LC Model (2018-present)

Top speed!

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Old 06-18-18, 01:06 PM
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Boomin
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Default Top speed!

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Old 11-30-23, 09:23 PM
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hotwings
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Old 12-01-23, 04:14 PM
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fodalo
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Love it! approx 177 MPH not shabby. One problem, no room for error on the road u tracked this on. Nice Job!
Old 12-01-23, 06:05 PM
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iVector
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Hearing that V8 scream at the top end is intoxicating.
Old 12-02-23, 03:45 AM
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Originally Posted by hotwings
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Too late - you’ve revived an oldie but a goodie

I believe 286 kph = 177.717 mph

4 questions:

1) Does anyone know why it says the car has 477 hp instead of the usual rating of 471 hp we get in the USA?

2) Were there any mods done to the car?

3) Given that almost all cars read several mph too fast - how much speedometer error is built into the LC500? I’m gonna guess the car was doing about 170 mph in reality which is still impressive.

4) Has anyone seen a top speed run without the computerized governor limiting power above 6K rpm in 7th gear? I’m guessing a coupe could go a genuine 185 mph if ungoverned.

Heres another vid where it looks like the same tester hit 281 kph / 174.605 mph in a convertible.



Last edited by GatorGreg; 12-02-23 at 04:07 AM.
Old 12-04-23, 05:06 AM
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Originally Posted by GatorGreg
1) Does anyone know why it says the car has 477 hp instead of the usual rating of 471 hp we get in the USA?
There are many different hp scales. In Germany DIN standard is used. It is close but not same as US SAE Net number. In general difference is about 1hp for every 100hp and US number is smaller. For example 320 in Europe is 316 in USA. UK has yet another number scale.

In case of LC500 German official number is 464 which isn't in line with US 471. There has to be some difference between models or German number is not correct. Possibly 464 is old value from first LC500's and German imported just haven't updated it.

4) Has anyone seen a top speed run without the computerized governor limiting power above 6K rpm in 7th gear? I’m guessing a coupe could go a genuine 185 mph if ungoverned.
For some reason LC500 is slow for the hp it has even without governor. That is unless it can do 190+. Ferrari 550 has only about 15hp more and it can do 198mph. BMW E60 M5 has 507hp, likely larger frontal area and also does 200mph. Porsche 928 GTS has only 350hp (345 SAE) and can do 171mph. LC clearly wasn't tuned for autobahn bragging rights.
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Old 12-04-23, 05:52 PM
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LCIncline
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I was able to max it out to 154MPH in the USA before some limiter kicked in. There was definitely more in it. 21' Convertible.
Old 12-08-23, 01:23 AM
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The 477 is PS, the European measurement.
US cars don’t have the EU-mandated gas particulate filter which knocks engine bhp down from 471 to 464. This filter came in in the UK in 2018 so some of our early 2017/18 UK cars get the same 471 bhp as the US, then later cars are all 464 bhp.
The gas particulate filter (GPF) also negatively affects the exhaust note. Removing it throws engine fault lights and means the car won’t pass annual safety/emissions/condition tests.. unless you know a friendly tester.
The farcical emissions bobbins is mostly why the LC is being discontinued in the EU/UK as of the last couple of weeks. RIP.
This car is heeeavy and a little light on torque so I’d guess that’s why it’ll ‘only’ hit 175-ish.
Old 12-08-23, 01:03 PM
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JCtx
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Originally Posted by GatorGreg
Has anyone seen a top speed run without the computerized governor limiting power above 6K rpm in 7th gear?
I don't think it's governed; it's just can't go any faster. And I'm surprised it can actually do an actual 170 (or thereabouts); it's a whale of a car, and with a substantial frontal area. And yes, we don't know if the car had any mods (including different tires, and tire pressures), plus altitude, ambient temperature, road inclination, wind speed/direction, etc. All of that affects how fast the car can go too. But to be honest, I probably wouldn't feel like doing anything above 150 on a car like that, but that's just me.
Old 12-08-23, 02:14 PM
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Originally Posted by JCtx
I don't think it's governed; it's just can't go any faster. And I'm surprised it can actually do an actual 170 (or thereabouts); it's a whale of a car, and with a substantial frontal area. And yes, we don't know if the car had any mods (including different tires, and tire pressures), plus altitude, ambient temperature, road inclination, wind speed/direction, etc. All of that affects how fast the car can go too. But to be honest, I probably wouldn't feel like doing anything above 150 on a car like that, but that's just me.
I’m 95% sure it’s governed - see the sticky thread entitled “Replacing LC500 Torsen diff with LC500h one!” for details. Our cars will do 91 mph at under 2,000 rpm in 10th gear (see my pic below) which means they are geared to do over 300 mph in the pure vacuum of outer space at red line





Last edited by GatorGreg; 12-08-23 at 02:19 PM.
Old 12-08-23, 02:19 PM
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JCtx
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Even if it is, it'd only be a few mph, if at all. It's pretty much maxed out at that speed. Even a new M3 ungoverned tops out at 172 (real speed), and it's a smaller and lighter car, with about the same power. Can't defy physics.
Old 12-08-23, 02:38 PM
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Originally Posted by JCtx
Even if it is, it'd only be a few mph, if at all. It's pretty much maxed out at that speed. Even a new M3 ungoverned tops out at 172 (real speed), and it's a smaller and lighter car, with about the same power. Can't defy physics.
I disagree - if you watch the video around the 6:30 mark you’ll see it upshift at near redline from 6th to 7th gear and his speed continues to steadily increase by roughly 1 kph every second until he hits 6,000 rpm’s where it’s inexplicably prevented from revving any higher than 6,000 rpm in 7th gear, just as reported in the diff swap thread - so it’s almost certainly governed and I would guesstimate it still had another 20 kph to go.

Heres the post by breplica from the other thread:

Originally Posted by breplica
Guys, I need to make a small addendum to my earlier review of the differential swap regarding the top speed

In my original review, I mentioned the top speed would remain unchanged because the electronically limited top speed of 285km/h is reached at 6000rpm in 7th gear, which means that even with shorter gears, the car could simply rev higher (or in a higher gear) to get to that aforementioned 285km/h speed limit

Well, I was wrong

My assumption was that the 'speed limiter' in our LC500s are based on speedo readings. This is not the case!

The 'speed limit' is actually an 'rpm limit' - it simply stops producing power at 6000rpm in 7th gear onwards. On stock gearing, that is at 285km/h thereabouts. With this new differential, the speed at that gear/rpm is about 245km/h indicated. I have personally verified this at those speeds (don't ask me how I did it lol). Once you hit 6000rpm/7th gear/245km/h the car goes into a soft limiter mode where with the throttle pinned the car just maintains that rpm/speed and will not upshift. There is no sound/warning/alert from the engine, it just feels like someone turned the cruise control on at the limit rpm. In case anyone is wondering there is definitely nothing wrong with the car: I went in excess of 260km/h on it some time before I swapped out the differential

For most people I assume it wont matter. I doubt you would spend much, if any, time at those speeds, in which case then you don't have to worry about it. I'll be looking into getting myself a speed limiter removing device like the one made by Blitz or Tom's (which i suspect are the same units, just rebranded) and report back to let you guys know if it worked

285km/h - 177mph
245km/h - 152mph

for my american friends

In case anyone wants to see what the top speed limiter behaviour is like, go to 6:35 on this video: https://www.youtube.com/watch?v=Q3Ka...nnel=AutoTopNL The video cuts away abruptly just after he hits the limiter but you can see the rpm bouncing back and forth at 6000rpm (speed 285/286kmh) for a second or two before it does

Last edited by GatorGreg; 12-08-23 at 02:53 PM.
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