6 replies to this topic

[Scubasteve]

Bonjourno!

I have had a cheeky search of the forum but can't find the answer to the rather specific question I am putting forward.

I really want a rev counter but am a student and therefore pretty skint.

I have been watching three clock dials and speaking to the helpful gents from this here forum but cannot afford the £40 quid plus of them.

So I am wondering if there are any rev counters out there for not much more than twenty quid that can be used with the two ' rev counter' wires on the back of my two clock dash.

Any help or feedback would be much appreciated.

Many thanks

Steve

[dklawson]

If you don't mind generic tachometers mounted in something other than an original dash... there are lots of choices. Start by looking at eBay.

You also don't need to limit yourself to wiring that is already in place. A "modern" tachometer will have 4 or 5 wires to connect: earth, switched 12V power, a connection to coil (-), and one or two wires for illumination. That's it.

[Scubasteve]

Cheers DK!

Awesome, so as long as I go for one in the right rev range, negative earth that can be used on a 4 cylinder engine, I should be golden?

Is it quite easy wiring one in not using the ones coming off the original dash then?

I am, at best, a novice at wiring and at worse a complete numpty!

Many thanks

[mini 4o]

hi
look on ebay loads under £20 like this one Item number: 190559875270

john

[dklawson]

Wiring a modern tachometer is not difficult at all regardless of how comfortable you are with electrics.

Per my last post, you will have 4 or 5 wires to connect. The color codes are typically "generic" and go something like:
black = earth. Connect to a bare metal spot behind the dash. Got a stereo? Tap into the black wire for it.
red = +12V power. Connect to a fused +12V source. As above, if you've got a stereo, tap into its switched power.
green = sense wire to coil (-). That's your most difficult wire as you need to pull the wire through the firewall and run it all the way up to the ignition coil. Stay away from places the wire may become burned or pinched.
white = illumination. In older Lucas wiring schemes, red/white wires were for dash lamps and you would tap into one of those for the gauge light. For later cars, others will have to tell you the best place to get lamp power.
Lastly...
SOME illumination lamps have 2 wires, white as above and sometimes black. IF you have a lamp with 2 wires, the black wire can be connected to the same black/earth wire as above.

[Scubasteve]

Thank you so dklawson!!!!

I have purchased myself a 52mm tacho from the Ebay for under £20 so will hopefully receive that soon!

I will make sure to follow your advice on the old wiring, I am not on for melting anything unintentionally!!

Steve

[DanNomNom]

I just used the existing 2 wires behind the dash with mine, iirc the black/white one is the signal (connect it to green) and the other (can't remember what colour atm) can be connected to red, then the same as DK. This saved me loads of time, as I even used the connections already one the wire.
You can check that it is the correct wire by using a multimeter and earthing it, one wire should produce a steady voltage when the ignition is on, and the other should increase when you rev the car.
Edit to add
You can just see the rev counter I got in the corner of this pic:

DSC_6741 by DanBewsey, on Flickr

Edited by DanNomNom, 02 August 2011 - 10:06 AM.