Agency Power Header Install and Review
Thread Starter
Member
Joined: Aug 2010
Posts: 122
Likes: 2
From: Houston, TX
2009 C63
Agency Power Header Install and Review
I haven’t seen a lot of product reviews or write ups lately, so I thought I would share my review of the Agency power headers and mid pipes.
Initial Inspection
When I received the headers and mid pipes everything was packaged well and nothing was damaged. The construction of the headers and mid pipes also looks topnotch. The TIG welding on these pieces really looks quality. The merge collectors seem to be very well designed. There is a velocity spike where the four primaries meet. The fit and finish of the product is really impressive overall.
Installation
We began the installation at around 10am, and thanks to the help of MBWorld members Shardul and MeKantor, we finished up a little after midnight. The stock manifolds are an incredible pain to get out. Everything is very straight forward, but it is very time consuming and can wear on you patience. You will need every 11mm socket, extension, and wrench combination you can think of. Some attempting to do this may find it beneficial to remove the heat shield for extra space. We did not do that, and it might have cost us some time. We did remove the coils and wire to make room on the driver's side. We also removed the steering shaft. When installing the headers, start with the primaries closest to the front of the car, and work your way to the rear of the car. I ended up reusing the gaskets and studs, and so far, I don't have any leaks. Do not tighten the studs all the way. Leave some play. This will make it easier to slip the collectors over the primaries. Once the primaries are on you can go back and tighten the studs down on the primary flanges. I also recommend swapping the O2 sensors while the collectors are uninstalled. The mid pipes are very easy to install and bolt up perfectly to the stock resonator using the stock clamps. New clamps are provided for the connection to the collectors. The collectors also bolt up to the bracket where the OEM primary cats/down pipe assemblies bolted up. These bolts are not included. They should be M8x1.25 bolts. I picked some up from at a local auto parts store. This is a very nice feature that helps keep everything tight and stable.
Installed product review
They are LOUD! Cold starts will startle some people. The car sounds seriously mean. I really don't think you can get a more aggressive tone without going to straight pipes or cutouts. The You Tube link below is of the very first startup after the install (at around midnight).
http://www.youtube.com/watch?v=quEIDy-ZJ00
Even though they are loud, they are very daily drivable. At cruising speeds there is absolutely no drone. There is also no vibration or rattling of the exhaust even at wide open throttle. Another plus about the Agency Power headers is that they will not set off your CEL. There is no need to have your tuner remove the CEL after the install.
Last weekend, I took the car to a Eurocharged dyno day to get the car retuned after the header install. It literally caught everyone off guard with how loud it was. It was an extremely hot and nasty day (far from ideal for dyno gains), but the car picked up about 25 rwhp over its previous baseline with just a tune.
I am very pleased the product, and I can recommend it to anyone looking for a more aggressive exhaust note and more horse power.
I hope this review was helpful. I will be posting up more videos soon. Let me know if you have any questions about the install or the headers.
Initial Inspection
When I received the headers and mid pipes everything was packaged well and nothing was damaged. The construction of the headers and mid pipes also looks topnotch. The TIG welding on these pieces really looks quality. The merge collectors seem to be very well designed. There is a velocity spike where the four primaries meet. The fit and finish of the product is really impressive overall.
Installation
We began the installation at around 10am, and thanks to the help of MBWorld members Shardul and MeKantor, we finished up a little after midnight. The stock manifolds are an incredible pain to get out. Everything is very straight forward, but it is very time consuming and can wear on you patience. You will need every 11mm socket, extension, and wrench combination you can think of. Some attempting to do this may find it beneficial to remove the heat shield for extra space. We did not do that, and it might have cost us some time. We did remove the coils and wire to make room on the driver's side. We also removed the steering shaft. When installing the headers, start with the primaries closest to the front of the car, and work your way to the rear of the car. I ended up reusing the gaskets and studs, and so far, I don't have any leaks. Do not tighten the studs all the way. Leave some play. This will make it easier to slip the collectors over the primaries. Once the primaries are on you can go back and tighten the studs down on the primary flanges. I also recommend swapping the O2 sensors while the collectors are uninstalled. The mid pipes are very easy to install and bolt up perfectly to the stock resonator using the stock clamps. New clamps are provided for the connection to the collectors. The collectors also bolt up to the bracket where the OEM primary cats/down pipe assemblies bolted up. These bolts are not included. They should be M8x1.25 bolts. I picked some up from at a local auto parts store. This is a very nice feature that helps keep everything tight and stable.
Installed product review
They are LOUD! Cold starts will startle some people. The car sounds seriously mean. I really don't think you can get a more aggressive tone without going to straight pipes or cutouts. The You Tube link below is of the very first startup after the install (at around midnight).
http://www.youtube.com/watch?v=quEIDy-ZJ00
Even though they are loud, they are very daily drivable. At cruising speeds there is absolutely no drone. There is also no vibration or rattling of the exhaust even at wide open throttle. Another plus about the Agency Power headers is that they will not set off your CEL. There is no need to have your tuner remove the CEL after the install.
Last weekend, I took the car to a Eurocharged dyno day to get the car retuned after the header install. It literally caught everyone off guard with how loud it was. It was an extremely hot and nasty day (far from ideal for dyno gains), but the car picked up about 25 rwhp over its previous baseline with just a tune.
I am very pleased the product, and I can recommend it to anyone looking for a more aggressive exhaust note and more horse power.
I hope this review was helpful. I will be posting up more videos soon. Let me know if you have any questions about the install or the headers.
Last edited by TexasEngineer; Aug 3, 2011 at 01:31 PM.
MBWorld Fanatic!
Joined: Jul 2009
Posts: 6,677
Likes: 4
From: Los Angeles
C63
Great review!!
The quality looks great. Does Agency power make a X pipe as an option if you wanna replace the straight mid pipes?
Lets see some videos.
The quality looks great. Does Agency power make a X pipe as an option if you wanna replace the straight mid pipes?
Lets see some videos.
Last edited by _AMG_; Aug 3, 2011 at 02:37 PM.
Thread Starter
Member
Joined: Aug 2010
Posts: 122
Likes: 2
From: Houston, TX
2009 C63
http://www.agency-power.com/catalog/...h52m171et0grl5
I will try to get some videos done over the weekend.
Trending Topics
MB World Stories
The Best of Mercedes & AMG
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
SPONSOR
Joined: Feb 2011
Posts: 537
Likes: 0
From: Gilbert AZ
C63
Here is a quick video of my car on the dyno a few minutes ago.
http://www.youtube.com/watch?v=G0sHhxZ0tvk
http://www.youtube.com/watch?v=G0sHhxZ0tvk
Junior Member
Joined: Jul 2007
Posts: 56
Likes: 0
From: Centreville, VA
2011 C63 AMG
How many labor hours would it have been to install the headers if you didn't do it yourself?
That sounded amazing btw...I'm picking mine up tomorrow and I would love to have mine sound like that.
That sounded amazing btw...I'm picking mine up tomorrow and I would love to have mine sound like that.
MBWorld Fanatic!
Joined: Aug 2009
Posts: 1,699
Likes: 4
From: Tucson, AZ
C63 AMG
The sound is great and the looks and finish is astonishing, it looks like a quality piece. Explain me something though, did you picked only 25whp after adding these headers and got it retuned? typically the long tube headers yield more power no? I am not trying to argue here I am just saying that typically you see higher gains with the addition of the LTH specially since Eurocharge now has an improved software(V3).. my 2c.
Last edited by C63newdude; Aug 5, 2011 at 09:15 PM.
MBWorld Fanatic!
Joined: Aug 2010
Posts: 2,493
Likes: 3
MB
The sound is great and the looks and finish is astonishing, it looks like a quality piece. Explain me something though, did you picked only 25whp after adding these headers and get it retune? typically the long tube headers yield more power no? I am not trying to argue here I am just saying that typically you see higher gains with the addition of the LTH specially since Eurocharge now has an improved software(V3).. my 2c.
So, the V3 tune was in the high 380's and, now with the headers it's at like 413 rwhp. And like he said, it wasn't the greatest weather for big dyno numbers.
Still, 25 whp gain is solid and it would definitely be more out on the open road, especially when the weather is better.
Thread Starter
Member
Joined: Aug 2010
Posts: 122
Likes: 2
From: Houston, TX
2009 C63
Thread Starter
Member
Joined: Aug 2010
Posts: 122
Likes: 2
From: Houston, TX
2009 C63
The sound is great and the looks and finish is astonishing, it looks like a quality piece. Explain me something though, did you picked only 25whp after adding these headers and get it retune? typically the long tube headers yield more power no? I am not trying to argue here I am just saying that typically you see higher gains with the addition of the LTH specially since Eurocharge now has an improved software(V3).. my 2c.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 2,087
Likes: 6
360 Modena TT
wait for cooler temps if your looking for better dyno #s . the track will be the true test but i noticed the temp had a lot to do with the #s i got on my dyno run with long tubes and tune . i dynoed mine during a 97 degree day and it was windy as hell . i only put down 460 whp . i'm sure my #s will increase during a cooler day , which here in El Paso is about once a year . 
congrats on your new setup
congrats on your new setup
Thread Starter
Member
Joined: Aug 2010
Posts: 122
Likes: 2
From: Houston, TX
2009 C63
So I am finally getting around to posting up some videos. The first video is an in car shot. I wanted to show what it sounded like at wide open throttle, cruising speed, and at part throttle. I would describe the new exhaust as sounding like the OEM exhaust only much louder and slightly raspier. It is very aggressive sounding grabs a lot of attention even at part throttle.
http://www.youtube.com/watch?v=6jf8W5P21p4
http://www.youtube.com/watch?v=PUVbEjjfcIU
http://www.youtube.com/watch?v=OSSQ-7fYmp4
http://www.youtube.com/watch?v=lDvl8RRzAGs
http://www.youtube.com/watch?v=Dh7b2uBoQ8k
http://www.youtube.com/watch?v=6jf8W5P21p4
http://www.youtube.com/watch?v=PUVbEjjfcIU
http://www.youtube.com/watch?v=OSSQ-7fYmp4
http://www.youtube.com/watch?v=lDvl8RRzAGs
http://www.youtube.com/watch?v=Dh7b2uBoQ8k
Junior Member
Joined: Sep 2013
Posts: 50
Likes: 1
From: Sydney, Australia
GTS
Couple of questions on this, assuming you're still around on this forum
1 - Did the 14hour install cover just the headers? Or is that the full system + wiring the valvetronic gear?
2 - So aside from taking bits off to clear up some space, is there any other 'gotchas' that would save a young punter like me doing it at home?
Cheers,
Dan
1 - Did the 14hour install cover just the headers? Or is that the full system + wiring the valvetronic gear?
2 - So aside from taking bits off to clear up some space, is there any other 'gotchas' that would save a young punter like me doing it at home?
Cheers,
Dan
