4cyl to 6cyl tacho

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MATT4U
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4cyl to 6cyl tacho

Post by MATT4U »

As most of you know I have a gen1 surf that I have replaced the 2.4td with a 5MGEU

so far I have been using an aftermarket tacho but want the standard dash one to go. I have brought a petrol dash cluster and understand you can add or change a resister on them to change them from 4 to 6 cyl.

any help would be greatly appreaciated.

Matt
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Smurf
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Post by Smurf »

http://www.offroadexpress.co.nz/modules ... ev+counter



I asked the same question a while back, I haven't quite got round to trying it yet though
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wjw
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Post by wjw »

Tachometer- the tach is connected to the igniter by a black wire that can be accessed from the engine harness. The only problem is that the original engine was a 4 cyl, so the tachometer will not read the correct RPMs for the I6. I could have added an aftermarket tach, but I wanted to keep the gauges stock and there really isn't any good location to mount another tach. I knew that 4-Runners also came with a 6 cyl, so I figured there was a way to adjust the tach. Luckily, others who have completed the Chevy 4.3L swap also ran into a similar problem, and have come up with a solution. By adding an adjustable area of resistance (using a potentiometer) between the two tach leads, you can calibrate the tach using a handheld tach. Potentiometers can be picked up for a couple of bucks at any electronics store, and it is simply a matter of soldering their leads to the tach leads. By hooking up a handheld tach to the ignition terminal, and adjusting the potentiometer until the two tachs match up at key RPM points (500, 1000, 2500, etc.), you get to keep the stock tach. It is way cheaper than an aftermarket unit, and looks a lot better also. Oil Pressure gauge- both the Supra and truck wires are Y-B, so it was simply a matter of connecting the two where they exited the wiring harness. Water Temp gauge- same as above, both wires were Y-G 4WD Indicator- as the Supra obviously didn't come with 4WD, I kept the truck connection intact when I removed the harness.


Try this ;) was a write up for a 22RE to 7MGE :-) Two minutes on google..
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Sadam_Husain
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Post by Sadam_Husain »

I went from 6 to 8 cylinders and you need to put a 200 ohm pot in line with the tach wire. dunno if the same maths adds up to go from 4 to 6 cylinders with the same resistance? :scratch:
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