IIRC
> in V8 there is a cylinder firing at every 90° rotation which means 2 cylinder fire in one crankshaft rotation.

Your method and math checks out even without the tachometer observations - in a split-plane v8 (such as that in the scc tuatara) you have two cylinder fires per rotation of the engine. You have measured 251 cylinder fires per second (251hz) thus 125.5 rotations per second OR 7530/minute (RPM).

Hard to refute that.

Apparently (according to a YouTube video I watched :P) this is how they tell combustion engine powered torpedos apart via passive sonar. Analyzing the sound gives you the number of cylinders and number of propeller blades, which can identify the given torpedo type quite reliably.
Sonar tech here, this was true 20+ years ago but new torpedo and sub blade configurations are not only highly classified but any nuclear powered subs no longer even use blades to counter this exact problem. Only old russian and N. Korean subs can be identified this way anymore. Even when I was active duty 10 years ago china and us subs were basically silent and torpedoes surround themselves with air bubbles so the acustics dont really escape. You know something is coming at you fast but that it
One possible error in ground speed measurement: the tire likely grew in diameter as it spun faster. I don't know how large the effect is here, but it's worth checking or noting.
True, it could explain a small difference. But here the difference is huge, especially in terms of RPM.
Yeah, it wouldn't be enough to make such a huge difference. Nor would it explain the different RPM. Just wanted to note it for the sake of completeness.
I mean regardless of measurement, the gearbox ratios, engine RPM, and wheel/tire size plainly dictate maximum possible speed.

Why even use GPS for this, as opposed to a known distance and a clock, or an on-site laser (or whatever electromagnetic wave) based system? Seems like using satellites is unnecessarily complex and error prone(esp. civilian GPS).

because you don't know where in the run you're going to be at max speed or how long you can maintain it
The official land speed record uses a measured mile. You start as far back as you need to and then go through the traps and get timed. The Southern California Timing Association sets up time trials on the Bonneville Flats frequently. They routinely time speeds over 300MPH. These SSC guys need to go to a place like that and do it with timers and spectators, or shut up.
Tire size changes with speed and weight, weight changes with downforce, downforce changes with speed, winds, air temperature.

Maximum theoretical speed on a dyno, sure.

> weight changes with downforce

Your high school physic teacher is on line 1. Wants to talk to you about what "weight" means...

Mass does not change. But the effective pressure on the tires is as if the weight (which can be defined as the force required to support something) is indeed higher.
My high school physics teacher begs to disagree - weight does change with downforce.

Weight is the force the earth needs to provide to support the car. Mass remains constant except for burned fuel loss.

yes, I was referring to theoretical, mechanically limited speed.

It's not like the tires can expand in diameter 200% though. I'm sure that Michelin has parameterized tables for the tire's mechanical behavior that they are confident about by now. They aren't exactly new to tire engineering...

tires change in size with speed
you could use a maximum value from a parameterized table that I'm sure Michelin has for their top of the line super-car class tire.
Plainly wrong re: maximum possible speed.

Agree re: GPS, on-site laser traps timing an accurately measured distance is obviously preferable. I presume laziness prevails.

Sorry maybe I wasn't clear - it is a mechanical system with gear ratios directly coupled from the wheel to the engine. The maximum RPM of the engine, propagated through the lowest gear ratio, gives a hard limit regardless of the "real world" variables like wind resistance and friction.

The point was really if the mechanical system can only "turn" to a maximum theoretical speed of e.g. 300mph, then they clearly and obviously didn't exceed it, no matter what, unless the car transforms into an airplane at some point.

Sure, if you can quantify the maximum tire diameter at max rpm and top gear, you should be able to compute the maximum possible speed.

I don't personally know how much those tires deform at such speeds. My personal experience with sportbikes approaching 200mph has been it's not even enough to make up for the ~5% speedometer error that still indicated higher than actual around 190. But that's a much narrower and lighter tire, and 300mph is a different world.

Deploying ground-based infrastructure is difficult, especially in a place as inhospitable as salt flats.

GPS (really, multi-constellation GNSS these days) is not only easier to physically set up, it also gives you more data, and likely more accuracy. You don't save the PVT output of the receiver on the vehicle. (I mean, you could save that too, I guess.) You save the raw observables, and post-process along with data gathered at the same time by stationary reference stations. (Either run your own base, or use data from networks like unavco.)

This gives you a remarkably precise picture of the vehicle's position, motion, and acceleration, in 3 dimensions, throughout the entire run. If they want to be transparent about it, they'll publish a multiconstellation RINEX file of the whole shebang, so anyone can analyze it themselves. There might be fewer internet sleuths who know how to sling rtklib or gpstk than youtube-dl and audacity, but the ones who can, will produce a wealth of data.

For bonus points, put two receivers on the car, a few feet apart. This allows moving-baseline so you also get an orientation solution.

1: http://rtklib.com/

2: https://gitlab.com/sgl-ut/GPSTk

nobody's accusing the company of flat-out lying or deception in this case.

I don't know why not, because that's obviously exactly what they did. The engineers know the car can't go that fast. The helicopter pilot knows the car wasn't going that fast. They outright lied about the endorsement of the GPS company. You can't do that accidentally.

What is super wierd is the car probably can, at least set a genuine record. The engine power and aero are plausable. No sane driver would try on thouse tires, but the are plenty of mad ones. Why lie rather then just doing it expecially when they where always going to get caught?
SSC have never been faithful actors.
Reminds me of Nikola. Releasing fake video, company named to mislead investors and clients. SSC tried calling itself Shelby SuperCars LLC, took a lawsuit by Carroll Shelby International Inc. to make them stop.
Are there statements by engineers or the heli pilot, where is that coming from?
The article describes the top speed of the helicopter keeping pace with the car as being well below the stated record, ergo the pilot knows the car wasn't going that fast. It also states that analysis of the engine and gearbox ratios indicate the car is literally incapable of going that fast, therefore the engineers who built it know that as well.
Really, where are you getting that info? There are several analysis videos showing that the gearing in the car is designed to reach over 330mph.
Imagine your car only tops out at 250mph. Pffft how embarrassing.

Top speed is a pathetic and long-ago irrelevant metric as its immaterial to driving enjoyment (or anything really). While interesting and meaningful innovation will be done around weight, packaging, efficiency in the near future, none of this will derive from these circle-jerk Influencer “Hey guys” 330mph wankfests

You don't even have to be eagle-eyed to see that the roadside objects going past the car are passing by at well under, let's be generous, 150mph. While the GPS speed indicator shows 289, you can watch roadsigns on the right side of the car passing at relatively normal speeds.
No matter what speed they actually hit, I promise you it was faster than 150mph.
<tin foil hat>I wonder it it was 180mph? And somebody intentionally switched the speed displays to kmh? (that'd read 288kmh...)
In the comments section there is this fascinating bit of information (if true):

aki009 NOVEMBER 2, 2020 08:00 AM Not to provide an excuse for these guys, but that stretch of road is not too far from where the US military routinely degrades GPS signals for testing and training purposes. It might explain some of the inconsistencies in GPS data.

I haven't been paying attention to supercars for ages, but while briefly looking for photos of the Tuatara's powertrain I learned it's an NRE-sourced motor.

So let me get this straight; this is a $1.6M "supercar" with an NRE-supplied souped up Chevy (or is it a Ford?) V8 with the usual couple turbos hanging off it?

Nice profit margin.

It’s a custom engine, not a “souped up” one, costs about $30k. What’s the difference between having a partnership with an engine builder and doing it yourself?
So NRE is producing custom blocks pistons heads and cranks for SSC's supercar engines?

Because if it's just another Chevy v8 with some shiny manifolds and turbochargers hanging off it and an E85 compatible fuel system, it's nothing more than a souped up crate motor.

At 30k I'd personally be more interested in the h1v8 with turbos hanging off it, but it's still not something I'd be willing to pay $1M let alone $1.6M to get in a "supercar" package. That's insane IMO. And it's not that I'm against exploiting COTS parts for performance applications. It's just a matter of cost; Chevy-based powertrains are economical, this vehicle is not; hence: nice profit margin.

A quick google search shows that yes, they build the high perf engines in-house, starting from a bare block. It’s not a customized Chevy engine.
Since when do you even need a GPS to measure speed?
We live in a strange world.

On one side, we have a couple of people on keyboards, taking down dubious claims based on clear facts, logic and power of deduction.

On the other side, we have people on keyboards influencing millions using blatant lies, clear twisting of facts, easily verifiable incidents.

And yet no one holds the media accountable. That isn't strange, it's just stupid.
I could probably give benefit of the doubt right up to the point he lied about the GPS company. Sure, maybe even that was a misunderstanding or something. But it seems the most likely explanation is fraud.
Why is GPS even a thing with this? A few infrared gates to start/stop the clock and a known distance = computing the speed.

Instead lets time signals traveling in space and back. Sheesh.

GPS can provide highly accurate measurements using existing infrastructure and relatively low cost hardware. It also makes the results highly auditable since the GPS (and assisted GPS) system is public and well-documented, and open, standards-compliant methods exist in the surveying and DAQ industry for working with GPS data.

Laser gates certainly have advantages, but they require more setup and ultimately I am skeptical that they would provide more certainty than GPS results. As mentioned elsewhere a survey GPS receiver can produce raw data which can be processed after the fact as a form of audit, something not really possible with laser gates.

> I am skeptical that they would provide more certainty

Why on earth? They will literally produce two time stamps + known physical distance. What can be uncertain about that? Why is it any less auditable (or possible to tamper) then a GPS log?

Two timestamps would be trivial to fabricate while a raw GPS log would be technically complex to fabricate. Not impossible, but you'd need people with special expertise and probably custom software.
> including reviewing the Dewetron GPS measurements that tracked the speed runs using an average of 15 satellites.

I've got a bit off-topic question, but how accurate are speedometers in run-of-the-mill commercial cars?

I live near a pair of schools which set up those radar devices [1] showing how fast you're driving and it's rarely the same as my speedometer. Usually 2-5 km/hr below my cars number. So I always assume now that my car's number is more of a projection of the acceleration levels combined with the current speed to give a picture of how fast you're going to be traveling very shortly.

I've long been curious which one is more accurate. Apologies I've yet to do the rabbithole of figuring out how speedometers work vs how the radar speed sign works. I just assumed the radar device (on an empty road) is more accurate to real life than my car since it's a fixed external measure.

[1] https://en.wikipedia.org/wiki/Radar_speed_sign

What I've found, from a regulatory perspective, is that US regulations just require that speedometers be reasonably accurate, but EU regulations require that speedometers err in the direction of reading too high rather than too low. The EU rules must have their impact in the US because, at least anecdotally, it seems like just about every car's speedometer reads 2-3 mph high.

There's also apparently a rule in the US that requires that the speedometer never read low for commercial vehicles... probably another reason that the same rule gets applied to passenger vehicles, for parts commonality.

The speedometer is just based on the rotation of one of the axles, usually via a magnet and reed switch in modern cars. If you do the arithmetic you'll find that just tire wear can have a surprisingly large impact on the final speedometer indication, a few percent easily. Presumably if your tires are brand new the speedometer is much closer to accurate.

Thank you, this was a very informative reply and makes sense of what I've been seeing IRL. I live in Canada but our laws are almost always similar to the US.
Production car speed record is held by Elon Musk's Red coupe travelling at 20,000 miles and hour. Its going to be a while before they can confirm this travelling in opposite direction.