TBI gauge compatibility

[MtBraun]

Will my TBI sending units work with the old style gauges? I read somewhere there may be an ohm rating difference, but can't find the specifics. I'm thinking about hooking up oil pressure, tach, and coolant temp directly from the installed TBI sending units. If the old stock 78 gauges won't work, what updated gauges will work in the stock gauge cluster?

Thanks.

 

[RustyPile]

You left out some information, unknowingly probably. Is your "engine management system" computer driven? Exactly what engine and fuel delivery system do you have?? Are engine mounted sending units required, or, are they just in place to "plug a hole"?? I just went through a similar situation.. I recently purchased an 83 "square body" with a modern engine that has been "retro-fitted" with carburation instead of F.I. Temperature sending units prior to 1980 have different resistance to ones of a later date.. I'd suggest you incorporate sending units that are specific to the factory gauges.. If your instrument cluster is original '78, then, with the exception of the fuel gauge sending unit, you should install '78 sending units...

 

[MtBraun]

Sorry for leaving out that info. I am finishing a TBI conversion on a gen 1 350 with th350 in this 78. I thought I could use the TBI sending units for my old gauges, or figure out what gauges would work with the updated sending units. I was hoping to not run dual sending units (one for gauges, one for TBI).

My gauge cluster is in need of a refresh, so maybe that's my answer!

Thanks.

 

[1987 GMC Jimmy]

I agree with Nick. The resistance ranges are definitely gonna be different on the coolant temp sender, and I just checked part numbers for the oil pressure gauge senders, and they had different numbers so same deal just to be safe. Fuel is gonna be the same. Spend a few dollars, and your gauges should be guaranteed to work. I'll tell you from personal experience that coolant temp senders are hit or miss, even if you get what you're supposed to. Make sure they don't give you the one for an idiot light, and you should be off to a good start.