OM603 semi-super pump testing, fitted with Bosch 6.0mm elements
OM603 semi-super pump testing, fitted with Bosch 6.0mm elements
115hp / 160tq at wheels, uncorrected, stock IP
141hp / 201tq at wheels, uncorrected, hybrid IP
153hp / 205tq at wheels, uncorrected, hybrid IP, 350SDL turbo
140hp / 195tq at crank, uncorrected, stock IP
172hp / 245tq at crank, uncorrected, hybrid IP
187hp / 250tq at crank, uncorrected, hybrid IP, 350SDL turbo
Some comments:
1) The power curve is much better now, the shape follows the stock curve, which is good - doesn't taper off like with the KKK.
2) Boost pressure remains above 20psi to redline, which is also good. However IAT's are off the hook! Near 5000rpm I saw 300°F IAT on the dyno. Yikes! Need an IC to cool things down.
3) There is noticeable smoke at low RPM's until boost builds, then the smoke clears. It would be nice to reduce the low-RPM smoking but I'm not sure how we can do that without hurting power elsewhere.
4) Although I did all three dyno runs to an indicated 5200rpm on the tach, only one showed pulling past 5k. I'm not sure if the tach is off, or if it was a dyno operator glitch, or what. That's annoying.
5) The one run that shows pulling to 5200rpm has the power slipping at 4750 and then past 5000 it drops like a rock. I'm thinking we may need to increase the max RPM (high idle) setting to keep the governor from spoiling the party. I want the power strong to at least 5000 before it falls off, and I think we have a few hundred RPM left to play with here.
6) The power numbers are still a bit less than expected, however the performance data is pretty good, IMO. I am still using uncorrected numbers, but I included the graphs for SAE correction for grins.
My conclusions to date: The 3.5L turbo is adequate - barely - for the 6mm pump. The compressor is just a bit small to handle the high boost levels so it's superheating the intake air. A T3/T4 hybrid (or something similar) may work better? Or just a slightly larger compressor, still in T3 trim. The EGT's remained at safe levels on the dyno (~1200F peak). I forgot to bring a video camera to capture the gauge readings on the dyno, it's not easy watching four gauges (tach, IAT, EGT, boost) simultaneously and also remembering to lift off the throttle at 5200. Next time.
Still to come: Videos during an acceleration run, but that will have to wait. It's snowing outside.
Dave M.
Boise, ID, USA
1997 E420 - 149kmi (Bugeyes)
1994 E420 - 136kmi (Blondie)
1994 E500 - 116kmi (Q-ship)
1992 500E - 179kmi (Mach 5)
1987 300D - 330kmi (Sportline Stage 2)
Click here for my website!
I went to the dyno today - see attached graphs. Rear wheel numbers are divide numbers by 0.82 to get estimated crankshaft HP:
115hp / 160tq at wheels, uncorrected, stock IP
141hp / 201tq at wheels, uncorrected, hybrid IP
153hp / 205tq at wheels, uncorrected, hybrid IP, 350SDL turbo
140hp / 195tq at crank, uncorrected, stock IP
172hp / 245tq at crank, uncorrected, hybrid IP
187hp / 250tq at crank, uncorrected, hybrid IP, 350SDL turbo
Some comments:
1) The power curve is much better now, the shape follows the stock curve, which is good - doesn't taper off like with the KKK.
2) Boost pressure remains above 20psi to redline, which is also good. However IAT's are off the hook! Near 5000rpm I saw 300°F IAT on the dyno. Yikes! Need an IC to cool things down.
3) There is noticeable smoke at low RPM's until boost builds, then the smoke clears. It would be nice to reduce the low-RPM smoking but I'm not sure how we can do that without hurting power elsewhere.
4) Although I did all three dyno runs to an indicated 5200rpm on the tach, only one showed pulling past 5k. I'm not sure if the tach is off, or if it was a dyno operator glitch, or what. That's annoying.
5) The one run that shows pulling to 5200rpm has the power slipping at 4750 and then past 5000 it drops like a rock. I'm thinking we may need to increase the max RPM (high idle) setting to keep the governor from spoiling the party. I want the power strong to at least 5000 before it falls off, and I think we have a few hundred RPM left to play with here.
6) The power numbers are still a bit less than expected, however the performance data is pretty good, IMO. I am still using uncorrected numbers, but I included the graphs for SAE correction for grins.
My conclusions to date: The 3.5L turbo is adequate - barely - for the 6mm pump. The compressor is just a bit small to handle the high boost levels so it's superheating the intake air. A T3/T4 hybrid (or something similar) may work better? Or just a slightly larger compressor, still in T3 trim. The EGT's remained at safe levels on the dyno (~1200F peak). I forgot to bring a video camera to capture the gauge readings on the dyno, it's not easy watching four gauges (tach, IAT, EGT, boost) simultaneously and also remembering to lift off the throttle at 5200. Next time.
Still to come: Videos during an acceleration run, but that will have to wait. It's snowing outside.
Dave M.
Boise, ID, USA
1997 E420 - 149kmi (Bugeyes)
1994 E420 - 136kmi (Blondie)
1994 E500 - 116kmi (Q-ship)
1992 500E - 179kmi (Mach 5)
1987 300D - 330kmi (Sportline Stage 2)
Click here for my website!
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