Poss it is voltage stabliser? But then I guess other instruments would be affected if so. About 4 different Rev counter fittings: Club has brand new early ones at discounted prices to members; else have some s/hand ones that might be better.....bet then you're not convinced it is r/c? Would seem most obvious.
Hey im pleased this topic has been approched, as my rev counter thinks the car idles at around 3000 rpm and flies to the max when im driving, so anything over around 2500 rpm sends it right around.
Yes, common problem on these. Mine plays up when interior is hot. In summer weather it will rev past 7000 . Club has new (early) rev counters in stock & there were two or three subsequent variations on wiring/fitting over the life of the model. We have a number of this type s/hand. Contact me via Spares link on web site if you want to try this route. We sell to non-members, but you won't get you 30% discount . Cheers. Glen.
I've not messed with the rev counter on my '68 yet, but the one on my '73 has an adjuster on the back. The rev-counter wiring is different so the '68 might not have one (I'll have a look in the work shop manual when I get a chance).
It might be the luminition causing the problem, perhaps they might be able to help offer advice.
Hello, I found this bloke very good, I forgot to sign the cheque and he still fixed it and sent it back trusting me to pay him. http://www.jdo10.pwp.blueyonder.co.uk
I have a 1968 fastback which I have owned for 12 months. The previous owner had fitted a Lumenition ignition. My rev counter idles at 4k and as soon as I pull away it goes up to 7K and stays there. I would really like to be able to get it to read correctly and have heard rumours of being able to re calibrate the counter or making loops in the cable. Any ideas?
Over reading rev counter
Posted - 16 Oct 2010 : 19:23:52
. Club has new (early) rev counters in stock & there were two or three subsequent variations on wiring/fitting over the life of the model. We have a number of this type s/hand. Contact me via Spares link on web site if you want to try this route. We sell to non-members, but you won't get you 30% discount 
. Cheers. Glen.