Originally Posted by amg-jerry

I guess I can only speak about the tunes that I've seen and my personal tune that I paid over $2k for. I bought the Stage I kit (pulley / tune), plus I paid an extra $1k for a custom tune. I sent my ECU to them at least 15 time via overnight delivery to get what I thought was a better tune. I spent over $5k in labor costs with various places to figure out what was wrong with my car. It wasn't making power and was running lean. They said I should be running 12.5 to 1 with my tune, so there must be something wrong my car. I replaced every sensor, fuel filter, injectors, plugs, wires, and paid for a leak down test. After a year of troubleshooting my dyno shop discovered that either MB didn't gap my plugs or gapped them wrong. They were gapped beyone the shops measuring tool. After they were gapped correctly, the car picked up 45-50rwhp.

Now, after months of learning LET's new software, I compared my Renntech file to other tuners files and to the stock software. Turns out the only thing changed in all 5 maps was the ignition timing at part load! They never even touched the injector maps which is why I was running lean! They did change the rev limiter and top speed limiter. This isn't what I was expecting to see. I paid over $750 in shipping costs for this?? I was furious and now I will never send a client there again. I was pro Renntech and even put Renntech stickers on my car.

I guess the saying "If you want something done right, do it yourself." was right on in my case.

I have also had the pleasure of looking at E55 tunes and SL55 tunes from Renntech. Needless to say, they were nothing special and not worth the money.

I (and LET) promise to provide as much information on tuning as possible to better educate everyone. There is nothing special about our ECU's and the tuning is actually easy to understand once you know the basics.

It will be better for everyone if you are educated on what is being done to your car. I have sat down with local members and actually told / showed them what I've changed and why.

If you have any questions, please ask. LET is in the process of bringing a new partner on board to assist me with tuning and to provide their experience. Stay tuned!