Topic: 450se tachometer into 280s

[Claudio]

I am aware that this question must have been answered a few thousand times, but i still don't get it:

Can i buy in ebay a whole instrument cluster from a w116 450se to use in my w116 280s?
Will the 8 cyl tacho work in my 6 cyl 110?

Thanks,
Claudio

[TJ 450]

I think the issue is that the tach runs off the coil input. Of course, a 6 cyl engine fires six time per revolution and so on. As MT stated in another post, the tach would need to be set up to account for this difference.

I have no idea how you would go about doing that, though, as I haven't looked at the circuits of these tachs in detail.

Tim

[oscar]

TJ's right.  No idea how one can be converted but basically an 8cylinder tach counts every 8th pulse and a 6 cylinder tach, every 6th pulse.

Further to that, the gearing behind the speedo/odo will be different too I presume.  I've compared a 280 and 350 speedo/odo and that was the case.  So look for a 280 tacho and or a complete 280 instrument cluster.