02 WRx w/82k, stage2. Say I'm going on the highway at 60mph on 5th gear and I want to past a car, kinda floor it on 5th gear (enought so that you could hear the spooling). During when I'm gasing I can feel my boost(psi) feels like its going up down, up down like when you're pressing the gas pedal and release a bit then press the gas pedal again(but speed do increase like normal). This is in 5th gear, havn't tried 4th but 3rd is fine since its close to redline. I dont have any gauges yet to tell the psi. Whats going on?
My car does the same on an off-the-shelf Stage 2 tune. You just need a better tune (read, you need a TUNE in general). And a boost gauge.
sounds like wastegate to me as well... your gonna notice it more in 5th gear as it provides a higher load on the engine which = more boost. Sence you said your stage 2 im thinking it could be creeping, so my guess would be your wastegate duty cycle is struggling to maintain. Get your self a boost gauge, In my book guages should be the very very first mod (if you can really call it a mod).
I tuned it :eek4: LOL, just a basic stage 2. Everything was fine when we were tuning and logging (with wb02) Though we did not log 5th gear -_-
very true totaly forgot about the air tempatures changing this time of year now also helping with overboost. A simple fix might just be to throw in a boost controller inplace of retuning for every season
It's the turbo dynamics kicking in. Flooring the car in 5th will produce enough load to easily overshoot boost targets (assuming wgdcs were set during 3rd or 4th gear pulls) and the ecu will react by pulling out wg cycles. However in this case, the car is pulling out too much wastegate and thus pulls out too much boost. Then the cycle repeats itself over and over....
wait one second here buddy......we're not supposed to do that? :eek4: I do that backing out of the garage
I dont mean "floor" it like pedal to the metal, No I"m not that dumb. Enought to pass somebody on the highway.
Sounds like both the turbo dynamics are too aggressive and the wgdc at lower throttle openings are too high for the corresponding boost targets.
See below. Yes. If a tuner gets the turbo dynamics and WGDC tables correct, you can avoid this phenomenon. Without looking at the map, it's hard to say if this is caused by boost and wgdc targets that are to high in the low rpm high load areas, or caused by mistuned IAT WGDC corrections. Both could cause some boost bounce in the higher gears.
stock bcs Yes, the stock values can be tuned to help it, but I left it alone, didn't know mister blackout was gonna be flooring it in 5th gear in cold weather :ugh:
sounds like you're over shooting the boost target. Not a big deal. Should take a little time to correct.
