I've been a little delayed in posting this, but I want to share with everyone my recent time spent with Jerry and Erick from LET. First let me start by saying both of these gentlemen were absolutely first class. It was a pleasure to spend some time with them along with the dyno at my friend's shop. Jerry was in Houston for the weekend, and was joined by Erick and a few others. We spent time dyno tuning a friend's C55 along w/ my C55. Actually, I had Jerry load the same tune into mine that he had developed over the course of 15 dyno pulls on my buddy's car. (Our two cars were equivalent...)

The peak dyno results were elevated slightly, but it was the changes to the area under the curve that made the most difference. My C55 felt more aggressive per the additional low-end torque, and was generally more exhilerating to drive throughout a typical run. It is a relatively known fact there is not a ton of peak power left on the table in the C55's stock tuning, however as anyone should understand the key to a good tune is the "area under the curve", across the entire dyno pull in a normal operating range. This is where we found some room for improvement, and I am very pleased with the results. I can also testify the car has more of a "traction problem" per the tuning --- which is a good problem to have.

I'm not sure when I'll get it back to the track, however I do hope to beat my previous best 13.47 run, and hopefully pick up a little in the mph number as well.

Other benefits of the tune included a slight raising of the rev limiter, as well as raising the 155mph speed limiter by 30%.

Jerry and Erick both were very accomodating to me and my friend. There's a lot of information stored up in Jerry's head, and I am openly endorsing his tuning improvements as being a nice, and relatively inexpensive modification to the C55. His prices are about 1/2 of some of the others who do the same thing, which is certainly a big win in my book!
I'm also eagerly awaiting his upcoming ability to tap into the Transmission Computer (TCM) to make the car shift and react the way it should've from the factory. I truly believe there is some ET to be found there, but more importantly just to make the tranny shift the way it should, while holding the gears a little longer, etc. I'm very anxious for this ability once it becomes available very soon.

Final Summary --- TWO THUMBS UP!
Much thanks to Jerry, Erick, and my friend Jayson who provided the dyno! It was a great day, with good results.

 

Im also in the process of getting my tune , I cant wait!

 

It was my pleasure!!

I enjoyed hanging out with you guys.

We need to put Jayson in your back seat for revenge!!

 

JToups386 - thanks for posting this! Good info and I'm pretty impressed!

 

I too just ordered a tune from LET Motorsports. I should be receiving my ECU back any day and will report back with my impressions.... That being said, I agree with your previous comment. Jerry is a great guy and his responses to all of my email questions where quick and concise.

A great company.

Thank you...

 

Jerry tuned my C55 on the dyno just before Jtoups386. I could definitely tell an improvement throughout the entire RPM range. The TCM programming, when available, will make a huge difference in this cars performance as the factory shifting is inconsistent and far from firm.

I can tell you through my many years of tuning experience that Jerry definitely does knows what he is doing. If you are considering doing this, have no doubt that your car/PCM is in very capable & knowledgeable hands. Jerry does care what results are achieved and is genuinely concerned that you are pleased with the results.

Eric, it was very nice meeting you and thank you for all your help and assistance as well.

 

What are the #'s. Also does that dyno read wayyy lower? bc c55's are supposed to dyno at about 300 rwhp stock.

 

Dyno numbers will vary up and down for many different factors. This was done on a Dyno-Jet, but there are several other dyno brands out there --- and all might read a little differently. Then you also have to consider the outside air temp, barometric pressure, etc, etc. Granted, we can use a corrected SAE number based on the dyno output, however anyone who ever posts their dyno numbers will almost always list their highest rating. It's an ego thing...
The key thing to remember is that all testing should be done on the same dyno for each car, therefore any HP or torque gains will be recorded on the same scale, and the trends will be an even comparison. I'm not so concerned about the actual beginning number, but rather the ending number increases which go above the starting point.

I can tell you that my stock C55 originally made 297rwhp, and with the addition of K&N's, it made 306rwhp (January 2008). Keep in mind these are peak numbers, and when considering the gains attained through tuning, the peak number is the least important to me. If my car makes 307rwhp peak, yet it only does it at 6200rpms at the top of the dyno curve; then that peak number means very little to me unless I can raise the entire powerband upwards across the curve.
That's what Jerry was able to do through his tuning. He increased low end torque significantly, and raised the overall peak number too. However, it was the raised power in the "area under the curve" that made the most difference. We didn't print out the graphs this time so I cannot give you specifics other than what's in my head at the moment, but I can assure you there were noticeable gains across the entire curve.

Also, keep in mind the C55 setup does not allow for the same massive tuning gains as some of the other AMG applications, because Mercedes chose to max out the C55 from the factory more than some other models. For example; my friend's C63 was able to pick up 42rwhp with a computer tune, and gains like that for the C55 are just not realistic per the more aggressive factory tune.

Back to the point at hand --- there are gains to be had in the C55 throughout the normal operating range, whereas the peak number is somewhat irrelevant. Again; if I could gain 10-12 rwhp and rwtq from 2400rpms thru 5500rpms, I'd gladly take that over an additional 20rwhp spike only found at 6200rpms, because my car is rarely going to be operating in that range. I could go on and on with the specifics, but I assume this was enough to make sense for most of our readers.
I will also likely go back to my friend's shop over my Christmas work break, and make a few more dyno runs. This time I'll print the graphs and numeric values to give a better assessment, while comparing them to my original numbers.

In the end however, my good old fashioned "butt dyno" tells me the car feels noticeably different, more aggressive, and the rear tires are screaming at me to stop lighting them up on hard acceleration. The car feels better throughout my operating ranges on the street, and since I will never be on the Autobahn itself, the additional peak number up top will likely never have much use for me. It's all about the "area under the curve"!

Again --- kudos to Jerry and Erick from LET for a job well done! I'm enjoying the car again! And once we do the TCM upgrades, I can only imagine it'll be even that much better.