82 C10 EFI Conversion project

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82SquareBurb

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Thanks Count! Yeah I reached out to Holley and Current performance. I guess the universal MPFI harnesses don't use the standard LS style MAP connector, so I need to adapt from the Delphi weather-pack connector to the GM MAP sensor. It's always something! :doh2:

I also ordered up some 3-pin connectors, so worst case I wind up making my own pigtail adapter. One connector holding me up at this point. So frustrating.
 

82SquareBurb

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So far everything is buttoned up, fuel, wiring, most relays, and having connector fun now.

For anyone that might be doing the same swap:
Some fun facts about the Holley "universal MPFI term x max" Holley kit: #550-942 and specifically the universal Harness: 558-104.

The MAP sensor connector on this unit is an odd 3-position weather-pack "green" connector, which only plugs into older 1bar sensors - and no adapters exist as there seems to be no mating female pin connector on earth for the green connector, without modifying some 3-way WP connector to fit. Hence my mismatch above. So running a 3bar MAP requires repining the holley 570-212 connector with an 13519049 - Delphi GT 150 3 Way (or holley's 570-217) to mate to the adapter, or just re-pin a new aptiv/delphi metri-pack connector to plug directly into the sensor.

Also the IAC connector is wired for a Mopar/Holley IAC motor out of the box. To run it with a GM IAC unit, need to swap pins A and C for proper idle control.


Holleys illustration:
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So aside from those curveballs, it's been almost plug and play, minus needing the EV14 injector harness and a couple adapters. Fun fun!
 

CountKrunk

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v8 350
aside from rewiring the plug, repining the IAC, an entire wire harness, and some adapters you can install it right out of the box!

haha
 

82SquareBurb

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Holley should just rename it the "Close enough kit" :33: I thought for sure Holley would offer an $85 adapter (made out of $2.50 in components) I could duplicate, but nope. Just cut it off is the solution. So be it! lol
 

82SquareBurb

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Just got a reply from Holley, here is the reply: "Use the LS3 Adapter Harness. It will Plug in." So a new connector it is!
 

NLD79K10

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I've never experienced a "universal EFI harness" to actually be universal, everything I've installed over the years needed some form of modification to tie into an injector set, sensor or IACV.
 

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