2005 c55 Dyno after exhaust work
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2005 c55 Dyno after exhaust work
Last week I put my 2005 C55 with 65k miles on the dyno, pulled 294hp and 318tq to the wheels. Afterwards I had the secondary cats removed and the resonator replaced with a straight pipe. I love the sound, and like the power gains. Tonight the car put down 310hp and 340tq. I loooovvveeeee this car.
I will have a pic up in the next few days, once the shop emails it to me.
I will have a pic up in the next few days, once the shop emails it to me.
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2013 C63 AMG P31, 2014 GMC Sierra (6.2)
Is this on the same dyno, same conditions (IE rim/tire size etc)? If so, that's fantastic! You, hooleyboy, AMS and a few others have shown a very good gain from removing the secondary cats. It's basically free power! Were your gains throughout the entire rpm range or did you find you gained more in the higher rpms as opposed to the lower? Oh, and is this with a stock ecu?
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Gains were all the way through the powerband. The car is completely stock except for the exhaust mod and the door lock knobs.
The pulls were done on 2 different days, but the only difference was the out side temp, the first pull it was 86 deg, today it was 80 deg, humidity, barometric pressure was damn near exact, the dyno had a correction factor of .01.
The pulls were done on 2 different days, but the only difference was the out side temp, the first pull it was 86 deg, today it was 80 deg, humidity, barometric pressure was damn near exact, the dyno had a correction factor of .01.
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AMG
Summary of some of the NA 55 AMG 2nd cat dynos:
AMS 300cell 2nd cats = 10HP / 12 TQ Dyno Dynamics
Hooley 2nd delete = 13HP / 19 TQ Dyno Dynamics
Bryan's 2nd delete = 16HP / 22 TQ (dyno unknown, maybe dynojet?)
What is most impressive is that just by going from a 400 OEM to 300cell metal core cat you get roughly 60-75% of the gains with almost no change in emissions (for those that are very environmentally conscious). With that said, 2nd cats do give you more sound than stock but still refine the exhaust note more so than straight pipes, so the high flow cats are a good alternative to going complete straight pipes for those worrying about not passing the visual inspection.
More dyno info (brand & model dyno, pre/post temps/humidity, etc) would be appreciated just to gather more data for the AMG community as a whole.
AMS 300cell 2nd cats = 10HP / 12 TQ Dyno Dynamics
Hooley 2nd delete = 13HP / 19 TQ Dyno Dynamics
Bryan's 2nd delete = 16HP / 22 TQ (dyno unknown, maybe dynojet?)
What is most impressive is that just by going from a 400 OEM to 300cell metal core cat you get roughly 60-75% of the gains with almost no change in emissions (for those that are very environmentally conscious). With that said, 2nd cats do give you more sound than stock but still refine the exhaust note more so than straight pipes, so the high flow cats are a good alternative to going complete straight pipes for those worrying about not passing the visual inspection.
More dyno info (brand & model dyno, pre/post temps/humidity, etc) would be appreciated just to gather more data for the AMG community as a whole.
Last edited by AMS Performance; Sep 2, 2009 at 02:36 AM.
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AMG
For some reason the few tests that have been performed showed no gains on C32. Again, its difficult to determine the accuracy of the tests so it may be just that the tests were inconclusive due to inaccurate testing methods. The 5.5L NA engines love high flow cats though (especially in conjunction with headers such as our short tube bolt on headers, and long tubes as well). Hope that helps.
~AMS~
~AMS~
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02 C32 AMG
from what i have read in many threads, for some reason the C32 guys do not gain any real power from exhaust work other than headers. that is where you will see the most gain.
the resonator delete will drop you a couple pounds and alter the sound; no change in power. high flow/race primary cats will add you maybe a couple hp, and deleted secondaries have not shown any power, maybe 1whp? mostly deleting the secondaries on the C32 have just made the car louder, not changing the sound, but making it louder.
however, i have heard that if you run headers, you may see some smallish gains from deleting the secondaries, resonator, and running high flow primaries as the stock exhaust manifolds were the main bottleneck in the exhaust, and taking care of all those other parts just fine tunes it for perhaps a little better exhaust flow.
the resonator delete will drop you a couple pounds and alter the sound; no change in power. high flow/race primary cats will add you maybe a couple hp, and deleted secondaries have not shown any power, maybe 1whp? mostly deleting the secondaries on the C32 have just made the car louder, not changing the sound, but making it louder.
however, i have heard that if you run headers, you may see some smallish gains from deleting the secondaries, resonator, and running high flow primaries as the stock exhaust manifolds were the main bottleneck in the exhaust, and taking care of all those other parts just fine tunes it for perhaps a little better exhaust flow.
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AMG
Correct JT,
It appears there is a linear relationship with gains from catalytic converters and engine displacement on these AMG engines (FI or NA seems irrelevant). The smaller displacement V6s simply don't show much gains (if any at all). This seems counter intuitive since both should be moving roughly the same air in case of C32 vs. C55, but that's just how it works sometimes.
It appears there is a linear relationship with gains from catalytic converters and engine displacement on these AMG engines (FI or NA seems irrelevant). The smaller displacement V6s simply don't show much gains (if any at all). This seems counter intuitive since both should be moving roughly the same air in case of C32 vs. C55, but that's just how it works sometimes.
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From: Keesler AFB, Gulfport, MS
C32 AMG
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I have to say the only down side to making the power I did was to see the 2007 Z06 on the lift in front of me getting a built blown motor and auto trans installed, the Gone in 60 Seconds authorized Elanor replica with a built a procharged motor next to my car, the 700hp whipple charged ls1 saind rail buggy out side and a couple 1000rwhp 2003 cobras in the shop.
Check out the shop I had the dyno done at www.houseofboost.com
Check out the shop I had the dyno done at www.houseofboost.com
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From: Delran, NJ
05 C55
get some pics and a youtube of your exhaust please. ive been wanting to do that for some time. you should coax your friends at the shop into putting together a 5-6 psi centrifugal kit for the C55.....please 
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From: ATL
05 C55 AMG
This is great to hear about your gains. I had only deleted the resonator initially and decided a week or so ago to pull out the secondary cats too and wow what a difference in sound and the good ol butt dyno felt to pick up some power.
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02 C32 AMG
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WOW! Just a few days short of eternity later I have pics and info up! It says I only removed the resonator, but 2nd cats were removed also.
http://www.houseofboost.com/blog/
Scroll halfway down for pics.
http://www.houseofboost.com/blog/
Scroll halfway down for pics.
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From: Seattle, WA
C55
Last week I put my 2005 C55 with 65k miles on the dyno, pulled 294hp and 318tq to the wheels. Afterwards I had the secondary cats removed and the resonator replaced with a straight pipe. I love the sound, and like the power gains. Tonight the car put down 310hp and 340tq. I loooovvveeeee this car.
I will have a pic up in the next few days, once the shop emails it to me.
I will have a pic up in the next few days, once the shop emails it to me.
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Other than the exhaust work the car is stock as can be.
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AMG
In conjunction with the shorty headers, the high flow 2nd cats are a great addition. Those are the only two exhaust mods you ever really need to do on the AMGs, everything else flows really well.
