Tachometer Retrofit 318i '85

[guuskolo]

Hello,

I was doing a bit of research into retrofitting a tacho/rev counter into an e30 318i from 1985 (m10b18).

now there are tons of tacho's for sale WITH feul economy guage, but i've been informed that these might not work with the old m10. is that true?

i've done some research into retrofitting guides from bmw themselves but those were in german so they might aswell be in chinese, i'm none the wiser.

long story short: what tacho's did the m10's have?

[guuskolo]

follow up question:
what will the economy gauge do if i would install one of the newer units.
because the internet says it uses rpm and speed signals as an input. i would say it wouldn't matter if it is an m10 or and m40 as long as the speed and rpm are the same. right ?

[Brianmoooore]

Economy gauge uses the road speed signal and a fuel rate signal.
Never had an injected M10, but both the carb. M10B18 E30s I have owned have had standard E30 clusters with rev. counter and economy gauge.

[guuskolo]

Thanks for the info. just ordered a new dashboard with a tacho and will be installing that some time this week.