SL-Class (R231) 2013 on: Discussion on the SL550

SL/R231: SmartTop Install and Dyno at European Auto Source (EAS)

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Old Jan 22, 2014 | 01:29 AM
  #1  
persian54's Avatar
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SLk300; S500; BMW 335i.
SmartTop Install and Dyno at European Auto Source (EAS)

Hello!

I'm not too new to this forum, but I'm not too much of a poster (more of a lurker here)


But I'm a very active member on Bimmerpost.com (I have over 15k posts). That is because I've had 4 BMWs in the past 4 years:

2009 E93 335:



2009 E89 Z4 35i:



2011 E93 M3:



2011 E89 Z4 35i:




Safe to say I like my convertibles.


Anyways, I decided to change things up a bit and picked up a 2014 R231 SL550 on Xmas Eve, bit of a present to myself:



I told myself I wouldn't do much to the car, as I went a bit excessive with my previous cars (I spent ~$50k+ on the BMWs, mostly on the M3)

EAS has always been the shop I go to and trust. I live about 75 miles one way, but I always make the trip. Tom, Steve and the whole crew there do an outstanding job.

I DEFINITELY recommend the SmartTop! I've had one on all 4 of my BMWs and knew I needed it on the SL. It allows for one touch operation of the roof as well as one touch operation using the key (no more needing to wait for it to close..or open..). It allows you to operate it while moving, which is useful if you get stuck at a light. However, the SL is pretty quick so I haven't needed to use this particular feature (yet at least)

Here is the post EAS made on my car:
http://www.europeanautosource.com/in...-the-dyno.html

While I was there, I also had a dyno done just to see how the car does.





Here is a link to the video:


Factory specs are 429hp, 516tq right?
I was pleasantly surprised with the power results:



About ~410whp and ~460wtq
It shows that the engine is definitely underrated using manufacture's specs (the torque is in line, but the crank power is definitely more than 429)

I'm very grateful for the work the guys at EAS did. I'm actually going back this friday so they can hardwire my radar detector.


Regarding the power..I am contemplating getting a tune… The Weistic I've heard can give an increase of ~120whp and ~150wtq!
That would push the torque of 600w!
Does anyone have any experience with this (or any tune) on their SL550?

I would love to hear any inputs.

If anyone also has any info on 18 in wheel specs, that would be great! I want to take this to the track from time to time (until I get a real track car…), and would love more info on 18in wheels so I can run RS3s and similar tires.


Thank you

Last edited by persian54; Feb 11, 2014 at 09:47 PM.
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Old Jan 22, 2014 | 06:07 AM
  #2  
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sl550
I'm confused. The factory spec is 429hp and 516ft-lbs. Your best car run was 410.83hp and 462.55ft-lbs. Both of your car numbers are well under the factory specs. Why are you "pleasantly surprised".
Darts
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Old Jan 22, 2014 | 07:59 AM
  #3  
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From: Central Texas
2022 AMG SL63
Originally Posted by rmarshall5
I'm confused. The factory spec is 429hp and 516ft-lbs. Your best car run was 410.83hp and 462.55ft-lbs. Both of your car numbers are well under the factory specs. Why are you "pleasantly surprised".
Darts
Dyno measures at the wheel, while factory numbers are at the crank. There are loses in the transmission (transmission + drive shaft + differential, etc.) between the engine and the wheels due to friction, so one would expect lower numbers than he got at the wheel if the factory numbers at the crank were present.

Typical hp loss with an automatic is 22% between the crank and the wheels. I've seen numbers as low as 20% and as high as 25% for well set up engines and drive trains which I assume our SL's are.

Last edited by Centexhokie; Jan 22, 2014 at 08:06 AM.
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Old Jan 22, 2014 | 10:27 AM
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I got it. Thanks for the explanation.
Darts
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Old Jan 22, 2014 | 10:46 AM
  #5  
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From: Central Texas
2022 AMG SL63
Originally Posted by rmarshall5
I got it. Thanks for the explanation.
Darts
You're welcome. Have a great day.
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Old Jan 22, 2014 | 12:33 PM
  #6  
persian54's Avatar
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SLk300; S500; BMW 335i.
Originally Posted by rmarshall5
I'm confused. The factory spec is 429hp and 516ft-lbs. Your best car run was 410.83hp and 462.55ft-lbs. Both of your car numbers are well under the factory specs. Why are you "pleasantly surprised".
Darts
Yes, as stated above, wheel horsepower and crank are quite different.

Manufacturers report crank since it's always higher, thus it looks better for marketing

Though recently, the trend seems to be where they underrate their cars.
The new bmw M5 is another prime example

Wheel horsepower and torque is what really pushes the car. Crank horsepower is, in a way, meaningless for actually driving
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Old Feb 11, 2014 | 09:44 PM
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SLk300; S500; BMW 335i.
So after looking over my E class and noticing it had a bunch of rock chips and other imperfections, I decided to go to Unique Auto Films to get a clear bra done.

They had tinted my E class, so I was familiar with their work. I checked out their work on a couple of my friends' car so I knew I could trust their work.

I decided to go with their Premium Package. If I recall correctly it's the Xpel Ultimate film.
It covers the full hood, fenders, bumper, side mirrors, rocker panels, and A-pillars. 3M on the door edge to protect the doors when people open my door without paying enough attention...

I decided with the Xpel Ultimate since I heard it has self healing properties so any rock chips I'll get after tracking will go away on their own. It's also never supposed to bubble or peel so I'll be set. It'll help give me paint protection and less headache when I turn the car in for a SLS (hopefully..)

They did a great job on the install. At first I was worried I would see a lot of lines and whatnot but it turned out amazing.

I highly recommend them. Just make sure you bring something to do if you decided to wait. Otherwise I'm sure they can help shuttle you somewhere nearby.

Pictures:





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Old Feb 14, 2014 | 04:52 PM
  #8  
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Dynojet Facility, Anaheim CA
Always a pleasure. Time to get started on this build!

___________________________________________

Tom G. | european auto source (eas)
email: tom@europeanautosource.com • web: www.europeanautosource.com • tel 866.669.0705 • ca: 714.369.8524 x22

GET DAILY UPDATES ON OUR BLOGFACEBOOKYOUTUBEFLICKRINSTAGRAM

Last edited by EAS; Feb 14, 2014 at 04:55 PM.
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