AMR Performance Review

When Mercedes announced the C450 to the general public, people didn't know what to think. Sure, some of us had heard rumors that Mercedes was going to introduce a more aggressive C class but could the car actually perform. It turns out that answer was a fanominal yes. Stock the car runs amazing, but it didn't take long for tunning shops to get down and dirty with the ECU and take this impressive V6 to an entirely new level. Over the last year we reviewed many tunes for the C450. Some of those piggy backs and some flashes, but amazingly they keep getting better and now we think we have found one that may hold the crown for the foreseeable future.

Enter AMR Performance a company out of Danbury, Connecticut with a racing mindset drilled into the very core of their business. What gives AMR an edge over the competition is actually really simple. They have more time with the car. That's because they actually own one and this means that instead of just remapping the ECU, they are able to tweak variables and test them over and over again until they get the best results.

Over the last couple of months we had many people ask us if we were going to review the tune that AMR put out. The answer was always yes and now that we have had the tune to test with we are finally able to give a lot of you exactly what you have been waiting for. 


AMR offers two options for getting your ECU flashed. The first and more common is the Ship in method. With this option you are shipping the ECU to them, they will flash the ECU, and then Overnight the ECU back to you. If you are close to Danbury and want to take your car in you have the Flash and Dyno tune option. Here you will not only have the ECU flashed, but you will also get your car dyno'd and leave with the dyno sheet. 

For those of you that are worried about removing the ECU it couldn't be easier on the C450. The ECU is located on the top of the engine right under the plastic decorative plate. Simply pull up on the decorative plate which is held together by suction snaps and you have access to the ECU. There are two harnesses that connect to the ECU. The one on the right has a lever mechanism that needs to be pulled to the left and the one on the left is more of a pin type design simply grab it and pull directly to the left to release the harnesses and then pull straight up the ecu is held in place by four of the same type of suction cups as the decorative plate the whole process should take about 2 minutes. It is worth noting that before you remove the ECU you should pop the hood and wait 5 minutes. This will keep the engine from throwing a check engine light when you reinstall. If you do get a check engine light don't panic you can clear the code with an odb2 reader and if you don't have one your nearest autozone does and will gladly clear the code for you.

Initial Impressions

When we reviewed the tune from OE Tuning one thing we noted was that the burble that we have come to know and love from the c450 was not as prevalent. After some time with the tune we actually forgot about the burble and just enjoyed the enormous amount of extra horsepower that came with the car. Well The Burble Is Back! and man is it a great sound. Until now we were not able to really hear the burble through the Miesterchaft exhaust system the first time I heard it my heart started racing and my eyes lit up. Overall the shifts are smoother the car feels more responsive and the powerband feels more consistent.

It's also important to note the number of safety measures that these guys take when coding these ECUs. For instance, under a certain engine temperature the turbos are dialed back just a hair. This is because the

The Numbers

I need to preference this by stating that the Stock dyno run as well as the OE dyno run were both done with the temperature in the upper 60s the temperature on the dyno run for the AMR tune was a very hot 93.7 degrees. The other thing to note is that the stock and OE tune did not have the Miesterchaft exhaust on.

That being said the car put out 386 foot pounds of torque at the wheel and 316.5 peak horsepower. This was done again in 4th gear. 

Edit: To be completely clear this is AMRs standard stage 1 flash. They did not know about any other modifications to the car and did not account for them when tuning the ECU. 

For anyone interested in the AFR the graph is below

This is the one most people probably want to see. In red we have AMR, green is OE, and pink is Stock. As you can see even with a 30 degree increase in temperature AMR still was able to out perform OE. This is not to surprising since AMR posted their dyno numbers on their site a month or so ago, but, it's always nice to see the numbers first hand. 

Overall Impressions

When people started asking about the AMR tune I was hesitant. I really really liked the numbers that the OE tune put out and it was hard for me to part with it. However the more and more I talked with Rob and the rest of the staff at AMR the more I realized that these guys aren't just another tuning company who quickly threw a tune together and waited for the cash to come in. These guys knew what they were doing and it shows. They have already put out one revision to the system which is more than any other competitor on the market and they are actively working on more. 

So is it worth it? Well every time I get my hands on a new tune my answer always seems to be yes. I tend to think it's because I only want to review the best and some of the competition who's numbers don't match up refuse to allow us to review their tune. No matter the reason the numbers don't lie. If you asked me I would say this is the tune to run. 

More To Come

AMR is actively working on a Stage 2 tune for the C450. For those of you that are interested we will be reviewing the stage 2 once the system is released. We have some downpipes on the way for review and  can't wait to see what else AMR has up there sleeves.