Jump to content
The mkiv Supra Owners Club

Where does the tacho sit when ignition is on?


dini_the_owl

Recommended Posts

It sits at 0, but only because of the pin that stops it reading less. If you just line it up with zero it will read wrong. You need to get the car warm and then put it back with the engine running at the warm idle speed (800rpm or so IIRC).

Link to comment
Share on other sites

I would rather no do it that way as your then fudging the tacho itself to read what you want, the tacho has a preload when it gets a voltage feed as you may be aware, although there is no actual signal from the ignitor or ecu it still gets a power source which causes it to shift the needle to a position being either marker 1 or 2, I have had to change this as my old n/a one does not work the same as the tt as the signal is from the ecu not the ignitor, and with it being a new engine it does seem to be idling higher than usual as i can tell from the engine note once the thermostat has opened at warm idle, im gonna get her tuned anyway so i dont want to fudge the reading as it were.

As i never saw the tickover before on this motor i just wanted to know where the rev counter sits when the ignition is turned on and the preload is activated, the engine must not be running though.

any helpers please

untitled.jpg

Link to comment
Share on other sites

Hi simon,

yes you cant set the thing up with the power off definately as you stated, if you set it when its off the preload will kick in and it will set itself to around 2k,what you need to do is install the pannel without the needle and turn the ignition on,once it has power it needs to be pushed on at marker 1 or 2 this is what i need to know, but preferebly from someone who has completely stock dials....there must be someone?

Link to comment
Share on other sites

Hi simon,

yes you cant set the thing up with the power off definately as you stated, if you set it when its off the preload will kick in and it will set itself to around 2k,what you need to do is install the pannel without the needle and turn the ignition on,once it has power it needs to be pushed on at marker 1 or 2 this is what i need to know, but preferebly from someone who has completely stock dials....there must be someone?

 

That's what I did, it still overread.

Link to comment
Share on other sites

It sits at 0, but only because of the pin that stops it reading less. If you just line it up with zero it will read wrong. You need to get the car warm and then put it back with the engine running at the warm idle speed (800rpm or so IIRC).

650rpm I believe, Si. That's what my e01 used to read the tickover as anyway. I'm sure it's more accurate than the stock tach

I would rather no do it that way as your then fudging the tacho itself to read what you want,
I disagree. Doing it that way makes it more accurate than the tacho previously was.

If you know it's reving at say 650rpm and you fit the needle in that position it's gotta be right, hasnt it?

Link to comment
Share on other sites

I don't make much use of the rev counter . It's easy to judge if it's idling correctly and I always listen to the engine note when driving so I know when it's time to change gear.

 

Surely just taking it off and putting it back on when idling to get it approximately right will be good enough. :)

Link to comment
Share on other sites

yes but if you dont know what the motor is reving at how am i supposed to set it up correctly,the only other way and im not sure it is possible to do it is attach an aftermarket tacho to the negative side of the coil or im sure theres a parallel feed to the diagnostics plug in the engine bay(poss black and white wire) i could use but i do not have an aftermarket one and im not totaly sure it would work anyhow as the coil and packs operate differently to the standard distributor, its a very simple request, im sorry i just need conformation.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.