RomRaider

I am new to all of this but am looking for a way to tune for an atmospheric bov instead of the stock one...where should I start and would I be able to tune to where it doesn't go way rich upon shift? Also I am looking at the c00b stg 2 91oct map but I am going to tweek it for 93oct what are the big differences for this, would i basically need to adjust the timing and do logs until I get to the point where I want?

Not sure if you can do anything about the BOV. The reason you run rich is because that air you are venting to atmosphere was metered by the MAF and is expected in the combustion chamber. You could switch to a recirculating BOV or the stock BPV and not have any problems. If you have to have a BOV for "the sound" then go with a 50/50.

As far as tuning for 93 octane, it would be safest to change the values in the ignition correction map, as opposed to the base ignition. That way, the ECU can drop your timing across the board if it sees major detonation by dropping the IAM down quick (say, you got bad tank of gas). You need to do a lot of logging and look at your timing, knock correction, load and rpm and figure out where the ECU is running full ignition correction consistently and then gradually raise those values and test for logging. Keep an eye on your IAM (ignition advance multiplier). If it isn't 16 before tuning the 91 map, then your ECU is already seeing detonation, even with your 93 octane gas, so you need to take care of that first before advancing timing.

I've thought about the BOV and basically we'll have to do some reprogramming of the ECU to compensate for one. I'm not sure how easy or hard it'll be but I'd guess eventually we'll be able to do it.

That would be cool!!!!@

Yeah, that would be a nice otption. I don't see a way to program for a BOV seeing how it's placed after the MAF sensor. On mine, it pops (after-fires) on most shifts. Of course I'm catless with a single straight through rear section. I wish I would've placed the BOV before the MAF sensor but at the time I wasn't set up as a blow through arrangement.

We would actually need to change the logic that adds the bypassed air to the MAF readings so the car isn't expecting that rush of air from the the BPV.

Thanks for the reply. with the bov ill try thinking of something to accomidate that. now for the 93 oct tuning, I just got a qtec DP with the electric cut out, I just cant wait to get it installed and do some tuning with it. I love living in florida when the only time you have to watch your cars noise is pulling into the neighborhood is there anyone else on here that lives in the sarasota area?

The problem is you are releasing air that is already metered and expected to be in the system. Without having another flow sensor, I don't think you can compensate for a BOV using MAF-based logic.

If you were to use MAP-based maps, then that would be another story. Of course, then you wouldn't have compensation for different conditions (temperature, humidity, altitude, etc).


Mike

How would you/could you tune using this software for a map setup instead of a maf setup? also would it be worth the extra efforts?

You can't using this software currently. You would have to get a standalone ECU that was MAP based, but it definitely would not be worth it just to tune for a BOV. I would go with a recirculating BOV or a 50/50.

well, not speaking in purly a bov standpoint would switching to a map based ems yeild better power/drivability then using a maf based programing?

You'll gain power where the MAF setup becomes a restriciton in the intake. I don't think that is worth it for the average WRX setup. I'm not an expert on the standalones, though, so maybe someone can chime in here. As far as driveability, MAF is the best.

maf set ups are definately a better choice for drivability. and really i can't see what the big deal is with tuning for an atmosphere BOV, im running a 50mm Tial and its on the stock ecu flash. it only goes rich for a split second and i don;t know about you, but i never have any stalling problems. also if it doesn't go way rich when you shift at high rpms you may start running into shift knock, but in that case you just put the ignition timing down to like 20 or so at those points in the low load column.

I had an atmo bov installed for a few weeks. first few days the car didnt really seem to mind it, only noticed a little hesitation when letting of the gas then getting back on it. then after the first week it started going down hill and every other light or so my car would stall. after that off went the rfl and back on went the stocker.

wrxtunr it probably just needed tuning of the BOV its self, the spring sounds like it was too loose. i too had to tune mine because it was opening during part throttle, so i just got the next step heavier spring and that took care of it. Though i never did get any stalling problems, ever.