I have a 50mm VDO tacko 0-8000 RPM - Has input select for cylinder numbers - 4, 6, and 8.

It is showing a higher RPM than the motor, It does not have an adjusting pot to "dial it in" to the correct RPM.

Anybody have an idea how to set it to show the correct RPM range?

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It's not a mini, but still a bloody lot of fun! (and keeps me poor)

It will have a calibration adjustment, it's just a case of getting to it.

You may need to open it up to find out where it is.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Bugger

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It's not a mini, but still a bloody lot of fun! (and keeps me poor)

I just pulled out the dash and dropped the tacho - found the pesky little adjusting screw - in the side of the body - not at the back where I first looked.

I have adjusted it back and no I have something close the the engine rpm.

That has taken a year and a half to getting around to fix!

I am going to drop out the windscreen and re do the rubbers next, re do the side screens and fit an original rear bumper - the joys never stop.

my modified dash:


My Beast:


Side view:


Back View

I have had the rear set covered in match vinal. I am also re making the rear bumper - fitting an original - as I manufactured this one and now the original spare tyre does not fit.

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It's not a mini, but still a bloody lot of fun! (and keeps me poor)

Love the dash, Andy!
Gives me ideas for mine...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

With the calibration, you will need to calibrate the tacho (using an accurate reference) in the range you are most interested in.

Depending on the value of the tacho, they are notoriously innaccurate at each end, and accurate in the middle. Or they are accurate down one end or the other, and innacurate for the rest.

So, measure the tacho against the reference writing down the values you get, and then decide where it is most important for you and your application to have the tacho accurate. Do you need it accurate at around idle, accurate in the middle range or at redline?

More usually you will find it convenient to calibrate the middle (cruising) rpm range, and having calibrated it yourself you will know the difference to add or subtract at higher and lower RPMs.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

I have an digital output, optical tacho at work - so I will check engine rpm and I will look at setting it in the mid range. Thanks for the advice!

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It's not a mini, but still a bloody lot of fun! (and keeps me poor)

Huh. Mine's the opposite (low), which is obviously more of a problem. Never thought to look for a trim pot. WIll go poking.....