What is involved in using a 3 Bar Map

[Rebel Rob]

Like the heading states.. what all is involved in using a 3 bar... is there a how to some where... step by step cause I'm rather new to putting these together... and are they worth it I want to run a stage 4 comp from FWD or maybe one from turbos unleased and to run the one from cindy it says that a 3 Bar Map sensor and +40's i was planning on using the +40's.... so please let me know?? thanks.. Rob

[turbovanman²]

I don't understand your question, sort of. If the cal requires a 3bar map, you have to run it. It lets the computer add fuel to 3 bar, which is around 29 psi. To install, you modify the map plug slightly and thats it. A 3bar cal won't run with a 2 bar map and vice versa as the vacuum to voltage tables are shifted.

[Marcus86GLHS]

You'll need (3) things to start:

1. a 3 bar calibration (computer), available from TU, FWD Perf., and others
2. a 3 bar MAP sensor (available from same vendors or from Summit, etc)
3. a 3 bar MAP connector to go from your new computer to your new MAP sensor

example (this is for an omni so your cal/install of course will be different but same general concept applies to any 2 bar to 3 bar conversions):

here's the stock logic module from a turbo omni on the left, with the stock 2 bar MAP sensor removed from the computer (that square opening) showing the stock 2 bar MAP connector. on the right is a new 3 bar MAP connector that will have to replace the 2 bar connector on the left:
http://memimage.cardomain.net/member_images/8/web/632000-632999/632619_204_full.jpg

next i sent out the computer to my vendor (Turbos Unleashed) with the connector, the custom calibration is then done by the vendor and that 3 bar MAP connector is spliced onto the new logic module.

then its just a matter of installing your new 3 bar MAP sensor somewhere near your new computer so that you can plug the new calibration into the new MAP sensor using that new plug, here's a pix of the new cal installed in an omni, that black conduit is the wiring going up to the 3 bar MAP sensor (not shown)which has been velcroed under the dash (this install was done in this manner to keep the car looking stock but i could have installed the 3 bar MAP sensor underhood and routed new wires to it there).
http://memimage.cardomain.net/member_images/8/web/632000-632999/632619_110_full.jpg

of course your new MAP sensor also receives the same vacuum/manifold pressure signal from the engine via tubing, just like on your 2 bar sensor so that switch-over is very simple.

hope this helped.

[Rebel Rob]

yes it did thanks

[turbovanman²]

Keep forgetting and Marcus pointed it out, durrr. All cars/vans except L bodies and TIII R/T's, you can modify the stock connector with a knife. The other ones need the proper Map connectors installed.

[inmyshadow]

This statemnt also applies to 91+ turbo cars.

I had to convert my 91 MAP connector to a 90 connector. I also used a brand new GM weather pack connector with my 3 bar map.

Now I can easily convert back to stock since both maps share the same connector now.



Keep forgetting and Marcus pointed it out, durrr. All cars/vans except L bodies and TIII R/T's, you can modify the stock connector with a knife. The other ones need the proper Map connectors installed.