How Does The Bmw N54 Compare To The N55?

In nan mid-2000s, BMW launched a caller straight-six motor that would beryllium 1 of nan astir important successful nan brand's caller accumulation history. The N54 was nan German company's first gasoline-powered motor pinch a turbocharger, and not conscionable one. It had two. Just a fewer years aft nan N54 deed nan streets, nan N55 appeared connected nan scene, replacing nan N54 successful respective models.

Was location overmuch of a quality betwixt nan N54 and N55, too nan name? Actually, yes, albeit mostly successful really nan N55 handled turbocharging. Instead of nan copy turbochargers successful nan N54, nan N55 was built pinch a azygous dual-scroll turbocharger. This simplified creation cranked retired arsenic overmuch powerfulness arsenic its predecessor, but did it much efficiently, thereby reducing emissions. It was besides much reliable, correcting immoderate of nan issues that had travel pinch nan N54 while providing nan aforesaid powerful performance, but much efficiently and astatine a little cost.

That ratio came astatine a mini price, however. The N54 is simply a favourite among motor tuners owed to its adaptability. By halving nan number of turbochargers, nan N55 has a somewhat little limit successful position of nan horsepower tin beryllium squeezed retired by adding aftermarket parts. Nevertheless, you tin still tune nan N55 and summation its horsepower importantly complete its mill specs.

The 3.0-liter N54 roared onto nan segment successful 2006, first seeing work in the 2007 BMW 335i. It had 2 turbochargers and could crank retired 306 horsepower and 295 lb-ft of torque, which, astatine that time, was thing to sneeze at. The motor itself was constructed of aluminum and was built pinch a forged crankshaft and rods. It besides had 2 overhead camshafts and 24 valves.

It was besides beautiful cutting-edge for nan day. It featured high-pressure nonstop substance injection, which contributed to its powerfulness and efficiency. The N54 besides included BMW's VANOS adaptable valve timing strategy and physics wastegate control. These features would supply awesome power and optimization of nan engine's performance, but it would besides adhd complexity to nan engine, which typically results successful much that tin spell wrong.

The N54 would extremity up being beautiful celebrated pinch nan tuning community. Aftermarket parts for this motor are plentiful, making it comparatively easy to compression much powerfulness retired of it. According to immoderate sources, tuners tin regularly get upwards of 400 horsepower retired of nan engine, and galore study achieving much than 500. It is astir apt nan tunability of nan N54 that sets it isolated nan most.

For each its innovations, nan N54 had its stock of problems. That's to beryllium expected, since BMW was caller to building mass-produced inline-six state turbo engines. There were kinks that had to beryllium worked retired and issues that had to worked through.

One of nan astir notorious issues was wide high-pressure substance pump (HPFP) failure. This led to a monolithic callback successful 2010 of 130,000 2007-2010 exemplary twelvemonth vehicles pinch N54 engines. The callback targeted HPFPs pinch circumstantial manufacturing codes. BMW would besides widen nan warranty for nan HPFP to 10 years aliases 120,000 miles, which was a bully thing, since having nan dealership switch nan pump pinch an OEM exemplary could costs upwards of $1,500. Of course, that warranty has agelong tally out, truthful anyone who owns immoderate of these cars that did not person nan HPFP replaced would beryllium connected nan hook for nan costs today.

Other communal issues knowledgeable by owners of cars pinch N54 engines would include, leaky substance injectors, a leaky valve screen gasket, c build-up, a failing h2o pump, and a rattling wastegate (here's an explanation of wastegates and really they work). To put it mildly, nan N54 was a small unsmooth astir nan edges.

BMW had been learning from its mistakes from nan N54, and rectified a batch of them pinch its successor, nan N55. Just for illustration nan N54, nan N55 offered 306 horsepower and 295 lb-ft of torque. But it was much reliable, sewage amended state mileage, and fto retired less emissions. One of nan ways it achieved this was done nan summation of nan Valvetronic adaptable valve assistance system, which amended optimized and regulated airflow done nan engine.

The N55 was built pinch a azygous turbocharger, but it was a twin-scroll, branded confusingly arsenic "TwinPower Turbo". This was a lighter turbocharger pinch a simplified design. Still, nan banal group up was capable to crank retired nan aforesaid magnitude of powerfulness arsenic nan N54 pinch its 2 turbochargers, moreover reaching highest RPMs a small faster, though immoderate would opportunity not notably faster. Of course, this simplified creation contributed to nan N55's reliability.

While location were upgrades to hole immoderate of nan problems that came up pinch nan N54, overmuch of nan building was similar. The artifact and caput of nan N55 were made retired of aluminum, conscionable for illustration nan N54. It besides had dual overhead camshafts and 24 valves. And some nan N54 and N55 were 3.0-liter I-6 engines. BMW wasn't trying to re-invent nan instrumentality pinch nan N55, conscionable amended connected it a bit.

While nan N55 improved nan creation successful tons of ways, it did not cleanable it, and nan newer motor came pinch its ain group of problems. One point it didn't hole was nan leaky valve screen gasket. In fact, it was 1 of nan newer engine's astir communal issues. Even nan valve screen itself was prone to get cracks erstwhile nan odometer approached six digits. Another problem that wasn't fixed was nan failure-prone h2o pump. But this was an rumor crossed BMW engines.

One weakness was nan VANOS valve lifting system, which is an physics VVL system, and useful successful conjunction pinch nan N55's Valvetronic, a VVT system. (Here are nan differences betwixt VVT and VVL.) Not only was nan N55 prone to issues pinch nan solenoids, but the bolts successful nan VANOS strategy successful nan early years were faulty, arsenic well, truthful overmuch truthful that location was a recall. Another communal problem was nan lipid select lodging gasket (OFHG), which tin deteriorate complete time, causing lipid leaks.

Of course, tuners would opportunity that nan N55 fell short successful tunability. With nan correct aftermarket parts, you could get complete 400 horsepower retired of nan engine, but that wasn't adjacent nan capacity you could eke retired of nan N54. For nan astir part, nan tuning organization prefers nan older N54.

We've already pointed retired a mates of differences betwixt nan N54 and N55. The N54 utilized a group of copy turbochargers to get optimal power, whereas N55 streamlined nan creation by utilizing a azygous dual-scroll turbocharger. Both copy turbochargers and azygous dual-scroll turbochargers are designed to reside nan aforesaid rumor — back-pressure interference, which is erstwhile exhaust from aggregate cylinders clang against each other, reducing nan easiness of airflow. Twin turbochargers and azygous dual-scroll turbochargers onslaught this by dividing nan exhaust from I-6 cylinders into 2 exhaust channels, 3 cylinders into one, nan different 3 into another, reducing back-pressure interference.

The problem pinch copy turbochargers is that location are 2 of each part, meaning doubly arsenic galore parts that tin break, fail, aliases deterioration out. The simplified creation of nan azygous dual-scroll turbocharger intends that nan only parts that are duplicated are nan exhaust channels aliases scrolls. There is conscionable 1 turbocharger for some channels, making for a much businesslike design. Besides ratio and greater reliability owed less parts that tin fail, nan azygous dual-scroll creation tin nutrient much torque astatine little speeds and tin acquisition little turbo lag.

The downside to having conscionable 1 turbocharger alternatively of 2 has to do pinch tuning. You tin only get truthful overmuch other horsepower retired of 1 turbocharger. Logically, then, you tin get much horsepower retired of 2 chargers alternatively of one. Still, some nan N54 and N55 person a batch going for them.