Vehicle: Car: Communication
Giant external Tach   (+1, -2)  [vote for, against]
Shift dag namit!

A simpler version of the original post (in 2001). This is simply a giant tachometer mounted on the back of everybody’s car (that has a manual transmission). The readout, backlit of course, has a indicator sweep of 360 degrees to go from 0 - 6000 RPM respectively. The dial itself would at least 16 inches in diameter and the pointer would be huge enough to see from 100’s of feet. The point of the tach to everybody but the driver is safety. When you ’engine brake’ with a manual tranny you don’t have any way of letting the car following you that you slowing down, in till now. If the car following you starts to see they are getting close and they see your RPM’s dropping they can surmise why and slow accordingly. Inconvenience averted. Imagine the entertainment value added to the vehicle. Now people can watch your tach if they feel so inclined. Safety, entertainment, what am I missing?
-- evilpenguin, Aug 14 2007

Original Idea External_20Gear_20_26_20Rev_20Display
What I found before posting [evilpenguin, Aug 14 2007]

Decelerationlight Decelerationlight
Here it is [acurafan07, Aug 15 2007]

//Safety, entertainment, what am I missing?// The fact that any tach large enough to be seen from a good distance would only fit on the back of an SUV, a type of vehicle rarely found with a manual tranny or driver who wishes to engine brake. And the majority of cars these days redline at over 6,500 RPM, making the needed dial size even bigger.
-- acurafan07, Aug 14 2007


You could fool the car behind by revving the engine in neutral while simultaneously braking.
-- hippo, Aug 14 2007


How about a giant external 'tache? It would act a bit like a bumper when people did crash into you due to your unannounced engine braking.
-- Srimech, Aug 14 2007


Dali or Fu Manchu?
-- hippo, Aug 14 2007


No way could Fu Manchu drive a car!
-- theleopard, Aug 14 2007


Number One Son would drive.

Doh, that was Charlie Chan!
-- zen_tom, Aug 14 2007


Not wishing to dis the [evilpenguin], but seriously for a minute...

Suppose that the car's electronics detected the conditions for engine braking and simply illuminated the brake lights. That would actually be an implementable possible safety feature.
-- AllyAl, Aug 14 2007


Wouldn't even need electronics or any fancy thing. Just hook the "brake" lights up to an accelerometer. Make them deceleration lights. I don't really care if you have your foot on the brake, I just care if you are slowing down.
-- Galbinus_Caeli, Aug 14 2007


Actually. simplier that all that, when you engine brake you create a difference in engine vacume that could easily be dected by a pressure switch. I think my idea is just more fun to impliment.

//Not wishing to dis // I'm a big penguin, no need to sugar coat anything
-- evilpenguin521, Aug 14 2007


A pressure switch would be fooled by gearchanges; an accelerometer wouldn't.
-- david_scothern, Aug 14 2007


Maybe use both sensors to create an accurate output.
-- evilpenguin, Aug 14 2007


I bunned it. Not that I would want the thing on my car, but I sort of like the theory behind it.
-- xandram, Aug 14 2007


But it has already been halfbaked, I'll try to find the link.
-- acurafan07, Aug 14 2007


Please do acura... very intrested
-- evilpenguin, Aug 15 2007


Not a giant taco then? Damn.
-- imaginality, Aug 15 2007


No, this isn't really a taco, because it's a really big outer tachometer. That 'h' and the fact that it is no way edible makes this not a taco.
-- evilpenguin, Aug 15 2007


There it is. It was actually easier to find than I thought it would be.
-- acurafan07, Aug 15 2007


Interesting, but why a Tacho ? Wouldn't a giant speedo be the better option if it's the vehicle slowing down that you're concerned with (as opposed to a giant pair of speedo's which would just be wrong !)? Aside from which, car makers have already developed forward looking radar thingies that automatically brake your car if you get too close to the one in front.
-- Hairy Sock, Aug 15 2007



random, halfbakery