Ok so the afh is now in and running sweetly on bike carbs. Yes Tom, I'm a chav lol.

Is there anyway I can get the Skoda rev counter to work from the vw alternator ? I have removed the ecu and all associated wiring.

Also the Polo alternator has 2 small wires whereas the Skoda only has one. Which pin from vw alternator do I connect to the yellow Skoda wire?

What a difference to drive by the way. Such a simple bolt together conversion.

Thanks in advance folks

Pictures or it didn't happen...

Anyway, what alternator is it? And what ignition system are you running? You may be able to take a rev counter feed from the ignition coil.

Pictures tomorro. Awful internet here. Worse than dial up. Using the old mk2 dizzy so yes I should be able to take a feed from negative. Where to though?

Won't read anything from negative on coil or either alternator pin direct to black wire that ran to pin one.

Dismantled a spare set of clocks tonight but couldn't work out which wire was rev counter. only way I could get tachometer to move was to go direct to the 3 pins behind the pcd.

It's the Polo alternator

If I can't suss it I can use an aftermarket counter but would rather keep it on original clocks. Annoying cos everything else is working with no ecu :-(

it should work from the -tv side of the coil, lukes did from his coilpack before the AMP so maybe try it from the dizzy wiring to the AMP (think the coil itself is +tv switched so no pluse on the -tv side).

Pin 1 on the vw alternator is for the rectifier excited circuit/voltage regulator, because of the way it's wired it will also control the battery warning lamp on the dash.

it should work from the negative terminal on the ignition coil, you won't be able to take it from the hall effect switch because that will show double the actual rpm on the rev counter, also make sure the ignition amplifier module is attached to a heatsink otherwise it will likely die on you from heat.

it is possible to obtain a rpm signal from the alternator, but only on the diesel models which have a W terminal, a diesel alternator is a direct swap bolt on job, all the lugs are the same but check the pulley sizes, they are either 55mm or 60mm diameter and you need a Collection of spacers to swap the pulleys.

Pictures or it didn't happen...

Exactly. Any non-ECU, carburetor(s) engine conversion for Felicia is a must-see.

It took me a while to find this in my photobucket pages

this is the pinout for the two connectors up next to the battery where the fuel injection loom plugs in, ignore the colours they are for the engine side of the loom on the 1.6 model, but the pinout is the same.

The ecu is still connected up in this photo, ill get some better ones tonight now a lot of the wiring has been stripped out,  alternator is back on now and she is back on her wheels

 

that diagram is perfect tom, ill try connecting coil to that wire near the battery,  i couldn't for the life of me work out inside the clocks which wire was for the rev counter,     hopefully that does the trick,     i'm new to this electrics game,     hopefully have the mondeo brakes connected up tonight so i can take i for a safer run,   

 

booked in at bogg brothers next friday, 

 

first rally with new engine hopefully at pendrgon stages on 22nd Sept, 

 

 

 

 

 

Ah yes hold your horses a sec.... I was mooching along earlier mulling this problem over and I've hit a snag in my mind.

Both myself and jim have failed to spot the obvious flaw in the logic of using the negative coil terminal... There is a difference in rev counters that are on old school carb engines, carb rev counters only respond to e every other pulse from the coil, whereas efi rev counters work on every pulse....

there are 2 ignition events for every revolution of the engine, so if you wire into the coil the rev counter will show double the actual rpm which I alluded to earlier but I failed to register properly in my mind..

It might be possible to use a crank sensor from the 1300 engine instead to obtain the rpm signal but this is an inductive sensor so it makes only a tiny current, it would need to be amplified somehow, or what i would do is find an alternator from a diesel vw engine (doesn't matter what cc it is all the mounting lugs are the same) and make sure it's from an early model with a W terminal, but it may mean messing around with pulleys and spacers.. Or the other option is to open up your existing alternator for DIY surgery and solder a wire onto the stator output before the rectifier bridge and use that if you are feeling brave

The alternator pulley would need to be exactly half the size of the crankshaft pulley to obtain the correct output you need from it because you only need one pulse per revolution of the engine to drive the rev counter, this is derived from one of the 3 inpedendent stators (automotive alternators are 3 phase!)

I hope this all makes sense, if not I'd advise seeking help from an auto electrician.

i couldn't for the life of me work out inside the clocks which wire was for the rev counter, 

That is pin 7 of yellow connector. The color of the wire should be yellow/green.

Tom I'm sure the SPI felly rev counter uses the coil to trigger the rev counter.. can't for the life of me remember how I got the one working on DTA with the 16v but I'll have a look.

I'm pretty certain it comes from the ecu jimbo.

you are right it is the fav I was thinking of , I had Luke's rpm counter working from megasquirt until I started using an amplifier with switching +tv then it wouldn't work so I must have hooked it to the spark out wiring.

could he use the afh dizzy to run the ecu and have decent ign timing and rpm counter?

anyway a decent AFH with bike carbs should be going past the max on the std rev counter lol.. stick a clock in there instead and get a decent rev counter or a good shift light (I would rather a shift light to a rev counter if I had a choice of either)

Ordered a rev counter last night. With shift light. Tom lost me well and truly talking about opening alternators lol.

Hopefully have an hour or two tonight to Finnish Of a few little jobs.

Thanks for all your help.

little update here, 

 

not been touched an awful lot due to been busy racing lawnmowers, 

 

car went to bogg brothers to be setup,   ran lovely made good power,   then promptly snapped the cambelt taking it off the trailer at home, 

 

 

managed to pick up a 53k engine with history,   just managed to get that in and had problem after problem,    all seems to be sorted now which is just aswell as we are off to the Isle of Man rallying on tuesday,    just completed 20 odd miles off lane testing with no issues other than very hot brakes, 

 

 

will have to find some decent race brake fluid before we leave tuesday, 

 

engine is running sweet as a nut and pulls well through all gears,  only the sumpguard to bolt back on and she is ready at last, 

 

spots all wired up today to provide a little more light on the night stages