For all you NA tach users...

[aphxero]

Okay so 7mge tach will work fine with 1j the difference is just frequency. You have to hook up the black wire from igniter which is IG- on the diag box and same on the tach.

So go take your tach out and on the screw hole where ig- signal enters the tach look for the first resistor once it hits the board. Should be a 30Kohm. Cut it off leaving a little of the leads. Then solder a small piece of wire in where the resistor was. I've verified against an safc2 and also dynojet and it's dead on all the way to 8krpm.

Put tach together and go rock out!

:)

PS: this works with 2jz also.

[SupraMario]

Okay so 7mge tach will work fine with 1j the difference is just frequency. You have to hook up the black wire from igniter which is IG- on the diag box and same on the tach.

So go take your tach out and on the screw hole where ig- signal enters the tach look for the first resistor once it hits the board. Should be a 30Kohm. Cut it off leaving a little of the leads. Then solder a small piece of wire in where the resistor was. I've verified against an safc2 and also dynojet and it's dead on all the way to 8krpm.

Put tach together and go rock out!

:)

PS: this works with 2jz also.

Really???
Hmm, well I already have the dakoda decoder thing from Dr. Tweak and tonight I realized that I am 10-11mph off and I dunno about RPM, I think it is fine as I idle around 550-650rpm.

[tlo86]

Really???
Hmm, well I already have the dakoda decoder thing from Dr. Tweak and tonight I realized that I am 10-11mph off and I dunno about RPM, I think it is fine as I idle around 550-650rpm.


you have to set it so it knows you have 6 cylinders and not 8 or it will look like you redline at like 5krpm

[86_sports_1jz]

nice i wished this would have came up earlier could have saved 100 bucks

[SupraMario]

you have to set it so it knows you have 6 cylinders and not 8 or it will look like you redline at like 5krpm


LOL yea i know I still haven't set it yet:biglaugh:

[87soup]

Im soo down!!!
I have a 1JZ- N/A set up and i havnt had a tach for about 9 months!!!
Im hecka intimidated to take the stock tach out though...
Can any one coach me through it or send me into a write up or something???
I really am interested in this!!!

Thanks SM!!!

[chuckmuska2005]

Yes, very interested on a write up! Anybody have details on this?

[YotaRob]

I did this and it works, there is a website about this. I will post a link when I get home. Or google 1jz tach fix and it shows up I think. Its a good article on all the tachs, na has 30k resistor 7mT has 130k I think and 1j has 100k.

[YotaRob]

found it on google: http://www.autosoftsys.com/supra/tachcompare/

[suspectsupra]

will this work with the 2jz swap....

[YotaRob]

It should as they both use the same igniter

[suspectsupra]

does anyone have pictures of this

[OneJSupra]

will this work with the 2jz swap....

I don't see why it won't since the 1jz and 2jz use the same igniter. How's the 2j man and when we're going to OSW? HAHAHA, yota beat me to it.

[suspectsupra]

I don't see why it won't since the 1jz and 2jz use the same igniter. How's the 2j man and when we're going to OSW? HAHAHA, yota beat me to it.

we should setup up something....my twins are starting to give out....single soon...

[ronnie4]

I did this and it works, there is a website about this. I will post a link when I get home. Or google 1jz tach fix and it shows up I think. Its a good article on all the tachs, na has 30k resistor 7mT has 130k I think and 1j has 100k.

Shouldn't we solder a 100K resistor in instead of just shorting the leads then?

[aphxero]

I've checked mine against my dyno and my safc and it's right on. If you're a little off maybe you could use a 100k pot to tune it? It seems the other resistors and things don't have much of an effect on the readout (if any).

Try it out I'm sure it'll work out fine :) Even if some of us end up being 5-10 rpm off who cares. Tach isn't life and death right? I don't know about you guys but I don't look at it a whole lot. Funyy how it's super annoying when it doesn't work haha.

[ronnie4]

I've checked mine against my dyno and my safc and it's right on. If you're a little off maybe you could use a 100k pot to tune it? It seems the other resistors and things don't have much of an effect on the readout (if any).

Try it out I'm sure it'll work out fine :) Even if some of us end up being 5-10 rpm off who cares. Tach isn't life and death right? I don't know about you guys but I don't look at it a whole lot. Funyy how it's super annoying when it doesn't work haha.

Thanks for your help, will probably do this mod this weekend.

[ronnie4]

Which resistor on the picture below did you cut? R1?

Also where did you get the ign- from? Straight from the igniter?

Thanks

[terror]

where exactly is this ig- wire at, i cant seen to find it a picture would be great

[aphxero]

That would be r4. The one directly connected to the signal input.

And yes ig- from igniter.

[ronnie4]

Id like to know which wire is ig- as well before I start cutting wires, the connector on the left has a black wire black, that the one I splice off of?

[aphxero]

yeah it should be that one. Check continuity to the ig- pin in the diag box.

[ronnie4]

Finally got around to doing this mod today. Works great for me as well, thanks for your help.

[terror]

wait so let me get this staight, after you replace resistor you have to splice off of the ig wire and run it through the firewall onto the tach?

[ronnie4]

wait so let me get this staight, after you replace resistor you have to splice off of the ig wire and run it through the firewall onto the tach?

That is correct

[terror]

ok, so i go around to doing this and it worked great first time i tried it but as soon as the car warms up and the fan kicks in the tach starts to jiggle like crazy then dies soon after, any ideas?

[aphxero]

Too many variables to tell. is your fan it's own independent system?

[Jacob]

of course I read this after I send payment for a GTE tach circuit

[aphxero]

Hey man It's been on jzxp for a month.

[terror]

yes it is, also wouldnt attaching the ign- on the tach to the ig- spot on the diag box work?

[ronnie4]

yes it is, also wouldnt attaching the ign- on the tach to the ig- spot on the diag box work?

It should, doesn't matter where you get the ig- signal from.

[aphxero]

Do you have noise damper on the ignition circuit? I know it shouldn't matter but it might.

Also, what's your power source for the fans? Also what's the power source for the coil side of the relay?

I'll bet it's +b1 (efi relay). Try ACC instead. It'll kick off when you're cranking too. Better starting :)

[terror]

what relay are you taking about? where is acc, the fans are connected to an empty spot on the fuse box and im not sure if theres a noise dampener on or not thanks

[aphxero]

Well if youre pulling voltage directly from the fuse box it's more than likely +B which could def interfere with the ignition. And the noise dampener is next to the igniter small grey square thing.

You should probably get a relay on that guy and quick. The battery makes an excellent source for a fans power supply.

If you don't have a relay try using the stock ac condenser fan circuit for it. Just get that huge draw off of +b that's a seriously bad idea.


Thanks.

[RockPaperSwoRD]

I just tried it and it worked! running 1jz on 7mge tach. I didnt have to run any extra wire or anything either, I had already matched the tach signal when i did my 1jz harness ^_^