Plasma speedos

[Howard]

Another question from me i'm afraid.......

My speedo reads to 140mph (its only a 230) if i fitted these (which reads to 160mph) would i need to have the speedo re-calibrated as obviously the numbers a re closer together on the 160 mph dial ......

If it would need re-calibrating - who would do it ? would it need to go to a stealer or is it a DIY job ?

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=72216&item=7948963699&rd=1

 

[miro]

Another question from me i'm afraid.......

My speedo reads to 140mph (its only a 230) if i fitted these (which reads to 160mph) would i need to have the speedo re-calibrated as obviously the numbers a re closer together on the 160 mph dial ......

If it would need re-calibrating - who would do it ? would it need to go to a stealer or is it a DIY job ?

A dial is calibrated to itself.

 

[Howard]

huh ?

 

[GRAV888]

I had 160 mph guages in my C180 that was meant to be 140mph.
There is VERY little difference at low speeds.
When you are reading 110mph on the 160's, you are only doing 100 really.
HTH

 

[Howard]

Is there enough of a difference to set off a 30mph camera using the old 30+10%+3mph rule ?

 

[Shude]

If the instrument cluster uses the speedpulse then you could buy another one with the correct gauge ranges on it, then mod that!

 

[GRAV888]

Is there enough of a difference to set off a 30mph camera using the old 30+10%+3mph rule ?

The best thing about being this way round, is that if it said 30, you would probably be doing about 29.
You are always gonna be doing less speed than it is showing, so therefore, no flashes

 

[Howard]

Ok..... sounds reasonable, how do i tell if it uses Speedpulse ?

Its quite old (1992) no cruise control, what do i look for ....

Thanks again

H

 

[Howard]

The best thing about being this way round, is that if it said 30, you would probably be doing about 29.
You are always gonna be doing less speed than it is showing, so therefore, no flashes

Cool !

 

[Shude]

Ok..... sounds reasonable, how do i tell if it uses Speedpulse ?

Its quite old (1992) no cruise control, what do i look for ....

I don't know how non-speedpulse ICs work, but I think they'd have some cable going to a spinning part in the engine or gearbox to work out the speed.

If it uses speedpulse it'll just know that 50 blips = 50 revolutions of the wheel, so that'd be about 100 metres, which in 10 seconds comes to about 22mph. Something like that anyway. You could use any gauge for that because it's a constant value.

 

[Howard]

There is a cable that screws onto the back of the speedo (not unlike a cable tv connection) when i took my speedo out , this was loose and was causing the needle to bounce up and down a lot at low revs, i tightened up the fitting and the bounce has got a lot better .... it didn't appear to be an electrical cable, more a mechanical one.


Hey w124's aren't the pinnacle of technology, they might be bombproof but they still have a wind up clock !!

Perhaps there is more resistance in the 160 mph speedo ?

 

[Shude]

Perhaps there is more resistance in the 160 mph speedo ?

That sounds pretty likely, probably compensates for the different speed range with some kind of gearing inside the cluster. Maybe I'm making it out to be more complicated than it is?