How did you get this to work in your car? Do the prongs in the back plug right into the Fiero cluster? I assume the boost gauge is electrical, but couldn't find the sender in the donor car. I'd even send it to you and pay you to modify it. Any help?

The tach and boost gauge have seperate inputs. From memory, the tach input is marked TA and green wire is for the boost gauge.

For power, I believe it's 12V or "IGN" and GND. Those also power the boost gauge. I'll have to looks at one of mine that's out. I ran wires from those three terminals (IGN, GND and TA) to the cooper foil. I also had to trim the right indicator housing. Some people have added bulbs to balance the backlighting but I didn't notice it was needed.

For the boost gauge you need a 2 BAR map from any of the GM turbo cars or SC engines. Unless you are running a 2 bar chip, don't try to replace the stock 1 bar map with the 2 bar map or it won't run right. Use both is necessary and get +5V and GND from the 1 bar map.

Finally, you have to mod the tach circuit to make it adjustable to work on the V6.

With the key on a engine off (and assuming you are near sea level), adjust the yellow CT trimmer to center the boost gauge at 0.
I have some pics and instructions I wrote (somewhere). Email me and I'll send them back to you with the information.

I have the Miller-Woods turbo system that I plan to install in the fall/winter. It uses a 2 BAR MAP and a Computer that accepts it. I have no clue what EMC it uses, but here are the part #'s: Serv. NO. 1226869. Then under that is has 869052 M510841692. Then on another sticker, 16049052. Any clue what it's from?

I live in Utah, around 4000 feet above sea level. Does this boost gauge run off the MAP?

Skitime also has this Sunbird gauge, he may add some insight.

The 6869 is the 85 V6 ECM. Stock for that year.

Sounds like you will have a 2 bar map with the setup so just run a wiring from the output (which also goes to the ECM) to the boost gauge.

Terry