Tach reads double?

[440Chauncey]

I have a stock 440 with a standard electronic ignition conversion kit. I just bough a cheap $25 tach on amazon. Its a 5 wire design. Two to run the light and three to run the tachometer itself. I have the green lead hooked up to the negative side of the coil. After starting it shows double the RPM. I confirmed I had the right settings because this tach has an option for 4-6-8 cylinders. Do I have the green wire connected to the coil wrong? Is there anyway to connect the tach directly to the ECU?

Thanks,

 

[65sporty]

The Neg side of the coil is right, sounds like your cheap tach is bad. If you move the 4-6-8 switch does it change anything?

 

[Turboomni]

Not trying to be rude in any way but really a 25.00 dollar tach? Even if it worked how could you possibly trust it being anywhere accurate? So why bother? My opinion only. ....

 

[440Chauncey]

I agree its a cheap tach, and it changes as i move the different cylinders.

 

[65sporty]

I say the tach is bad.

 

[Turboomni]

I would get your 25 bucks back....

 

[440Chauncey]

yeah, just printed out my return label from amazon!

 

[1978 NYB]

I would get a decent Auto Meter or a Stewart/Warner tach. Look them up on the Summit website and order through AAP or AZ which usually has a 20% off on line offer.

 

[Turboomni]

I ordered through AutoZone online too with the 20% discount. Best deal I could find on Autometer.

 

[70bigblockdodge]

Just practice dividing by 2.

 

[bluefury361]

You have a stock 440. I must be missing something..... The tach is for what....?

 

[Turboomni]

Well I mocked up my tach. Too cold to hook it up and my Fury is down for the winter anyways. [She watches re runs of Highway Patrol in the garage!] I wanted one as I am curious what rpm's on the highway and my speedo is off. The autometer tach is small [2 5/8ths] with no shift lights and alarms and no red line. It will only read only to 6000 which is fine for my stock 440. I tried several times to have the pic posted here as I have many times done in the past but today all I get is in a file. I still have to re position it a bit but you get the idea.

 

[300rag]

Well I mocked up my tach. Too cold to hook it up and my Fury is down for the winter anyways. [She watches re runs of Highway Patrol in the garage!] I wanted one as I am curious what rpm's on the highway and my speedo is off. The autometer tach is small [2 5/8ths] with no shift lights and alarms and no red line. It will only read only to 6000 which is fine for my stock 440. I tried several times to have the pic posted here as I have many times done in the past but today all I get is in a file. I still have to re position it a bit but you get the idea.

Your 5312x2988 picture is too large. I just resized it.

 

[Turboomni]

Hey Thank you rag300! How did you do that?

 

[300rag]

Hey Thank you rag300! How did you do that?

I use this

Image Resizer for Windows

 

[Turboomni]

Thanks again. Downloading it now.

 

[70bigblockdodge]

Hey Thank you rag300! How did you do that?

Buy a crappier camera.

 

[Moparmat2000]

I got a 5" sutometer monster tach with built in shift light and memory recall new in the box i will sell ya. It will be a bit more than the $25 special though lol.