2002 WRX 12xk 3" turbo back exhaust stage 2 with cobb ap2 I wouldn't call it a problem, just well, call it what you want. here is what is going on. And all this sorta started happening after i installed 3" tbe. 1st gear, I'm not happy with full spool at all. sometimes 10psi sometimes this and that. 2nd gear same thing 3rd gear and up are fine, spool up to about 15.xpsi As you can see, im not hitting full boost. Is this cus 3" is too fat for the stock turbo and its lagging it? I wanted to take my car to SS to tune it for me. But I wana see if this 3" turboback exhaust will give him hard team to reach the best results. Or can he do his magic and have the car running good with this exhaust. If not, I dont have a problem going down to 2" or 2.5, what ever suits the car best.
If I am correct, the ECU limits the boost in 1st and 2nd gear. I believe it is limited to around 10 PSI. I know that I don't hit full boost in 1st or 2nd gears, but 3rd and up I do.
I dont believe it is limited or controllable on that year. Just last friday, I asked SS that exactly, well I stated "let the boost run loose" in all gears on the kill map. I guess to do per gear you need the avcr or whatever
I had the same setup on my bugeye.. I think your car is acting exactly like it should. Obviously a protune would be best, but not 100% necessary. Your not gonna hit full boost in 1st and 2nd... My bugeye ran great on regular stg. 2...
It's not so much the ECU not working or working as the fact that there is no gear specific wastegate duty cycle control in the Subaru ECU's. That means the same wastegate duty cycles for any give load and RPM will be used if it is in 1st gear or 5th gear. So, in order to make sure the car is not overboosting in 5th or 4th gear, you have to set the wastegate duty cycles lower. The end result is that it will usually not hit full boost in 1st and 2nd. The AVCR allows gear specific boost control. So you can set different wastegate duty cycles for each gear. 1st gear you may need 95% duty cycles to hit target where as 5th you may only need 50%. Hope that helps.
Dude, do some research... most, if not all aftermarket TBE for our cars is 3" (with the exception of a few 2.5" catback systems.) What did you use to calculate the boost with? Alot of boost gauges aren't accurate, or have a tiny hairpin hole in a line somewhere. Did you reflash it with a Cobb Accessport? If not you either need to do so, or need a protune. Untuned Im sure its normal to not reach full boost when adding a bigger exhaust system, if Im not mistaken I believe it'll make you run lean without a proper tune.
^^ I've had someone tell me on here that 3" is to wide for the stock turbo. So thats why I brought that up. I read the boost with a boost gauge and with the cobb ap2. I guess I'll just take my car for a pro tune. (I wanted to do this anyways, cant go wrong with pro tune)
It looks like most questions are answered The AVCR gets rpm and vehicle speed. You set up what ratio of rpm to vs is for each gear. Another way to look at the boost per gear is that there isn't time to fully spool the turbo in the lower gears. It takes load to make exhaust energy to spin the turbo, and there is just the shear inertia of spinning those wheels to 100,000+ rpm. A stock gauge also lags BAD, so you might be getting to 16 up top in first, but the gauge is still behind it... A Protune certainly helps (not fixes entirely, but helps) the spool in the first 2 gears. Siegel
According to their( cobb) website you should be hitting approximately 14.7 p.s.i.I am planning on buying an accessport based on this information.If this is not the norm than let me know .For my 06 I figured getting more boost is not as hard ..2.5 L.vs. 2.0 L.