Alright, I'm still rewiring alot of stuff here and the tach would be nice to have.
I've measured about 12.9-13.5 Vdc on the distributor connection labeled TACH.
I'm sure this is where I connect the TACH to...kinda makes sense...BUT
where do I connect it to?
I've removed my ECM and not sure exactly which wire under my dash is the appropriate one.
Is it normal to see this type Voltage setting for a tach output?
I can provide pictures of what I'm talking about if someone has a clue what I'm talking about here.
Just in case it isn't clear, I'm running a Holley 600 carb on a HEI ignition system here.

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Duffster (age 31)
BEAT DOWN HARD 88' Camaro Sport Coupe,
1978 Caprice Classic 305 motor havin'(WITH NO COMPUTER),84' 700R4 Tranny usin', 84' Z-28 Nose clip wearin',
84' Z-28 Hood covered,
AND THE TIRES:
245/60-16 Firehawk SS20 on Firbird rim(1-passenger rear),
235/55-15 BF Goodrich's on CompTA's on Z28 rims(2-on front),
235/60-16 Pirelli P600 w/a curb check or 3 also on Firebird rim(1-drivers rear),
REAR HATCH MASTER OF ALL!!!
Duffster_Camaro@HOTMAIL.COM
Owner of the Camaro 0 out of 10 Third-genners approve of, no longer part of the non-existent Iowa crew.

 

With the ign on & the engine not running, there should be 12 volts at the tach lead. It will pulse between 12 volts & ground, when the engine is running & should have no voltage to it when the ign is off. The tach connection at the coil is really the output of the EST module in the distributor that switches the coil on & off - the other connection to the coil is +12 volt ign power. The tach wire goes through the fire wall at the connector on the driver's side & routes to the instrument cluster only. It does not go to the ECM.

Tim

 

since i'm going to be routing this fresh, which wire in the cluster is the tach wire i should connect with?

 

The tach input to the cluster is normally a white wire & connects to pin 11 of connector C1. The tach power wire to the cluster is a pink / black wire & connects to pin 10 of connector C1 - this wire should already be in place, as it powers the oil pressure gauge & the speed sender, as well. The tach ground wire to the cluster is a black wire & connects to pin 9 of C2 - this wire should already be in place, as it grounds lots of other stuff in the cluster, as well.

The pinout of the C1 & C2 connectors, as wiewed from the connector contact end, are as follows:

14,13,12,11,10,9,8
1 ,2, 3, 4, 5, 6,7


Tim

 

guess i could have updated earlier Tim.
after i blew a fuse to the wrong white wire, and replaced it after finding proper white wire,(both C1 and C2 have white wire in slot 11), I HAVE TACH!!!
THANK YOU! ! !

[This message has been edited by Duffster (edited October 15, 2000).]

 

Bummer about the fuse! Which fuse blew & what year harness is it?......Glad you got the tach going!

Tim