Although I did not have time to take the car to the dyno beforehand, I ran the car last week for the Wednesday night last test and tune. Here in central Ohio the weather was almost as perfect as you can get. Upper 70's low 80's with sun heating up the track. Humidity was low for this time of year in the 43% range. Usually it is much much higher than that. So, there could be no blame put on the weather. This time, I had the fuel down to about 61 miles to empty at the start. It would end up after four passes saying it has 35 left. In short, much less fuel in it than the previous time.

1st pass:

60 ft - 1.830
330 ft - 5.054
660 ft (1/8) - 7.727
@MPH - 92.09
1000 ft - 10.024
1320 ft - 11.973
@MPH - 115.23

2nd pass:

60 ft - 1.840
330 ft - 5.070
660 ft (1/8) - 7.744
@MPH - 92.15
1000 ft - 10.038
1320 ft - 11.990
@MPH - 115.54

3rd pass:

60 ft - 1.833
330 ft - 5.060
660 ft (1/8) - 7.732
@MPH - 92.21
1000 ft - 10.024
1320 ft - 11.972
@MPH - 116.04

4th pass:

60 ft - 1.829
330 ft - 5.057
660 ft (1/8) - 7.732
@MPH - 92.07
1000 ft - 10.028
1320 ft - 11.980
@MPH - 116.01

With the software and intake the car picked up two tenths (.2) of a second or 4 car lengths with an additional 2 more MPH. At the end of the track the car was almost three tenths (.3) of a second faster or 6 car lengths with 4 MPH more. The car seems to make more peak power rather than just a solid 40 whp gain throughout the rev range. The dyno will tell the story about the trap speeds and top end power increase. Renntech software seems to make all top end power. I have had other applications where software alone will net you a half of a second or more in quarter mile times (S3, S4 etc). Not the CLA45 in this case. My expectations were 11.70's near 118 MPH. Given the weather and the limited weight in the car. Not going to happen unless it makes more power or puts it down better at the launch. A mid 1.8 second 60 is alright. A tenth faster at the start will make the car two tenths (.2) faster at the end. That would be a huge difference!

After all this, would I recommend the Renntech over others? Depends on what you are wanting. Previous experiences on other platforms, those cars picked up way more with the software tune. This was a bit disappointing. Drivability nothing has changed except it is a bit more frantic on the top of the rev's, but otherwise feels normal! Having others give their experience with other tuning solutions would be beneficial. For the amount I spent ($2,100 plus installation of the sensor harness $700= $2,800) to net almost three tenths is laughable and would not do it again. I will email Renntech and see if they can adjust the tune in the car or not. If they can, that might make all the difference. As it sits, I would pass at this point for the price vs. performance aspect. The intake though, for sure. It probably helped it breathe better on the top end. Eventuri claimed almost half the hp of the software anyway!

Sorry, no video this time. Fire away if you have questions.

Stock drag racing thread on the forum: https://mbworld.org/forums/cla-45-am...1-4-times.html

 

Would have been nice if you were able to test the car stock for a baseline. Either way tho... it's good to see your feedback. I have a RaceChip device from my previous car that I was thinking I was going to get reprogrammed for my CLA45. I'm convinced the Renntech is just a repackaging of the RaceChip device. Sounds like it didn't make much of a difference... so I probably won't bother installing the RaceChip on my CLA45. Still eager to see your dyno results.

Did the Renntech device change how the power was delivered? Because when I put it on my Audi... not only did it add more power but is also changed how the power came out from the engine over the rev range.

 

@crester I did! At the end of my post I shared the original stock 1/4 mile times of my car. Link is here https://mbworld.org/forums/cla-45-am...1-4-times.html

As for the power delivery, feels the same. Rush at the top end. Seat of the pants, hard to tell until the tach is to the right! I have had APR tuned Audi's before and I know what you are referring to about the difference in power delivery/band. After talking with Renntech on the phone the other day, they informed me that the fuel level was likely too low causing the fuel to slosh away from the fuel line possibly causing some knock. They recommended at least a half a tank of fuel in the car. I have experienced this before with my Syclones. Another race is the 23rd of September, might try to see what happens.

Forgot to mention, here in a Ohio we have 93 octane.

 

great points to mention