Does anyone know the differences in the engines between the 2008 facelift 523i and the older versions? If they are all the same engine block and same engine capacity, why cant we just remap the ECU to acheive the same bhp as the 525i? Anyone have any ideas?

 

Simply put: The 2006 model had a 2.5 liter engine with 177 BHP. In the LCI upgrade the engine was overhauled an got a direct injection system managed by a high pressure pump reaching 1800 psi (or is it bar?, I never get that straight) and now has a power output at 190 BHP.

So, the block and capacity is the same, but otherwise a much changed engine.

 

Well i don't think it is that easy to just up the ECU.
I think the 525d and 530d share the same engine now so why would anyone buy a 530d if this was possible. Just get a 525d and put a 530d ECU in it, wishful thinking !

 

ok. then would it be possible to install a high pressure pump to replace the exisiting one to boost the bhp or are there many other things that need to be changed? Or is it not as simple as that? Dont think BMW would waste tonnes of money modifying their engines for the same model.

 

THe 523 LCI version and the 525 LCI indeed use the same engine N52n ( i.e. N52K) 2.5liter version. the N53 was not released in asia becasue of sulphur content in fuel would harm hte the higher temp catalytic converters. Now to the question of remapping the 525 engine uses 2 DISA adapter; take them to be valves in the intake manifold while the 523 uses only one. In principle there is no difference and a qucik check at real oem.com will return the same part numbers for the 2 cars even the DME ( ECU in BMW lingo ) is the same. Each hoever is mapped according to the VIN. So if you can find someone to remap the ECU of a 523 with the 525 settings then it would work. However you cannot swap the 525 ECU directly since hte VIN numbers of hte cars will differ and hte electronics will not allow the engine to operate. Go to E90 post.com and check out the forum of doing the same excercise with the US 325 and 330i which again use the N52B30 engines. Swapping the intakes is the easy part, however getting to reprogram the 325 ECU to stock 330 setting is a challenge. aparantly a guy in Canada has managed to remap his 323 to 325.

Summary: Iti s possible if you can get the ECU reprogramming done (BMW wont do it) and yes there is no need to change the pump etc for this since the engines are absolutely identical. The new 523 ius rated at 190bhp vs, the older one rated at 177bhp; there are quite a few modification between the old N52 and newer N52K engines, in Europe they use the Direct injection version N53 version with same power rating of 190 bhp. hope this helps.

I do not think you can draw parallels to the diesel engines which are not avaialbe in Singapore anyway....

 

if the "LCI" refers to the later 2007 released cars like ours - the 525 is 3litre 218bhp. It gets the same changes from old 525 as the new 523 did as far as I know.