giannisanag
New Member
- Joined
- Apr 3, 2009
- Messages
- 5
Hi again,
I need help regarding a supercharger issue.
My car is a manual w203 c200 Kompressor MY2002, with the M111 engine producing originally 163ps.
In its standard form the car was working under a boost level of 0,37 bar at full throttle. Near the rev limiter this could go a bit higjer (mainly i think due to flow issues).
One year ago i replaced the crank pulley with a bigger one (230mm) sending the boost to 0.68 (0.73 max at rev limiter ). There was a huge increease in performance (dyno showed 214bhp and 290NM of torque and the car was able of constant 7.0s-7.3s for the 0-60mph and once an impressive 14.8s for 1/4mile) a small decrease in fuel economy and everything worked perfect. 4 months later i put custom headers and last march i put a bigger intercooler as summers in greece are hot.
I noticed something was wrong just before putting on the new intercooler. The scanguage readings showed a drop in pressure. the 0.60 had become 0.55 and from 4000-5000rpm dropped to 0.50, and then it would go up again. Just before the rev limiter the 0.73 became 0.68.
I dynoed the car before the Intercooler install. Hence i was right. 202bhp and 270nm of torque.
We installed the intercooler and thorougly checked for leaks. no sign of them.
We dynoed with the intercooler: 212bhp and 28nm of torque.
With the new intercooler pressure dropped a bit more:the 0.55 became 0.50.
And the hole remains. between 4000-5000 the pressure drops to 0.48 and then it goes up. The gain of the ic was that due to better Intake temperatures the ECU gives timing advance of 17-19 degrees at full throttle while before the IC the figures where 12-13 degrees.
Given that for almost 30.000km the pressure was stable (so this must not be an ecu problem) what could be the problem? I suspect the supercharger bypass valve, but i am not sure. the car cannot drop below 7.9 for the 0-60mph and the 15.8 for the 1/4 mile.
To help those who might want to help me i give the following information:
1. all dyno's at the same dyno, first one april 2009, other two on march 2010, tank filled with the same type of gasoline from the same gas station.
2. i frequently erase the ecu adaptation data. Especially before dynos or after mods to allow the ecu to adapt more easily
3. funny thing: outside temps dropped and the 0.50 became 0.56 again (and drops to 0.49 between 4000-5000.
4. i suspect that the ecu open the bypass valve for some reason (maybe outside temps, or over a certain intake temperature)
5. I also supsect that the bypass valve does not totally close maybe due to normal wear but how can i be sure. Star diagnosis showed no problem at all.
6. use the racelogic driftbox to run my performance tests, the scangauge to monitor obd readings, the carsoft for diagnostic purposes and several obd programs installed in my laptop and cell phone for data logging
7. what is the max pressure that the ecu allows?
Any clues would be much appreciated.
I need help regarding a supercharger issue.
My car is a manual w203 c200 Kompressor MY2002, with the M111 engine producing originally 163ps.
In its standard form the car was working under a boost level of 0,37 bar at full throttle. Near the rev limiter this could go a bit higjer (mainly i think due to flow issues).
One year ago i replaced the crank pulley with a bigger one (230mm) sending the boost to 0.68 (0.73 max at rev limiter ). There was a huge increease in performance (dyno showed 214bhp and 290NM of torque and the car was able of constant 7.0s-7.3s for the 0-60mph and once an impressive 14.8s for 1/4mile) a small decrease in fuel economy and everything worked perfect. 4 months later i put custom headers and last march i put a bigger intercooler as summers in greece are hot.
I noticed something was wrong just before putting on the new intercooler. The scanguage readings showed a drop in pressure. the 0.60 had become 0.55 and from 4000-5000rpm dropped to 0.50, and then it would go up again. Just before the rev limiter the 0.73 became 0.68.
I dynoed the car before the Intercooler install. Hence i was right. 202bhp and 270nm of torque.
We installed the intercooler and thorougly checked for leaks. no sign of them.
We dynoed with the intercooler: 212bhp and 28nm of torque.
With the new intercooler pressure dropped a bit more:the 0.55 became 0.50.
And the hole remains. between 4000-5000 the pressure drops to 0.48 and then it goes up. The gain of the ic was that due to better Intake temperatures the ECU gives timing advance of 17-19 degrees at full throttle while before the IC the figures where 12-13 degrees.
Given that for almost 30.000km the pressure was stable (so this must not be an ecu problem) what could be the problem? I suspect the supercharger bypass valve, but i am not sure. the car cannot drop below 7.9 for the 0-60mph and the 15.8 for the 1/4 mile.
To help those who might want to help me i give the following information:
1. all dyno's at the same dyno, first one april 2009, other two on march 2010, tank filled with the same type of gasoline from the same gas station.
2. i frequently erase the ecu adaptation data. Especially before dynos or after mods to allow the ecu to adapt more easily
3. funny thing: outside temps dropped and the 0.50 became 0.56 again (and drops to 0.49 between 4000-5000.
4. i suspect that the ecu open the bypass valve for some reason (maybe outside temps, or over a certain intake temperature)
5. I also supsect that the bypass valve does not totally close maybe due to normal wear but how can i be sure. Star diagnosis showed no problem at all.
6. use the racelogic driftbox to run my performance tests, the scangauge to monitor obd readings, the carsoft for diagnostic purposes and several obd programs installed in my laptop and cell phone for data logging
7. what is the max pressure that the ecu allows?
Any clues would be much appreciated.
