[TomRat]

Hi All,

I'm looking at doing some performance mods to my 2010 323i (E90.) Alot of forum posts I read about this car either refer to the UA 325i or 328i versions (the N52B30) which was a 3.0L N52, however my car has a 2.5L N52K (both 323i and 325i in aus had a 2.5L known as the N52B25) and I was wondering what mods are interchangeable with the US 3.0L version and what mods are available to me?

I was looking at doing the OEM performance exhaust (not really for more HP but dat noise) as well as an intake manifold (will the aus 330i manifold fit?), tune, Dinan ram air intake and maybe a BMS powerbox, however I hear Active Autowerke has a better version of this?

Can anyone please help me out with what mods will work on my 323i?

(Please no "just buy a 335" comments please, I'm doing what I can with what my license permits me to own, of which a 335 is not included)

Thanks!

[tlow98]

I'd check in over on Piston Heads or something similar. They had the same version of your car. Not many in the US are going to be able to help.

Ideally, you could do the following:
3 stage intake
MILV shims
Headers
Tune

What were the stock power ratings on your car?

[hassmaschine]

All of the mods will be compatible - they will just have lower/different results.

Does the 2.5l N52 have a smaller bore or a smaller stroke? If its the latter - I'd look at mods that make power at high RPM, like a shorter diff ratio combined with something like the MILVs. The N52 is already sort of a 'baby' S54, it makes power at a relatively high RPM which is also a strong suit of an engine with a relatively shorter stroke.

[Ali-E90]

I have a 323 in canada (2.5 N52) and often have the same issue looking for parts since US never got anything but the 3L N52.

Pretty sure the 323 already comes with the 3-stage intake manifold. The exhaust options from a 328/330 should fit, but I think headers are a slightly different size.

Also, no need for a powerbox AND a tune, I'd recommend finding a good tune and forgetting the powerbox.

If you like sound, maybe consider an air intake also. This should also be interchangeable with the 3L N52.

[Eddien123]

Tune, intake manifold (if not already 3 stage) and exhaust (headers if you can swing it). Unfortunately, as reliable and well these engines put together, the tuneability of them is not as present as the turbod bmws. However there is still things that can be done but just dont expect much.

[TomRat]

Originally Posted by Ali-323i

I have a 323 in canada (2.5 N52) and often have the same issue looking for parts since US never got anything but the 3L N52.

Pretty sure the 323 already comes with the 3-stage intake manifold. The exhaust options from a 328/330 should fit, but I think headers are a slightly different size.

Also, no need for a powerbox AND a tune, I'd recommend finding a good tune and forgetting the powerbox.

If you like sound, maybe consider an air intake also. This should also be interchangeable with the 3L N52.

Oh okay, sounds like exhaust, intake and tune for me, thanks for the help!

[max_330i]

Originally Posted by TomRat

Oh okay, sounds like exhaust, intake and tune for me, thanks for the help!

You got some good responses from tlow and hass as well. They're talking about engine modifications you might not have the means to purchase or install, but I would definitely research their suggestions. Exhaust and intake will have a really miniscule impact on the actual power that your car puts down to the ground... it will sound like a beast and perform somewhat better, but not leaps and bounds.

[TomRat]

Originally Posted by max_330i

You got some good responses from tlow and hass as well. They're talking about engine modifications you might not have the means to purchase or install, but I would definitely research their suggestions. Exhaust and intake will have a really miniscule impact on the actual power that your car puts down to the ground... it will sound like a beast and perform somewhat better, but not leaps and bounds.

Sorry for slow reply, but thanks for your advice, definitely noted!

[Twoforty]

Hi TomRat. I am in AUS with the 2.5 litre 325i.
Mine has the 3 stage inlet manifold but I very much doubt that yours has (that's why it's called the 323). So that is one important upgrade you could research.
My only mod is the performance exhaust. You won't find cheap and easy power upgrades.
So be content with improved sound is my recommendation.

[scanspeak]

I took a close look at my 323i (Australian) intake manifold.
It appears to have the top intake actuator but doesn't have the lower one (located underneath the runners).
So it appears to me that this model is a 2-stage system ??
Does that sound correct?
If so, that is great news as it means I can potentially upgrade the manifold for a 3-stage type like this :

https://www.ecstuning.com/b-genuine-...1617559523kt2/

https://www.turnermotorsport.com/p-3...ftware/?pdk=Ag

http://www.**********s.com/bmw-n52-N...ersion-kit.htm


Pelican Parts instructional video .

http://www.pelicanparts.com/BMW/tech...eplacement.htm


I used this video as a reference.

[hassmaschine]

yes there was a 2 stage manifold as well, we never got it in the US but everyone else did.

[scanspeak]

323i intake manifold (note how item 2 adjuster is fitted but it does not have item 3 adjuster).

http://www.realoem.com/bmw/enUS/show...diagId=11_3756


325i intake manifold (has both adjuster units)

http://www.realoem.com/bmw/enUS/show...diagId=11_3756



The 3.0L US version has a different model number so the upgrades from ECS tuning, Turner Motorsports etc probably won't work.

[Chad053]

Hi all, I understand that this forum is talking 323 to 325 and that the 325 already has the stage 3 manifold.

However, I read online of people upgrading their 325 to the 330 stage 3 manifold.

My car is producing 160kw and the 330 produces 190kw and apparently the stage 3 manifold has something to do with it just like the 323 vs 325 in Australia.

So I'm wondering, given that I already have the stage 3 manifold in my 325, could I flash my car with the 330 flash and expect the 40hp power increase?

[hassmaschine]

No. Your 325 has the 2.5 liter block. In North America, BMW sold the 325 (and the 328) with the same 3 liter block and head as the 330i, but with a single stage manifold and a detuned calibration.

[Ali-E90]

To echo was Hass said, only 325 models with a 3L motor (US, Canada) can benefit from the intake manifold swap and tune benefits discussed.

Yours is likely the 2.5L which already has the 3 stage. Your power is down because of smaller engine displacement, not because of the intake manifold.

[neilvan]

Originally Posted by Chad053

Hi all, I understand that this forum is talking 323 to 325 and that the 325 already has the stage 3 manifold.

I'm not sure on the HP of your car but some euro 325's (3 stage) has 215hp vs 201hp. I'm sure you could flash up to that.

As well the 3.0L 3 stage mani has larger volume runners than the 2.5: 3 stage so there might be some benefit there as well.