Aftermarket tachometer accuracy

[CMF_Tomlenn]

First one note, please forgive me for any spell errors I'll probably make since English is not my native language.

New here, all the way from the Netherlands, so one of the few left-hand drive Micra's on this site!

Now let's go on with the issue, I've installed an aftermarket tachometer to my 1993 1.3 LX recently and it works! It's from a brand called "Race Sport" (never heard of it). According to a switch on the back is suitable for 3, 4 and 8 cylinder engines.

The numbers "4,6,8" are printed in the plastic near the switch, but there's a sticker over it saying "4,3,8". That's one thing that's strange, but it should work.

Well I've set it up with wiring to the dizzy (blue wire on top, thanks for the tips on this forum I found using the search), dash ligts and contact 12V.

It's giving me this values (approximately):

Gear/KM/H|MP/H/RPM
0/0|0/750~850 depending on electricity load)
2/30|18,6/2000
3/50|31,1/2300
4/80|49,7/2700
5/80|49,7/2200
5/120|74,6/3300

Can anyone of you compare this to their original value given by the standard tachometer? It seems to me the values are a bit low, is this right?

Maybe my judgement is not so accurate since I've been driving a lot of turbodiesel powered cars, which have MUCH lower RPM's. My dad for example has a Almera/Pulsar powered by an 2,2 dCi Commonrail Turbodiesel engine and it runs at about 3000 RPM at about 145 KM/H (that's 90,1 MPH). I went driving it once on the German autobahn which is about 20 KM (12 miles) from here. The car runs about 3800 RPM at 195 KM/H (121 MPH), so that's not much. However it starts to redline at 5000 RPM.

I'd expect the Micra to have a higher RPM value am I right? The manual tells me that it should run at about 750 rpm idle, so my tachometer is giving me the correct value there anyway.

So can anyone please give me some speeds and RPMs to benchmark my tacho? Thanks in advance...

P.S. there is a good reason why I didn't just find an original gauge cluster, long story...

A few pictures made with my cellphone:

 

[CMF_evade]

those numbers sound about right, it'd say it'd be fine

 

[CMF_nz_aj]

Certainly not low, I thought they might be on the high side.
Speedo calibration & tyre diameter are another issue.

On a jap assembled K11 the rev counter version of the instrument binnacle can be just plugged in.
Most of the ones available are from automatic with the automatic gear indicators on the speedo. The speedo from the manual not revcounter instrument binnalce can be swapped in.

 

[CMF_Tomlenn]

Thanks for the reply, I'm using standard tyres so that's 155/70 R13. Everything else on my Micra is standard, I just wanted to have a tachometer. And I tried getting an original gauge cluster, but it was impossible to find one. Most people here driving a micra are old, very old. They don't care about having a tachometer, and a lot of the 1993 to 1996 Micra's are still on the road.