clockwise33
New York Giants Fanatic
- Location
- NJ
Hello again guys,
I wanted to share some good results of a recent project on my MKV. I've got my APR K04 dialed in really nicely lately with more time for logging. It pulls hard and smooth to red line, peaks 260ish g/s MAF, about 315whp on Virtual Dyno. One slight issue has been occasional overboosting past the sensor max (about 26psi on the gauge), especially when shifting and getting back on the throttle. This never throws a code, however you can see the ECU correcting by closing the throttle and pulling timing for protection, making the car actually feel slower. I decided to try plumbing in a simple ball/spring MBC in parallel to the N75, exactly how it is described in this link: http://www.boostvalve.com/vw-1.8t-overboost-fix.html. In my opinion, this is needed for a K04 to run right on a car with the 2.55bar boost sensor because the requested boost is so close to the sensor max. This is why most K04 tunes for TSI and some for FSI require the 3bar sensor, however my car is a 2006 and the ECU is not compatible with a 3bar sensor.
It was a big pain to install with very little space to work, however it worked flawlessly. Basically, you are setting the absolute max that the boost can reach, while allowing the ECU to maintain control. The below graphs show how the MBC fixed the spiking on a WOT 3-4 shift on back to back days on the same road and conditions.
Boost spiking above sensor max causing throttle closure and timing pull:
Boost spike above sensor max eliminated by MBC, keeping ECU happy:
I wanted to share some good results of a recent project on my MKV. I've got my APR K04 dialed in really nicely lately with more time for logging. It pulls hard and smooth to red line, peaks 260ish g/s MAF, about 315whp on Virtual Dyno. One slight issue has been occasional overboosting past the sensor max (about 26psi on the gauge), especially when shifting and getting back on the throttle. This never throws a code, however you can see the ECU correcting by closing the throttle and pulling timing for protection, making the car actually feel slower. I decided to try plumbing in a simple ball/spring MBC in parallel to the N75, exactly how it is described in this link: http://www.boostvalve.com/vw-1.8t-overboost-fix.html. In my opinion, this is needed for a K04 to run right on a car with the 2.55bar boost sensor because the requested boost is so close to the sensor max. This is why most K04 tunes for TSI and some for FSI require the 3bar sensor, however my car is a 2006 and the ECU is not compatible with a 3bar sensor.
It was a big pain to install with very little space to work, however it worked flawlessly. Basically, you are setting the absolute max that the boost can reach, while allowing the ECU to maintain control. The below graphs show how the MBC fixed the spiking on a WOT 3-4 shift on back to back days on the same road and conditions.
Boost spiking above sensor max causing throttle closure and timing pull:
Boost spike above sensor max eliminated by MBC, keeping ECU happy: