Old Corolla Tacho's And Electronic Distributors

[philbey]

Guys

 

I'm not sure if I will have a problem or not, but from some discussion with the Auto Instruments repair guy, he reckons that old tacho dashes (KE10-11-16-18) will have trouble showing accurate readings on cars fitted with a later model Electronic dizzy.

 

I've done quite a bit of googling but haven't found much more info on it. I figure that a few of you doing tach dash swaps must surely have encountered this issue. Any idea what circuitry and goodies I might need to get it working correct?

 

I've found a couple of bits and pieces of reading but I'd like to hear what others have come across.

[the witzl]

My RA28 factory tacho has absolutely no issue reading the RPM with my electronic dissy and programmable ECU setup (EFI).

The original dissy was points system.

 

I just get the tacho to measure of the negative terminal of the coil, as per normal.

Still works for me, to this day.

[dfunkt]

not a ke1x, but i had the factory te27 cluster and an aftermarket 2 5/8" tacho wired up at the same time in my ke20 which has an elec dizzy.

 

factory tacho was running off the loom, the aftermarket was wired independently (like witzl, straight off the -ive @ coil).

 

factory tacho showed higher revs low down, but less revs up top. they crossed over around 2k rpm.

 

at idle, the factory showed 1000 and aftermarket showed 800. up high, the factory showed 6000 and aftermarket showed 6400.

 

i'd suggest buying/borrowing an aftermarket tacho just to see what it shows against your factory one if you're worried/unsure of it reading correctly.

[philbey]

Yeh, basically an old (40 years!) tacho will have issues with the signal from an electronic dizzy, but I haven't actually tried it. Incidentally I'm having trouble with my VDO, that might be a resistor thing though.

 

I was just wondering if some of the home-scientist types had come up with a fix on a corolla item or similar. Should be a reasonably straight forward fix. I'll whack my Sprinter dash in and rewire it and see what I get.....

[philbey]

More digging - looks like the datsun guys have the same problem when switching to Electronic ignitions...

 

http://www.ozdat.com/forum/viewtopic.php?f=2&t=1429&hilit=electronic+tacho

[parrot]

I have this thread saved in my subscribed threads on Toymods for a problem I expect to face.

 

Possibly of some relevance.

 

http://www.toymods.org.au/forums/showthread.php?t=22574

[philbey]

That's exactly what I was looking for when I started this thread originally, fantastic. I still need to look over the wiring diagram for the KE15 vs the KE10 dash to see if it'll work.

[Rolou]

That's exactly what I was looking for when I started this thread originally, fantastic. I still need to look over the wiring diagram for the KE15 vs the KE10 dash to see if it'll work.

hi philby i have an orig taco dash in my 69 sprinter and running an elect disy in a 7k as standard with no problems seems to be reading right don't forget the wiring is different on dash plugs ke15 ke10 cheers lou

[Rolou]

hi philby i have an orig taco dash in my 69 sprinter and running an elect disy in a 7k as standard with no problems seems to be reading right don't forget the wiring is different on dash plugs ke15 ke10 cheers lou

[philbey]

Cool thanks Lou that's good to know ill just whack it in. I did a list of terminal connection changes for the wiki so I'm up to speed on what wires need changing.