legacycentral bbs

This info may be floating around in a couple threads, but Matt had asked me about it recently, and thought it deserved a thread.

The principle behind the mod is that when you go to a MBC or aftermarket EBC, if you don't leave the BCS plugged in you will get a CEL. Well in comes the dropping resistor. The resistance of the dropping resistor is very similar to that of the BCS, AND on the 90-91 MY's the electrical connector is identical. So you can unplug the BCS and plug in the dropping resistor and avoid a CEL.

The AT dropping resistor mounts to the back side of the turbo sensor bracket and is a good way to clean that area up. For me, I used the resistor when I was running a MBC and mounted it where the BCS used to mount.

http://main.experiencetherave.com/subar ... s/joepmbc/

Here are some pics of the BCS and the dropping resistor & their connectors

http://main.experiencetherave.com/subar ... gresistor/

From what Matt described the electrical connector is different on the 92-94 MY's so you'll need to find one from the 90-91 MY's.

i have 2 dropping resistors in my garage and they both have different plugs an neither of them plug into the bcs plug. i'll get pics tomorrow.

What year are they from?

Its been over a year since I grabbed them... i couldn't tell you.

from my experience at the junkyard today, it seemed to be that the pre-facelift (90-91) had the ROUND connector which is the exact same plug as MY (91 SS) BCS plug. From what I saw, all of the 92+ resistors had a SQUARE connector. It looks to be the same device and all, but the plastic plug is different from my experience. Does the 92+ SS have a round connector for the BCS or square? Meaning that they either changed the engine harness or the BCS plug. I will try to get a pic or two of the different styles since I have a few of each.

The 92+ BCS connector should be round. The harness I got for my ej22t conversion was from a 94 turbo Legacy if my memory serves me correctly.

I am selling a resistor to someone who has a 93 and said it has a "square connector".
Ill send it and if it's the wrong one send him the round one haha. Will update when I find out whats up

That's weird how there are these small discrepencies between the different model years. Silly Subaru

I have a round connector one in my garage (only one i found so far)

So if i have a na car with na harness i will have to wire this along with the map sensor and solenoid to the ecu?

If it has the same connector as the boost control solenoid, then you have no wiring to do, Just plug it in.

CJ,

I think he's asking if he converts his na car to turbo, does he have to run the wiring, and the answer is yes you will need to run the wiring from the BCS, MAP sensor, & pressure exchange solenoid. The MAP sensor is three shield wires, so if you can find a complete MAP sensor wiring setup that would work. For the BCS & pressure exchange solenoid, you only need to run one wire each to the ECU. The other wire is an ignition 12v source which you can add a relay & tap off of another ignition 12v source in the engine bay to trigger the relay if you want. Depending on the ignition 12v source you may be able to just tie directly into it, but I'd make sure you're not overloading anything.