Dakota Dash VHX-67C-PU Tach issue

[flykelley]

Hi Guys
Did a 5.3/460LE swap from a 2000 Chevy pickup to my 69 C-10. The tach on the Dakota reads 2x higher that the tach when I hooked up a scanner to it. It also doesn't appear to be shifting into overdrive. Running about 3000RPM at 60 MPH. I have adjusted the shifter rod. Moved the shirt lever real slow from netural to what I think is overdrive still running high RPM according to the dash Tach. At idling, the scanner shows 678RPM while the dash tach shows about 1250RPM. Has anyone seen this issue? Trying to figure out which one is correct.

Thanks Mike

[dayj1]

Originally Posted by flykelley

Hi Guys
Did a 5.3/460LE swap from a 2000 Chevy pickup to my 69 C-10. The tach on the Dakota reads 2x higher that the tach when I hooked up a scanner to it. It also doesn't appear to be shifting into overdrive. Running about 3000RPM at 60 MPH. I have adjusted the shifter rod. Moved the shirt lever real slow from netural to what I think is overdrive still running high RPM according to the dash Tach. At idling, the scanner shows 678RPM while the dash tach shows about 1250RPM. Has anyone seen this issue? Trying to figure out which one is correct.

Thanks Mike

Can you change the input type on your DD tach? If so, set it to 4 cylinder. By default, thats the signal frequency you will get from a Gen III PCM.

[flykelley]

Originally Posted by dayj1

Can you change the input type on your DD tach? If so, set it to 4 cylinder. By default, thats the signal frequency you will get from a Gen III PCM.

Yes I can change that, will give it a try.

Thanks

[Nodnarb76]

I ran into this when hooking up my DD VHX dash.
Set it to 4 cyl mode and now works fine.

[flykelley]

Hi Guys
Well my stuff is ass backwards. Got into the setup menu and it was set for 4 cylinders. I played with different settings and the 8 cylinder pretty much matches what the scanner is displaying for RPM. Don't understand it but it appears to be working ok. Showing around 2300 RPM at 70 MPH.

Mike