The online racing simulator
Spinoff : Speedo discussions
(85 posts, started )
Quote from SRR Marty :irl the speedo is connected to the front tyres. i have noticed that in several fwd cars i drove. locking brakes dropped the speedo down to zero, spinning wheels (in 1st gear on snow or ice) lets it jump up.

thats why i always was wondering why the RWD cars in LFS the speedo seems to work different, when revving up and letting the rear tyres slip, the speedo goes up, when using the e-brake, the speedo goes down.

maybe someone of the devs can explain how the speedo works in LFS.

Well, I'm not one of the Devs , but the speedo is linked to the gearbox, which means it doesn't matter if the car's a FWD, RWD or AWD. The speedo just shows the "speed" of the driven tires (with a locked diff al least, with an open diff it might be different of course) .
irl, cars fitted with ABS, the speedo uses the average speed of all the wheels.
If you have the value of the speed of each wheel why don't use it to to made the speedo as accurate as possible?

when i say irl i means every renault car since 199x fitted with ABS
Most cars I've owned have measured speed from the gearbox. I know this because in most of them I've changed the cable myself that goes from the Speedo to the gearbox.

With my current car I have no idea where it measures speed from. I haven't looked into it. I don't really care though, as long as it's accurate enough so I don't get fined!
Quote from Rotary :Most cars I've owned have measured speed from the gearbox. I know this because in most of them I've changed the cable myself that goes from the Speedo to the gearbox.

With my current car I have no idea where it measures speed from. I haven't looked into it. I don't really care though, as long as it's accurate enough so I don't get fined!

Well, that's right for cars where measurement and display is mechanical, but when it's done electrically it's taken from several points thinking of accurate and reliable system.
#80 - ssm
Quote from kcvpr :In real life, if your wheels were spinning, should one really be looking at their speedometer?

You inadvertently do... I mean like.. I would be going no were on a hill, so I have nothing to do as I have the pedal to the firewall and in top gear...
Just about every car in production today measures the dash displayed speed from the transmission, the wheel speed sensors are reserved for ABS and traction control. I have changed the speed sensor on alot of newer cars.

On cable driven cars it was either taken from the transmission or from one of the non driven wheels. The only examples I can think of right now that take it from a wheel are the DMC12 and older porsches. Other than that, they mostly take it from the transmission.
Quote from DragonCommando :Just about every car in production today measures the dash displayed speed from the transmission, the wheel speed sensors are reserved for ABS and traction control. I have changed the speed sensor on alot of newer cars.

On cable driven cars it was either taken from the transmission or from one of the non driven wheels. The only examples I can think of right now that take it from a wheel are the DMC12 and older porsches. Other than that, they mostly take it from the transmission.

I had to change right transmission in my '99 Clio after break a joint. The old one has XX marks and the new one was different (they say me that were compatible @#@#) and has YY marks for the speed sensor. As a result: ABS and speedo went crazy.

I don't know if other cars works like this, but as much as i know, renault cars do.
#83 - Riel
Quote from DragonCommando :Just about every car in production today measures the dash displayed speed from the transmission, the wheel speed sensors are reserved for ABS and traction control. I have changed the speed sensor on alot of newer cars.

On cable driven cars it was either taken from the transmission or from one of the non driven wheels. The only examples I can think of right now that take it from a wheel are the DMC12 and older porsches. Other than that, they mostly take it from the transmission.

??

Well, nowadays every wheel is just measured apart. The signal gets put on the car's databus. Every component that needs it gets it from there: abs, engine control, traction control, ESP, stability, whatever.

The speedsignal from differential is just not relevant anymore. That's for old cars ...
#84 - d6nn
i've heard that most cars measure speed from the rear bumper
well the speedo for me are ok. i use high resolution and 8x AA and i can see it rather well. i only ever look at it while driving in pitlane. One thing that bothers me and is not speedo is the revs display in FOX. its red all the way from center out. It would be nice if it was more colorfull, maybe from green to red.

Spinoff : Speedo discussions
(85 posts, started )
FGED GREDG RDFGDR GSFDG