Center Tach Conversion problems

[homeworld1031tx]

Hey guys need help with the center tach
it was working fine for the lst few months but i took it out to install new LEDs and when i tried to recalibrate the gauges, the tach would always rest at 0 when idling (or around there) not matter what point i set the calibration at (like started it from on the reverse side of the stopper)..any ideas as to what could be causing it? thanks for the help

[Jesse IL]

Check all your solder connections on the rear of the board. Those solid-core wires are very difficult to solder and I had two pop off.

[homeworld1031tx]

Check all your solder connections on the rear of the board. Those solid-core wires are very difficult to solder and I had two pop off.

right after i wrote this up i went through and resoldered everything, still no luck :(... so i think what im going to do is just have the car on and set the gauge at like 1000 rpm cause thats what it idles at when warm if i remember correctly....is that true?


edit: alright new question....got the tach working-ish, but not sure about the speedo and wont be able to match someone till the weekend so i just wanna see if i can do it like this
can someone write down all the speeds for a GT-S in each gear at 3000RPM or so?
thanks a bunch

[LEDmod]

Is the needle not moving or moving weird?? if it is them.. probably the solder connecting is lose or came off....

If the calibration is the issues then follow this guide..

http://i21.photobucket.com/albums/b284/seanyiya/Gauge%20Face/Custom/Calibration/CENT-Needle_Calibration.jpg

[Jesse IL]

I should also ask you what instructions you followed? The ones that Dooly provides with the gauge or the ones that are posted on this site?

If you compare them, they are dramatically different. I used the ones on here and ignored the instructions Dooly sent.

[S|Lv3rBu||et]

I should also ask you what instructions you followed? ... I used the ones on here and ignored the instructions Dooly sent.


I did the opposite and both needles are far more accurate now than when I used the other method.

[Jesse IL]

I did the opposite and both needles are far more accurate now than when I used the other method.

The fact that he provides two completely different sets of instructions is really kind of troublesome. Quality Control at its finest...

[gt-s688]

my tachometer responds very slow.. i cut the circuit board over and over again and still have the same problem.. and its been a while, could it be the wires then?

[LEDmod]

my tachometer responds very slow.. i cut the circuit board over and over again and still have the same problem.. and its been a while, could it be the wires then?

Show me the picture of how you did the circuit board and I can diagnose it...

[LEDmod]

I did the opposite and both needles are far more accurate now than when I used the other method.

The fact that he provides two completely different sets of instructions is really kind of troublesome. Quality Control at its finest...

I've made some improvement over the instruction and have two set (one for stock layout and one for center tach conversion)
All the instruction is pretty much has same basic idea of calibrating the needle

I've made some improvement over many things since the older gauge face production days....

[Jesse IL]

I've made some improvement over the instruction and have two set (one for stock layout and one for center tach conversion)
All the instruction is pretty much has same basic idea of calibrating the needle

I've made some improvement over many things since the older gauge face production days....

You sent out one set of instructions on how to rewire for the center tach.

On this website you have a completely different set of instructions.

Which one is right?

[LightningRod]

In case it was overlooked:

Make sure the needles aren't pressed down too tight.

The first time I worked on my cluster, that's exactly what I did and it freaked me out. I was real disappointed thinking that I might have seriously fcuked something up. Turned out to be a false alarm.

[LEDmod]

You sent out one set of instructions on how to rewire for the center tach.

On this website you have a completely different set of instructions.

Which one is right?
Ohh..
You are talking about this one..
http://newcelica.org/forums/showthread.php?t=205567

The printed version and guide here has same result..
Printed version is summary of the conversion..
Online version is step by step guide(with lots of pictures) for people who have difficulty understanding the printed version..
If I print all the steps from the online version.. then it will be way too many...
Color prints aren't cheap....

They look different but online version just have more details and more pictures.. that's all.....

[Jesse IL]

They look different but online version just have more details and more pictures.. that's all.....

No, that isn't the difference. They have you solder wires to completely different locations. I'll make a scan of this and post the pictures side-by-side if you'd like.

[LEDmod]

No, that isn't the difference. They have you solder wires to completely different locations. I'll make a scan of this and post the pictures side-by-side if you'd like.

If you are talking about the show actual picture of the wires... yes.. that is different...
I've put that actual picture as reference and showing move the wires so that wires don't get crushed...

All the guide will have same result....
Soldering points might vary, but either way works...

[homeworld1031tx]

alright well i got the tach and speedo working a while ago, but the speedo is drastically different from what i had it set at b4 (b4 i put the LEDs [ie b4 this weekend] at 2000 rpm in 5th i would be doing around 40mph. now to do 40 mph in 5th im at about 2500)
SO my question still stands. if anyone knows any RPM/speed combos, please post 'em up (preferably speeds in each gear at 3000 RPM).

Jesse, I used the instructions that he posted on this site ( for the center tach i placed the needle so it was basically touching the stopper and then gave it a counter clockwise turn, for the speedo i tried to put it on the tip of the light icon but not sure i hit it correctly so this is why i am asking, to make sure they are good.

[homeworld1031tx]

ttt....i really need this info guys...if someone even just had the gear + final drive ratios that would be all i need

[LEDmod]

If you know how much it's off, just move the needle back how much it's different and push the needle back in...

[homeworld1031tx]

yea that is what i was planning on doing but as of right now i still don't know how much its off :-/

[LEDmod]

2000 rpm in 5th i would be doing around 40mph. now to do 40 mph in 5th im at about 2500

Check your idle with engine fulled warmed up..
Needle should be around 700-800 rpm

[LEDmod]

If you want to calibrate the needle by gear matching...
You need at least one side has to be accurate....

[homeworld1031tx]

Check your idle with engine fulled warmed up..
Needle should be around 700-800 rpm


k thats a good one too...i figured all cars idled differently but if you are sure that all 2zzs idle warm at 700-800 then my assumption that i was 200 off (by seeing that it bounces off the rev limiter at 7200 now) is right...i idle at 1000ish when warm.

anyways. my request for gearing still stands :wiggle:

[homeworld1031tx]

k thats a good one too...i figured all cars idled differently but if you are sure that all 2zzs idle warm at 700-800 then my assumption that i was 200 off (by seeing that it bounces off the rev limiter at 7200 now) is right...i idle at 1000ish when warm.

anyways. my request for gearing still stands :wiggle:


edit: never mind found them
future search reference
CELICA GT-S GEAR RATIOS
1st 3.166
2nd 2.050
3rd 1.481
4th 1.166
5th 0.916
6th 0.725
Reverse 3.250
Final Drive 4.529

[LEDmod]

k thats a good one too...i figured all cars idled differently but if you are sure that all 2zzs idle warm at 700-800 then my assumption that i was 200 off (by seeing that it bounces off the rev limiter at 7200 now) is right...i idle at 1000ish when warm.

anyways. my request for gearing still stands :wiggle:
From the Toyota Celica service manual..
It said 700-800 rpm idle...

[homeworld1031tx]

i did some calculations and got 36 mph in 5th gear at 2000 rpm. sound right? thats with 18 inch rims on 225/40s

[gt-s688]

Can the conversion be reversed?

[LEDmod]

Yup, it's very simple to reverse it..

[gt-s688]

can you please tell me how?
do i need to replace the cut copper?

[robare99]

Just unsolder the wires, and put a drop of solder between the parts you cut, isolating the pin. It will just join it all back together. Good as new.