Factory RPM/rev counter?

DonTPushIt · Force Sensitive Joined: 06 Apr 2015 Posts: 14

I currently run an aftermarket rev counter with my 1985 T25 2.0i ej20 setup - how do I get my VW rev counter to work instead?

Kai · Posted: Thu May 14, 2015 8:30 am Post subject:

What was the engine originally in your van? Petrol or diesel?
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DonTPushIt · Force Sensitive Joined: 06 Apr 2015 Posts: 14

Petrol

Kai · Posted: Thu May 14, 2015 9:56 am Post subject:

Originally, your VW petrol rev counter would have been connected to the coil. You need to find this wire.

The Subaru ecu has a tachometer output, find that. Connected to the VW tachometer wire which would be near the old coil location.

Presumably your aftermarket rev counter is using additional installed wiring?
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DonTPushIt · Force Sensitive Joined: 06 Apr 2015 Posts: 14

Hi Kai,

Yes, the aftermarket rev counter is wired in and working correctly - can I just use this wiring?

Why would this not have been done originally? I think I read somewhere that Richard RJES said he shy's away from it?

Thanks,
Rory

Wilfred · Darth Admin Joined: 13 Nov 2013 Posts: 366

I don't think the VW tachometer will work with the subaru signal. modern engines have entirely different meters. So called air-core meters. The impuls signal is transformed into a current which drives the signal.

The signal also doens't come from the coil anymore (as in the VW) but from the crankshaft position sensor. Different signal
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1973 BayWindow running 1.9 110 bhp TDI with flipped gearbox.

Kai · Posted: Mon May 18, 2015 10:51 am Post subject:

I didn't know that ^^^^^

But if this is the case then my Subaru ecu shouldn't be able to drive my 1985 Porsche 924rev counter....., I don't think the Porsche was running a crank sensor then but then again I could be wrong on that also.

Besides all that, the OP has all the components and only had to swap one wire. No harm in trying is there?
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Wilfred · Darth Admin Joined: 13 Nov 2013 Posts: 366

True! just give it a try.

I recently worked on some tachometers but it could depend on the type and year of car.

Does subare has coil on plug or distributor cap?
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1973 BayWindow running 1.9 110 bhp TDI with flipped gearbox.

Kai · Posted: Mon May 18, 2015 10:59 am Post subject:

Wilfred is correct in his uber technical knowledge.

Read the last post from RJES himself.

http://www.brick-yard.co.uk/forum/ej22-rev-counter_topic41523.html
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andymcc · Posted: Wed May 20, 2015 8:47 pm Post subject:

The dash panels used by VW in later vehicles such as the late-90's Golf and Passat are compatible with the Subaru tach signal. This is one of the reasons I developed my upgrade kit.

HTH
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DonTPushIt · Force Sensitive Joined: 06 Apr 2015 Posts: 14

Purchased a rpm module convertor from RJES. Fitting soon.

mackaymanx · Posted: Thu May 21, 2015 5:24 am Post subject:

There is a mod you can do to the VW tacho to make it compatible with the Subaru tacho signal.

http://www.thesamba.com/vw/forum/viewtopic.php?t=517384&start=323