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calaisturbo.com.au - Rev Counter circuit to make tacho's work on rb20/25/26 engines

Started by VLRB20DET · 19 May 2004 · 41 replies

Preserved from CalaisTurbo (partial recovery). Original authors and dates are shown; archived members are not current Holdcom accounts.

VLRB20DETArchived member
Alot of people have been asking me for the rev counter circuit to make their tacho's (stock or autometer etc.) work with the RB20/25/26 the circuit is from a New Zealand web site and is in PDF format http://www.gweeds.net/carpage2/RevCounterCircuit.pdf According to the maker of the circuit it works on a RB25DET, and I myself use this same circuit and it works fine with the RB20DET If anyone wants me to make them one please send me a PM ---------------------------------------------------------------
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VLRB20DETArchived member
Oh yeah to the member on here who had a go at me over this circuit, here it is you f u c k i n tool...
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liq11dArchived member
Please check you PM, Thanks
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RyRyArchived member
You dont actually need this circuit. Well i didnt on my vl with an RB20 anyway. All you need is to connect a 10k resistor between pins 7 and 49 on the ecu. Then connect the wire coming from your tachometer to pin 7. Simple, resistor costs 6 cents from **** smiths. Ryan
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VLRB20DETArchived member
ok i stand corrected but all i was told buy a performance mechanic i called was to put the 10k resistor on the ecu tacho wire and connect up the tach wire to the resistor so I went searching for info and that circuit was all i found and i used it and it worked...
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poohkiesArchived member
vlrb20det I spoke to u about this and u abused me, told me i didn't know s h i t!!!! even though it had been done to 2 cars up here, interesting, maybe it's something in the water down there! well u do have a pic of a cow, maybe u just have alittle made cow in u ! f u k i n tool
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VLRB20DETArchived member
yeah whatever poohkies, anyway back when i did the conversion this was the only thing i found that worked, i even put a post on here and on sylinesaustralia and skylinesdownunder and got no reply, but well which ever works use it
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poohkiesArchived member
okies, true! all i did was give my advice on the conversion, as i also have done it and researched it, u bagged the f u k out of what i said! i was just telling you what work, as i have done 2 conversion and assisted a mate on the 3rd, I think the shop is Japaneseautomotive, they sell the wiring diagram form $150, my mates was eaten buy a dog! (no lie) that's where i got my info from,
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VLRB20DETArchived member
no probs phookies, sorry about what i said mate
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John-OArchived member
so whats the go if you are using an aftermarket ecu? i gather the circuit or resister thing wont work, or will it?
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VLRB20DETArchived member
id say the circuit will, as you have a wire that connects to each injector ecu wire so id say that will work with an aftermarket ECU
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komodowagonArchived member
*feels the love*
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VLRB20DETArchived member
Wtf??
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EvanArchived member
how do i do it with a wolf 3d? Evan
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VLRB20DETArchived member
i dont know much about aftermarket ecu's as i dont have one, but id say you would have wires to the ecu for each injector, all you would need to do is put one wire from the converter circuit to each injector wire and then you have one wire to earth and one to +12v and then you have a wire to your tach from the circuit, should work evan..
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EvanArchived member
sounds too complicated for me Evan Some original photos have not been recovered yet.
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brownyArchived member
I know my post is late but I had a couple of things to add that I thought might be useful. 1. Whether a pull-up resistor works can depend on the tacho. Some work, some don't. 2. If you CBF making the circuit above or don't have the skills to do it, Sixworks in Newcastle make and sell neat little "tacho boosters" that will get you out of trouble. There are two types depending on the particular application and are priced at around $50 and $100 respectively. I used the cheaper one which uses the ecu's tacho output so you dont need to splice into injector or coil wires. Installation time ~5-10 min.
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VLRB20DETArchived member
which ever way you go about it, they all work
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JuZiArchived member
evan wot exactly do u want 2 do? i've been told the stock tacho connects straight up to the signal wire (under the bonnet somewhere and straight to the battery, hav i been mislead?
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DEVL25Archived member
The stock tacho will not work with the standard RB25DET (unsure about RB20DET) nor will an aftermarket tacho unless you have the circuit above. I haven't tried with just a resistor covering 2 pins from the ECU.
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