My tach upgrade... in the works

[modular93fox]

Been wanting to get a new dash pad and with that means I need to remove the tach thats mounted through the dash pad.. so I found a tach out of a Mecury Cougar with the 4.6 v8.... mint cluster that I took apart to get the tach out... this is what I ended up with...



Before I took the needle off of the tach, I used some equipment at work that can send a specified voltage at a specififed frequency so I was able to map out various RPM points. After it was mounted, I set the needle back to the OE position.

All I have left to do is scope out the LS tach output and get it to match up with the Mercury tach... and then install in the truck
clint

[bake74]

     Is the blank spot in the bottom for a fuel gauge ?

[beastie_3]

its probably for warning lights

[1979C20]

Its probably like on our trucks with the Brake and Seatbelt indicators maybe?

[modular93fox]

yeah, there are some factory 87 warning lights there... seat belt and something else. I drilled out the rivets on the fuel gauge to remove the gauge part, and likewise to a spare oil psi gauge... just found some tiny screws, and installed the fuel gauge to that. I rubbed off the oil symbol and re installed the needle. Once i get the tach operational, i will put the new fuel gauge where the clock would go.
clint

[modular93fox]

tuned the tach output signal to 4, which is 6 cylinder mode due to the way the tach is currently wired. Read pretty accuratly, but has a dead zone like spot betweeen 1100-1300... no biggie as it reads almost exactly what HPtuners says after that. Good enough for now.