Electrical Stock Tach, Old Swapped 289...

[Honch]

Hay folks,

New member here and would like some input. Recently picked up an '89 LX that has an old carburetted 289 V8 (I've yet to figure out what it's from) and am trying to get the stock tach to cooperate with this engine.

I've since removed the cheap external tach (which Did work fine), and reattached the Dark green / Yellow wire to the wiring harness.

It will register while it cranks, however nothing while running... But after seeing another old thread regarding this (http://www.stangnet.com/mustang-forums/threads/tachometer-only-works-while-cranking.847684), it's apparent that the TPI unit on the EFI distributor is required for it to operate.

Any way to subvert this and get it going?

PS: The coil is an Accel 8410.

Thanks!

 

[jrichker]

The tach signals are completely different between EFI and carb cars. The EFI tach isn't going to work without the TFI distributor. The TFI distributor has no vacuum or mechanical advance, so it does not provide any spark advance when used with a carb setup. That's why most EFI to Carb conversions are road kill engineering.

 

[Honch]

Thanks for the reply bud. Yeah, there is some wiring under the hood that is making me cringe as well... Hmm, so no way outta this situation, aside from reattaching another 3rd party Tach?