I bought this really cool super small 10k rpm tach to mount on the dash (no ricer 8" gauge), and I need to know how to wire it up. I know it needs to be set in 4-cyl mode, but I have no idea where to hook up the wires.


Thanks,
Matt

 

for autogage/autometer:

White goes to dash light.
Black is ground.
Connect the following wires to the leading coil (leave stock tach in trailing). If aftermarket tach will not work, that’s an indicator of a bad leading ignitor.
Red (ignition) connect to positive to trigger energize the tach
Green (tach) connect to negative

 

i think I can figure that out.. does the red go to the + terminal on the coil? And the green to the - terminal on the coil? Just want to make sure

Matt

 

Green goes to negative
Red goes to the stock trailing positive

I mounted a 2 1/4 tach outside of my car right where the windshiueld sprayer is located

 

sorry, i was kinda rushing this morning and when i tried to edit, it was tooookkkkkkk forever and I had to leave for field inspection.

yeah you got it right. but the reason why i suggested to connect it to leading due to the following:

1. leave stock tach to trailing...if anything goes wrong with the wiring and the ignitor, the stock tach will not work and that will be a red flag. thats in addition to rough idle.

2. i suggested connecting the aftermarket tach to leading for the same reason as above except it applies to the leading circuit.

now, you got 2 warnings.

 

man i connected mine to wat it said on the manual of my autometre..

it works and all, but it wont go past 1.5k RPMs..

even though my tach reads like 4k for example.... the autometre only goes up to 1.5k and wont go past it!


like its normal up until 1.5k..


when idling..like at 1k.. the tach is very accurate..

its just wont go over 1.5k..
i wonder wats wrong with it? wrong wires maybe?

 

I would check the wiring. The RX-7 tachs use a negative trigger, so the wire that should tell the autometer tach what the RPMs are should be connected to the negative terminal if Im thinking about this properly...

If you have wires that are the same colors as above, thats the correct wiring for the autometer tachs.

~T.J.

 

which colors?

and yeh the manual says connect it to the negative coil anyway..

so yeh thats wat i did..


do i have to cut the wires or sumthing.. someone said shorten it? :?

 

This is probebly a stupid question, but do you have it set for 4 cyl.?

 

help me on this one. since my APEXI tach dont really work on my distributor 13B PP( it will bounce around when it at idile and jump like crazy when I step in gas). so I went out to buy autometer tach and hook just like it said. I even cut wire too. to set the tach as 4cyl. then when I start the engine my car idile at 3000RPM I switch leading to trailing. same thing happend can any one help me here
thanks for ur time

 

Well, doesnt a PP idle high?

~T.J.