Hello All! Long time lurker in this forum, and recently decided to join the group. Before I begin - I am a long time BMW owner, with past cars to include a E46 M3, a 2007 E93 335i, a 2013 E93, and my current stable of BMW's - E90 335d and a E88 135i. This post is specifically related to the (M57) 335d, and why I absolutely LOVE this platform.
I have always owned a diesel car/truck/SUV, mostly of the VW TDi variant. When VW decided to try and cheat the EPA - I had the opportunity to sell back my TDi and buy a BMW 335d. Every TDi I own has been tuned for maximum power and torque.
Little background on the 335d/X5d, and details specific to my 335d. The E90 M57 335d was sold in the US from 2009-2011 - and unfortunately, a MT was never offered in this car here. Less than 10,000 M57's 335d's we sold here in the US during this period; however the M57 was used globally in various platforms and even in the X5d here in the US. Stock hp and tq number's were ~265/425 respectively. Fuel mileage was rated at 36 mpg's for the highway. The M57 runs a compound (Sequential) turbo set-up with a HP (small) turbo to spool quickly while the LP (Large) turbo build boost. A changeover valve regulates when the LP takes over. Unlike the N54 and N55 - the turbos are integrated in such a way that changing out to larger turbos or even a single is a huge challenge (more on this later).
Unlike the N54 and N55 335i, the lack of demand or popularity for a diesel 335, as well as an iron fist EPA policy pushed BMW to stop offering a diesel 335 here in the states. Many of the problems with this platform are directly related to the Diesel Particulate Filter and the SCR systems mandated by the EPA. The use of DEF in diesel cars/trucks is not uncommon with modern diesel's; however the exhaust system completely chokes this car and causes issues that can drive owners to hate diesel cars. Carbon cleaning is another issue from the DPF/SCR systems. Every diesel BMW must have a carbon cleaning and walnut blasting around 80k miles or so. Once the car is cleaned (and deleted, see below) - you never have to worry about this again. Or use DEF....
BMW does currently sell the N57 based 328d here in the US; however it is not a worthy successor to the M57 IMO.
Now - on to the good stuff!! Why do I LOVE the M57 so much...? For starters, it's different. Unlike the N54 and N55 - the M57 has never really been pushed to it's full potential. Over the last 2 years, this has drastically changed. These cars are now being supported by a handful of knowledgeable tuners and part specific shops. Additionally - VW bought back most of the 2.0 (485,000 to be exact) and 3.0 TDi's here in the US (Mine included). This cash heavy group of former diesel owners began to research viable options for replacements and a used 335d could be had for $10,000 to $16,000. It was really a perfect storm of events that led to a quick explosion of 2nd generation 335d owners who are looking for an economical car with a superb delivery of power and balance.
I sourced my 335d just before VW bought back my VW 2.0 TDi. The 335d was bone stock when I purchased it (see pic). I knew before I purchased the car - I have every intent to completely delete all emissions, straight pipe the car and have it tuned. In many states - other than California - diesel cars/trucks are not emission tested. Here in my state, I only have a safety inspection
On stock turbos, upgraded FMIC, straight pipe exhaust - these cars can make around 380 whp and about 580-600 wtq. Not bad for a diesel car! The best part - with the Emissions deleted, the car can get upwards of 45 mpg's! For the readers benefit - the almost INSTANT torque this car makes is addictive. Not satisfied with this power level - I decided to go all in for a big power. This included:
Upgraded my turbos (Hybrid)
Snow Meth kit with a 1200 cc nozzle - running a conservative 65/35 Meth/water mix.
xHP Transmission stage 3 tune
Custom Dyno tune running ~ 45 psi
Upgraded FMIC, solid piped
Wavetrac LSD, Diff Brace, Power Flex Diff bushings
Custom CIA
Bilstein Coilovers
Modified Injectors
Hamilton Springs
HPFP
All of this brought the car to just over 500 whp and ~ 690 wtq....and many hurt feelings at the track and down in 'mexico'.
I wanted more power and wanted to see what it could really make. Understand - a couple tuners had already pushed 335d's to levels of 475-500 whp and 680-700 wtq during this time, but no one had pushed the platform beyond 515 whp. What I learned - it's a back pressure limitation with the design of the M57. Our cam profile has been referred to as a 'tractor' profile. While the N54 has made a HUGE step forward with top and bottom mount single turbo's and do not really have the need to modify the cam profile for big power - that's not the case with the M57. Having a 5k red line - power cannot be made at 6k-7k rpm's. The ability to reduce back pressure and open the air flow is critical for the M57 to make more than 500/700. Secondly - aftermarket turbos and turbo kits don't exist.....yet
As a result of some expensive trial and error, and switching tuners - I am working on a complete build for my 335d. Upgrades as follows:
Forged Rods that are 10mm longer
Steel one-off monotherm pistons with the wrist pin moved up 10mm - ceramic coated with anti friction coating
Fully polished/ported head, and gasket matched hone of the exhaust manifold
ARP head, main, and rod bolts
Custom cam profile for lift and duration
Custom EFR LP turbo set up
The goal here is ~ 650 whp, as well as a yet to be determined 750+ wtq number.
Anyway - I'll add some pics and a couple videos for the group later tonight.
Ask any questions - I enjoy a good discussion.