Z3 2.8

[hughandjen]

Hi everyone
I have just bought an old Z3. The Rev counter is no accurate. It is reading approx 1/3 higher revs than the car is doing?
Clutch is not slipping and the needle is smooth and doesn’t jump about.
Can anyone help
Thanks

[2 sMoKiN bArReLs]

How do you calculate that the tacho is reading high?

[hughandjen]

It’s approaching the red line when I’m in top gear and doing 70!!

[cobra kid]

hughandjen said:

It’s approaching the red line when I’m in top gear and doing 70!!

Ah, they all do that.

[Triumph Man]

Somebody put the clocks from a 4 cylinder car in it?

[hughandjen]

I was wondering that too.
Are they a different part number for the Rev counter for a 6 and a 4?

[2 sMoKiN bArReLs]

hughandjen said:

It’s approaching the red line when I’m in top gear and doing 70!!

Aha!

[motco]

hughandjen said:

I was wondering that too.
Are they a different part number for the Rev counter for a 6 and a 4?

Look in Realoem.com

[underphil]

hughandjen said:

It’s approaching the red line when I’m in top gear and doing 70!!

isn't that a lot higher than 1/3 higher?

that's more like double??

[WJNB]

The BMW Owners Club & their Forum would no doubt be a source of help.
First thing I did whenever buying an 'older' car was to join the relevant.

[hughandjen]

I have joined the Z3 owners club but they were no help.
Yes it is probably 50% out.

[motco]

hughandjen said:

I have joined the Z3 owners club but they were no help.
Yes it is probably 50% out.

6 is 50% more than 4. It could be the coding plug only that's wrong. I'm not sure (see Realoem) but the 6 cylinder cluster may well be a four cylinder cluster with different coding.

zroadster.org and zroadster.net are each worth a look but their search facilities are poor.

[buggalugs]

IIRC on the older cars it was some kind of jumper blocks or switches on the back of the unit for the 4/6 cly thing?

[hughandjen]

Thanks
I’ll have a look