Taco Adjustment - Had a V6 now got a V8

[TWISTY]

I thought I had read somewhere on the internet (classic example of why not to believe everything you read on the net) that most Toyota Taco's have a switch on the back to change between 4cyl and 6 cyl engine. Since installing the Lexus V8 my Taco has only read 2/3 of the actual revs...as it is now getting a 4cyl signal when it is set up to get a 6cyl signal

So I pullled my dash out on the weekend, and found that there is no switch to do as above. But there is what seems like adjustment screws. Has anybody got any info on how to get the taco to work properly by the adjustments at the back of the guages?

Or should I just get a signal convertor and install that??

Heres some pics....

[AIstyle]

My mate had the same problem when he did a 4 to 6 conversion.

His result in the end was either paying big bucks at a pro auto elect place for re-configuration or the easy way which was a monster tacho.

he went for monster tacho and disconnected the factory one.

[ratboy]

jaycar sell just what u need its a pulse ajuster about $45 or iv had taco done for about $90

[RUFF]

I thought I had read somewhere on the internet (classic example of why not to believe everything you read on the net) that most Toyota Taco's have a switch on the back to change between 4cyl and 6 cyl engine. Since installing the Lexus V8 my Taco has only read 2/3 of the actual revs...as it is now getting a 4cyl signal when it is set up to get a 6cyl signal

So I pullled my dash out on the weekend, and found that there is no switch to do as above. But there is what seems like adjustment screws. Has anybody got any info on how to get the taco to work properly by the adjustments at the back of the guages?

Or should I just get a signal convertor and install that??

Heres some pics....

There is defianatly no switch on the dash to simply just switch it from 4-6-8 BUT......

There is a small white potentiometer on the circuit board of the tach. Remove the speedo to gain access to the philips style screw on the little white pot on the board (it points towards the speedo). Then reconnected the instrument cluster (temporarily), started the vehicle, and adjust the pot until the factory toy tach matches the actual RPMs at different key RPMS ie. 2000, 2500, 3000. Obviously you either need a Timming light that has a Tacho read out or borrow a Tacho and hook it up roughly under the bonnet to get it right.

**The above info was found on the internet. I have not done this mod myself.**

[V8 Middy]

jaycar sell just what u need its a pulse ajuster about $45 or iv had taco done for about $90

The Jaycar kit is designed for speedo correction but with some basic electronic know how it could be adapted for this.

Ratboy, where did you get yours done? I was quoted $160 by ringwood speedometer service but that was to adapt from diesel to petrol tacho

[mico]

I thought I had read somewhere on the internet (classic example of why not to believe everything you read on the net) that most Toyota Taco's have a switch on the back to change between 4cyl and 6 cyl engine. Since installing the Lexus V8 my Taco has only read 2/3 of the actual revs...as it is now getting a 4cyl signal when it is set up to get a 6cyl signal

So I pullled my dash out on the weekend, and found that there is no switch to do as above. But there is what seems like adjustment screws. Has anybody got any info on how to get the taco to work properly by the adjustments at the back of the guages?

Or should I just get a signal convertor and install that??

Heres some pics....

There is defianatly no switch on the dash to simply just switch it from 4-6-8 BUT......

There is a small white potentiometer on the circuit board of the tach. Remove the speedo to gain access to the philips style screw on the little white pot on the board (it points towards the speedo). Then reconnected the instrument cluster (temporarily), started the vehicle, and adjust the pot until the factory toy tach matches the actual RPMs at different key RPMS ie. 2000, 2500, 3000. Obviously you either need a Timming light that has a Tacho read out or borrow a Tacho and hook it up roughly under the bonnet to get it right.

**The above info was found on the internet. I have not done this mod myself.**

if you pull the taco assembly off the cluster you will see the little white adjuster screw it is difinetely the taco adjustment, mine was just done if you can plug your taco into a 4cyl with a single igniter and tune it to that it should be alright, the bloke that did mine did it in about 3mins and was pretty easy

cheers
mico

[TWISTY]

There is defianatly no switch on the dash to simply just switch it from 4-6-8 BUT......

There is a small white potentiometer on the circuit board of the tach. Remove the speedo to gain access to the philips style screw on the little white pot on the board (it points towards the speedo). Then reconnected the instrument cluster (temporarily), started the vehicle, and adjust the pot until the factory toy tach matches the actual RPMs at different key RPMS ie. 2000, 2500, 3000. Obviously you either need a Timming light that has a Tacho read out or borrow a Tacho and hook it up roughly under the bonnet to get it right.

**The above info was found on the internet. I have not done this mod myself.**

Cool, thanks Tony....I didn't even think to do a search....and quickly found the site you copied it from by doing so....whoops.

Here is the site for anyone else who is interested......
http://www.mindspring.com/~jayk3/toyota/tachmod.htm

I have found the pot on the taco and just need to get the speedo out, and another Taco to use to calibrate it and I'll be underway.

I'll do a write up on this thread of how it all goes with pics.

[ratboy]

jaycar sell just what u need its a pulse ajuster about $45 or iv had taco done for about $90

The Jaycar kit is designed for speedo correction but with some basic electronic know how it could be adapted for this.

Ratboy, where did you get yours done? I was quoted $160 by ringwood speedometer service but that was to adapt from diesel to petrol tacho

mine was done through a auto elect called (j.o.b) i know thay sent it away to have it done some where in melb

[HG]

I have a Monster tacho mounted in front of the original tacho as well as temp & oil pressure gauges. I went the easy way (looks tough too) when I figure out how to post up pics I'll put some on here.