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I completely removed the na 33k resistor, and replaced it with a 52k resistor. That's all I did and the tach is exactly correct now.
Ok, I have done the GE to GTE conversion, please don't be a cheapskate and use a patch wire. Buy the required resistor in case you get a spike in power!

This is my NA tacho, see the blue resistor? That is all you need!!!

guys, thank you. you just gave me the info i was seeking for a long time. thanks again. will try it and let you know of the results. (btw my engine swap is a JDM on USDM car, will the fix work regardless?)
 

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Sorry to bring this old post back up. But was wondering..I have a USDM 6-speed harness and an Aristo motor..but a N/A tach. Is ^^ this what I need done to make my tach work again? Get a 52k resistor and solder it on my N/A USDM 5-spd tach?
 

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remove the 33k one (three orange strips) and replace it with the 52k one.

I bought a 51K because that's what they had at my local electronic store. I was planning to confirm that guy once I got my engine running.
 

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remove the 33k one (three orange strips) and replace it with the 52k one.

I bought a 51K because that's what they had at my local electronic store. I was planning to confirm that guy once I got my engine running.
Which resistor is it? The big blue one? or the small one in front or the smaller one behind it?
 

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The one to the right (small one in front of the smaller one).
 

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On my NA-TT, I did the 33k Resistor bypass but I didn't need to do the Igniter wiring mod.

It worked fine.
Same here.
 

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Im doing the gte swap using aem and tt harness, do i still have to go through this ?
I'm wondering the same thing. I have a NA 5spd that I'm doing a full GTE swap and running AEM V1. Will my NA tach work or does the AEM V1 send out the same signal as the GTE ECU and still have to do the 52K resistor swap?
 

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The stock configuration for tach on the non VVT-i engines is tach signal from the igniter so you'd need to do the resistor swap. BTW I measured it myself and got 51K, not 52k, coincidentally exactly what I bought before I even measured. I'm sure you can setup the AEM EMS to output a GE tach signal.
 

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Just picked up the 51k resistors today. They were only $1.50 for a 4pk at my local electronics store. Way cheaper than buying a $400 dollar TRD Tach that does the same thing as the NA one. I was wondering, is the resistor on the tach a 1/4W or a 1/2W? I didnt know which it was so I picked up both. Just wondering which one I actually need? Im guessing the 1/2W judging by the size in the posted pic.
 

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I tried the 51k resistor mod but it didn't work, I was going to just jump it completely but tried a 16k instead and that worked fine, looks to read accurately. I'm a JDM 6-speed SZ-R to JDM supra TT motor, didn't think that would make a difference but maybe it does.
 

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interesting information, and just wanted to check this out. found:

NA resistor color code: yellow, orange, orange = 43k
TT resistor color code : red , yellow, orange = 24k

FYI - visually inspected and confirmed with the ohm meter andthen found it to be within that range
 

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interesting information, and just wanted to check this out. found:

NA resistor color code: yellow, orange, orange = 43k
TT resistor color code : red , yellow, orange = 24k

FYI - visually inspected and confirmed with the ohm meter andthen found it to be within that range
My Setup:
1993 NA 5spd
2JZ-GTE Engine
'97 OBD-II US-Spec 2JZ-GTE Engine Harness
AEM V1 EMS

Tonights results:
1) I removed the stock NA tach resistor and replaced it with the 51K resistor but tach still did not work.
2) I removed the 51K and just jumped it completely with a small piece of wire. Tack appears to work correctly BUT...
I compared it to the signal my AEM is receiving. At idle it appears ok, +/-100rpm. using my 2step set for 4,000rpm, the tach and AEM read the same at 4100-4200rpm. However when i gradually climb in rpm's from idle to 2,200 rpm the Tach reads less than the AEM. at tach speed (2200rpm) my AEM reads 2,600.

From what I understand, My tach is not getting a strong enough signal. No resistor is needed. In reality, it seems like it could use even less resistance/stronger signal. But I don't know how to do that when I already jumped it, other than to boost the signal somehow. Anybody got any thoughts or opinions on this? Anyone else have this same issue on their car?

EDIT:

100ohm (the blue thing is a 100 ohm metal film resistor 1/4 watt) parallel resistance that will drop the tacho series resistance to close to 100ohm which gives a suitably high signal for the tacho to register. I used a piece of wire and welded it and works fine.
Just found this on Club NA-T. Anyone tried this 100ohm resistor mod?
 

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had a spare NA tach....So I went to Radio shack and bought the only one closest to 24k, a 22k, replaced the 43k NA resistor and worked great. but could not compare to known source. btw, from what I remember, by jumping that NA resistor, voltage is being divided between the 43k and jumper,ohms law anyone? E=IxR
 

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had a spare NA tach....So I went to Radio shack and bought the only one closest to 24k, a 22k, replaced the 43k NA resistor and worked great. but could not compare to known source. btw, from what I remember, by jumping that NA resistor, voltage is being divided between the 43k and jumper,ohms law anyone? E=IxR
I had removed the stock NA resistor completely when I did the jumper mod. Im not a physics major, but just assuming that everything takes the path of least resistance, it wouldnt matter whether it had a resistor or not. Anyone with an education have some input on this? LOL
 

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I had removed the stock NA resistor completely when I did the jumper mod. Im not a physics major, but just assuming that everything takes the path of least resistance, it wouldnt matter whether it had a resistor or not. Anyone with an education have some input on this? LOL
You are correct.
 

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when you examine the two photos, they are both jumping to different places, why is that?

the tach with the red wire is jumping to a different area than the tach with the blue resistor?
 
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