Only 140-150rwhp!?
Thread Starter
Senior Member
Joined: Jun 2005
Posts: 264
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From: Houston, TX
2010 C300
Only 140-150rwhp!?
Ok - so I've got a problem here...
I had before / after dyno's run on my car (had the ASP prototype pulley installed - but that's another story - on another forum). Anyway, both times, my car was only making about 140-150rwhp. The car has been in for service a month or so ago, where they replaced 2 coilpacks and all the plugs. The car idles alright, a little rough, but nothing that seems unusual.
The shop is a reputable one... (one of the biggest porsche shops around), but they don't do much work on MB's. They weren't able to pick up a voltage to get the RPM's - so all they could get was hp vs. mph. Right up near the top, the computer just starts dumping fuel in and the a/f ratio goes to hell. Again, we didn't have the tach, but in driving, this seems to happen about 4-4.5k RPM. Car was in dyno mode for all runs.
Anyway - my question is - what could contribute to such a drastic loss in power? (I got these numbers both BEFORE and after the new pulleys were installed). I have one of the runs with a/f ratios in excel, that I can post if that would help...
Some things that have been suggested to me already:
Check the gap in the plugs (don't think this would cause such a huge drop in power though)
Bypass valve stuck open?
Any info is appreciated.
I had before / after dyno's run on my car (had the ASP prototype pulley installed - but that's another story - on another forum). Anyway, both times, my car was only making about 140-150rwhp. The car has been in for service a month or so ago, where they replaced 2 coilpacks and all the plugs. The car idles alright, a little rough, but nothing that seems unusual.
The shop is a reputable one... (one of the biggest porsche shops around), but they don't do much work on MB's. They weren't able to pick up a voltage to get the RPM's - so all they could get was hp vs. mph. Right up near the top, the computer just starts dumping fuel in and the a/f ratio goes to hell. Again, we didn't have the tach, but in driving, this seems to happen about 4-4.5k RPM. Car was in dyno mode for all runs.
Anyway - my question is - what could contribute to such a drastic loss in power? (I got these numbers both BEFORE and after the new pulleys were installed). I have one of the runs with a/f ratios in excel, that I can post if that would help...
Some things that have been suggested to me already:
Check the gap in the plugs (don't think this would cause such a huge drop in power though)
Bypass valve stuck open?
Any info is appreciated.
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Blimp
Originally Posted by HoustonC230
Ok - so I've got a problem here...
I had before / after dyno's run on my car (had the ASP prototype pulley installed - but that's another story - on another forum). Anyway, both times, my car was only making about 140-150rwhp. The car has been in for service a month or so ago, where they replaced 2 coilpacks and all the plugs. The car idles alright, a little rough, but nothing that seems unusual.
The shop is a reputable one... (one of the biggest porsche shops around), but they don't do much work on MB's. They weren't able to pick up a voltage to get the RPM's - so all they could get was hp vs. mph. Right up near the top, the computer just starts dumping fuel in and the a/f ratio goes to hell. Again, we didn't have the tach, but in driving, this seems to happen about 4-4.5k RPM. Car was in dyno mode for all runs.
Anyway - my question is - what could contribute to such a drastic loss in power? (I got these numbers both BEFORE and after the new pulleys were installed). I have one of the runs with a/f ratios in excel, that I can post if that would help...
Some things that have been suggested to me already:
Check the gap in the plugs (don't think this would cause such a huge drop in power though)
Bypass valve stuck open?
Any info is appreciated.
I had before / after dyno's run on my car (had the ASP prototype pulley installed - but that's another story - on another forum). Anyway, both times, my car was only making about 140-150rwhp. The car has been in for service a month or so ago, where they replaced 2 coilpacks and all the plugs. The car idles alright, a little rough, but nothing that seems unusual.
The shop is a reputable one... (one of the biggest porsche shops around), but they don't do much work on MB's. They weren't able to pick up a voltage to get the RPM's - so all they could get was hp vs. mph. Right up near the top, the computer just starts dumping fuel in and the a/f ratio goes to hell. Again, we didn't have the tach, but in driving, this seems to happen about 4-4.5k RPM. Car was in dyno mode for all runs.
Anyway - my question is - what could contribute to such a drastic loss in power? (I got these numbers both BEFORE and after the new pulleys were installed). I have one of the runs with a/f ratios in excel, that I can post if that would help...
Some things that have been suggested to me already:
Check the gap in the plugs (don't think this would cause such a huge drop in power though)
Bypass valve stuck open?
Any info is appreciated.
Thread Starter
Senior Member
Joined: Jun 2005
Posts: 264
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From: Houston, TX
2010 C300
Originally Posted by Sauceboy01
Well, your car stock produces right around 160 RWHP.. so you're not down all that much!
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
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From: Earth
CLS
Originally Posted by HoustonC230
All the dyno's I've seen for the M271 were up around 170. For me to get 150rwhp, that would be 21% drivetrain loss - which seems pretty damn high to me for a manual. (140rwhp = 26%)
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
Doesn't the M271 (1.8L) list at 189 hp. at the crank ? A true 170 at the wheels would be nice but that seems like an extremely low amount due to drive train loss compared to almost any other vehicle I know. Also taking into account the type of dyno used and mileage on your car.....true h.p. numbers in the 150ish range does not seem that unreasonable..
Last edited by respdoc; Dec 20, 2005 at 02:06 PM.
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is SOLD
being a manual you should lose at least 15-percent to the wheels, and if hp is at 189 and 15-percent should be in the 150-160 area stock. so 140 is pretty low even with mods.
did you only get the pulley installed. if you changed the pulley you have to mess the ecu..... now to match the a/f ratio since more air is going in the car. there could be a lot of factors......injectors, fuel pump, chipped, etc....
remember the kleemann pulley kits comes with a k-box, which is a piggy back for the ecu.
did you only get the pulley installed. if you changed the pulley you have to mess the ecu..... now to match the a/f ratio since more air is going in the car. there could be a lot of factors......injectors, fuel pump, chipped, etc....
remember the kleemann pulley kits comes with a k-box, which is a piggy back for the ecu.
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Blimp
Originally Posted by HoustonC230
All the dyno's I've seen for the M271 were up around 170. For me to get 150rwhp, that would be 21% drivetrain loss - which seems pretty damn high to me for a manual. (140rwhp = 26%)
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
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From: The blue white rock, third out.
2002 C230 Coupe(M111)
Originally Posted by HoustonC230
All the dyno's I've seen for the M271 were up around 170. For me to get 150rwhp, that would be 21% drivetrain loss - which seems pretty damn high to me for a manual. (140rwhp = 26%)
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
If I came up with a 160 - I could accept that... being a 16% loss...
I think I'm going to check my plugs, recheck all the piping - make sure nothing's loose after pulling apart the front end.
161 is a 15% loss, perfectly normal for a manual transmission car. Autos are higher loss. Clearly your car has some problems, without the pulley.
Also, the Kleeman K Box that shipped with there M271 did something to the fuel...brand never did say what. Perhaps that's why your asp pulley isn't showing any gains. First things first, your car is down some serious HP.
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From: Orange County
2005 C Wagon (No snickering please!)
Prior to the dyno run did you replace the air filter(s)? Install clean synthetic oil? Change Kompressor Oel? Fill with fresh premium fuel? Inflate the tires to the top of the range? Disable the alternator field? Unplug the AC clutch? Blow air over the radiator to keep the fan clutch spinning free? Didn't the computer have an inductive pick-up to clamp on a plug wire to compute the rpm? These items alone contribute little to the measured Hp, but together can make the difference you report.
The rough idle might be your largest clue. If two coil packs were reporting bad to the computer, I'd check the quality of the ground connection between the engine and the frame. Look carefully at the insulation of the engine wiring, especially where it connects to the coils.
I hope you can get the numbers you are paying for.
The rough idle might be your largest clue. If two coil packs were reporting bad to the computer, I'd check the quality of the ground connection between the engine and the frame. Look carefully at the insulation of the engine wiring, especially where it connects to the coils.
I hope you can get the numbers you are paying for.
Thread Starter
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Joined: Jun 2005
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From: Houston, TX
2010 C300
Originally Posted by Moviela
I hope you can get the numbers you are paying for.
There's at least one dyno floating around (I rememeber more, but could only find one during my 10 second search) where they got around 170hp. Reading a little more on the one that I found, it was a new car though, with only 20 miles... Mine has 40k.
As far as not getting any real measurable gains from the pulley - not too concerned about that. I realize that the other kits have a chip/"box" that come with them for a reason - and looking at my "after" dyno's, I'm pretty sure why. That's no big deal, I'll work on that later.
Reading everyone's posts, going back through the #'s, and settling down after getting pissed about not hitting my (unrealistic) expectations - I realize I'm not too far off where I should be. Granted I think I'm still losing a few hp here or there - it's not the 20-30 I was thinking before.
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From: The blue white rock, third out.
2002 C230 Coupe(M111)
Originally Posted by HoustonC230
There's at least one dyno floating around (I rememeber more, but could only find one during my 10 second search) where they got around 170hp.
Reading a little more on the one that I found, it was a new car though, with only 20 miles... Mine has 40k.
Properly running, there's a lot less headroom in the 1.8 compared to the 2.3...no one should be expecting a 35HP bump from this pulley. Honestly, I think 10 is about all you'll see, once the fuel and spark issues are resolved.
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From: Houston, TX
2010 C300
Originally Posted by Outland
Properly running, there's a lot less headroom in the 1.8 compared to the 2.3...no one should be expecting a 35HP bump from this pulley. Honestly, I think 10 is about all you'll see, once the fuel and spark issues are resolved.
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From: The blue white rock, third out.
2002 C230 Coupe(M111)
Originally Posted by HoustonC230
I'll be happy if I get 15-20hp from the pulley (+chip tune). If it works out, MSRP on the combo would be half of the kleemann kit... but that's a BIG if. We'll see.... regardless it's fun seeing what happens (and frustrating at times)
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Originally Posted by Outland
Where the hell did you seem an M271 with 170 at the wheels?
161 is a 15% loss, perfectly normal for a manual transmission car. Autos are higher loss. Clearly your car has some problems, without the pulley.
Also, the Kleeman K Box that shipped with there M271 did something to the fuel...brand never did say what. Perhaps that's why your asp pulley isn't showing any gains. First things first, your car is down some serious HP.
161 is a 15% loss, perfectly normal for a manual transmission car. Autos are higher loss. Clearly your car has some problems, without the pulley.
Also, the Kleeman K Box that shipped with there M271 did something to the fuel...brand never did say what. Perhaps that's why your asp pulley isn't showing any gains. First things first, your car is down some serious HP.
Originally Posted by HoustonC230
There's at least one dyno floating around (I rememeber more, but could only find one during my 10 second search) where they got around 170hp. Reading a little more on the one that I found, it was a new car though, with only 20 miles... Mine has 40k.
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From: Ohio
'02 C230K
To determine if it's the plugs or the coil pack: swap the coil packs with good cylinders and see if if the misfire code follows the pack. M111s hate cheap plugs, even slightly lesser NGKs (not sure about the M271s). Pay the man $55 and get the NGKs with the MB Star logo. Buy yourself an OBDII reader for the pricy dyno time, they're down to around $100. Better yet, do as I did and buy your brother one for a present and borrow it when needed. Good luck.
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You'll want to take into account that unless you are comparing your car to another car run on the same dyno you very well may be getting a false comparision, esp. if you're comparing an inertia dyno result to an eddy current result.
Factory Pro eddy current dynos read 14 to 15 percent lower than say, a Dynojet inertia dynamometer in the 90 to 100 horsepower range, with even more difference at higher power levels. I see this alot on racebikes, my GSXR-750 shows lower HP than my teammates even though I pull him on the straights every time, he runs on an interia dyno and I tune on an eddy dyno.
- Eric
Factory Pro eddy current dynos read 14 to 15 percent lower than say, a Dynojet inertia dynamometer in the 90 to 100 horsepower range, with even more difference at higher power levels. I see this alot on racebikes, my GSXR-750 shows lower HP than my teammates even though I pull him on the straights every time, he runs on an interia dyno and I tune on an eddy dyno.
- Eric
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From: Ohio
'02 C230K
If you pay a dealer to diagnose the car, ask the tech to see how fast the rear O2 sensor is ticking off. It's just a glorified thermometer, but it will deteriorate significantly prior to setting a code. Common scanners just read the code, MB laptops reads the data stream.
I have a new puppy named Loki (really).
I have a new puppy named Loki (really).
