Hey guys... well I have had my 2008 335i e90 (Sport Pkg, with Steptronic Trans) (Thanks to Brecht BMW) just two weeks now... 700 Miles... and decided to take her to the dyno.

Well first off.. just 5 days ago... 1 week old... 600 miles... I took her to the drags.

IMO 100% Stock... but truth be known... I have a bb in the Exhaust Valve Vacuum hose, and a K&N Air Filter.

Car ran 13.50@103.5 MPH On Factory RFT's w/ Factory Pressures.

So then tonight... took her over to XTREME Motorsports in Tempe, AZ to do some baselines before we chip her & add an exhaust!

I was very impressed with the numbers... but decided to add something I think we all would like to know! Not what a K&N does AFTER but WHAT A FACTORY FILTER DOES AFTER!!! :D

So... I did two pulls with a K&N and full tank of 91 Octane Chevron Fuel...

Car Put down 279 RWHP and 289 RWTQ!!! I was VERY PLEASED!!! EXTREME'S Dyno is typicall a percent or two lower than most Dyno Jets...

Air Temp was just above 60'...

Then... I pulled the K&N... and Dropped in the Factory Filter!

Car put down 278 RWHP and 286 RWTQ!!!

I felt this was much more 'real world' then... a slight 'lean' trick... buy changing from the Paper Filter to the K&N!

Anyways... I couldn't be happier seeing this bone stock Steptronic Car... laying down these kind of numbers!

Thanks BMW! & Thanks BRECHT BMW for a great ride!
Dave

Anybody have a way to post pics? And I can email the Dyno sheets? (I don't have enough posts yet!)

Good results indeed, but the BB in the E90 will cause a nasty drone at freeway speeds and does nothing for power if it's enabled or disabled.

Yeah, I agree... Honestly... the car is so quiet... I don't mind it... at least I can hear 'Something' :D

Isnt there a something called a break in period for brand new cars that you should have at least 1000 miles on it before you take it to high rpm's?

Yeah... people seem to buy into that... I never have... This car saw 130 w/ about 75 miles on it... You have to break them in like you plan on driving them! I've never had a car use oil, etc... It's the only way to the seat the rings! ;) (I beleive)

1,200 miles? (that's what our book says)... for 4,000 RPMS??? OMG!!! Just put a gun to my head if that's what I had to do! I wonder how much carbon get's built up over 1,200 miles... 'cruising' at less than 4,000 RPMS!

But... everyone has there own theory's on what's best for their cars.

Peace,
Dave

Seem to recall hearing 15% was the conversion factor for RWHP to flywheel, but I also saw a pretty good test on a series of corvettes that indicated 11.47% across a large range of HP. I suppose it's probably different for every set-up given the different power losses due to design variations, etc. Does anyone know what the 335's conversion would be? At 11.47, the car tested on this thread would be at 310-311HP bone stock, which is reasonably above what most consider conservative factory claims of 300.

How does this all work with torque?

Forgive me if this topic has been beaten to death elsewhere...

12% to 18% seems to be the norm... lower for Manuals higher for the Auto's. It seems like this cars Auto is pretty efficient, I'd say 15% or so... at that rate... looks like this stocker is making 330 HP & 340 TQ!

Lovin these 335's!

Dave

Congrats on the car! The boys at Brecht are great!! Did they try to sell you a Turbo Tuner? they have moved a bunch of those for us.

Have fun and keep us posted on your results!

Happy Holidays to all

Jeff
Eurobahn
{ask about holiday specials}

Seem to recall hearing 15% was the conversion factor for RWHP to flywheel, but I also saw a pretty good test on a series of corvettes that indicated 11.47% across a large range of HP. I suppose it's probably different for every set-up given the different power losses due to design variations, etc. Does anyone know what the 335's conversion would be? At 11.47, the car tested on this thread would be at 310-311HP bone stock, which is reasonably above what most consider conservative factory claims of 300.

How does this all work with torque?

Forgive me if this topic has been beaten to death elsewhere...

The conversion rate will differ from car to car and transmission to transmission. Certain transmissions have less parasitic loss than others, for example, automatic transmission (of old) typically lose another 10% on top of what manual transmission would lose, and manual transmissions typically lose between 10-15%.

Here's a pretty comprehensive list of dyno numbers done at the same facility under the same test conditions for a wide variety of cars. Gives you a baseline indication of what driveline loss is for each individual car tested.

http://www.rototest.com/index.php?DN=33

For example, the 335i coupe auto tested shows a power loss of 6%, so their test figure shows the transmission on this particular 335i is ~94% efficient, or their wheel HP numbers are 94% of what BMW claims the crank power to be. A 6% loss on an automatic is pretty impressive, either the newer transmission/driveline are better designed or BMW is significantly under-reporting all their HP figures.

Keep in mind their dyno tend to test a little higher than competing brands (look at the figures for the Z4 3.0Si and Z4 M for example). I would probably tack on another 5% to their loss figures to get closer to what other dynos would typically show.

Hi Jeff! Yes they did... they just said to call them once it has 1200 miles on it! But they did take me to the parts dept... and open a box up for me!!! I will be ordering one very soon! Great bunch of guys there! And I love the ease of your SSTT.

Thanks again!

Hey! I can add pics now! Here is the Dyno Graph!
Peace,

These cars are such monsters. I need to start getting back in the game if I want my "old" cars to keep up with all of these new ones haha.

-Don