[jhbodle]

The 330i has a valve/flap in the exhaust to increase the sound coming out of it. Is it possible to fit this to a 325i (euro spec)? What parts would I need?

If not, do BMW make a sports exhaust?

[NoMods]

tagged for interest - i noticed the flap when washing my 330 also, does it improve performance or only noise?

[rwwong]

huh? Where's the flap?

[E90Fleet]

Its to decrease the noise at idle or low revs, not increase it

[jhbodle]

Originally Posted by E90Fleet

Its to decrease the noise at idle or low revs, not increase it

Does that mean that to get the noise of a 330 all I have to do is change my exhaust for a 330i one? From the cat back?

Or have BMW released a sports exhaust yet

[E90Fleet]

Originally Posted by jhbodle

Does that mean that to get the noise of a 330 all I have to do is change my exhaust for a 330i one? From the cat back?

Or have BMW released a sports exhaust yet

Only way you would get the noise of a 330i is by buying a 330i

The 2.5L wont ever sound like the 3.0L engine.


There is no BMW sport exhaust.
Closest thing would be a AC Schnitzer one

[Stronie]

Originally Posted by E90Fleet

Only way you would get the noise of a 330i is by buying a 330i

The 2.5L wont ever sound like the 3.0L engine.


There is no BMW sport exhaust.
Closest thing would be a AC Schnitzer one

Really? !!!! Cause I thought that the 325i had the same engine N52, which is a 3.0L.

[younghov85]

Originally Posted by Stronie's BMW

Really? !!!! Cause I thought that the 325i had the same engine N52, which is a 3.0L.

The are the same engine but the 330i has a 3 stage air intake mainfold.

[Stronie]

Also a different programmed ECU, but that has been beatin to death.

[E90Fleet]

Originally Posted by Stronie's BMW

Really? !!!! Cause I thought that the 325i had the same engine N52, which is a 3.0L.

Yes, really

You may have noticed the original poster is from the UK, and in Europe the 325i is a 2.5L

So to you

[E90Fleet]

Originally Posted by younghov85

The are the same engine but the 330i has a 3 stage air intake mainfold.

Only in the USA and Canada
Rest of the world has a 2.5L 325i

[younghov85]

Originally Posted by E90Fleet

Only in the USA and Canada
Rest of the world has a 2.5L 325i

In the BMW 3-series E90 brochure they state that both are 3.0L but one has 255hp and the other has 215. Then under they say also that the 330i has a 3 stage intake manifold while the 325i has a single intake manifold.

[E90Fleet]

Originally Posted by younghov85

In the BMW 3-series E90 brochure they state that both are 3.0L but one has 255hp and the other has 215. Then under they say also that the 330i has a 3 stage intake manifold while the 325i has a single intake manifold.

Correct, in the USA and Canada ( as I said above )

The rest of the world has a 3.0L 330i with 3 stage intake and a 2.5L 325i also with a 3 stage intake.
And europe will soon get a 330i thats 3.0L and has Direct Injection

[E90Fleet]

If you want to read about it being 2.5l go to www.bmw.co.uk and look up the 325i specs, or any other non-north american countries BMW site

[jhbodle]

Originally Posted by E90Fleet

Only way you would get the noise of a 330i is by buying a 330i

The 2.5L wont ever sound like the 3.0L engine.


There is no BMW sport exhaust.
Closest thing would be a AC Schnitzer one

Bah, that's not good.

Out of interest, what makes the 330i sound better then? They are both 6 cylinder N52 engines, both have 3 stage intakes (in UK spec) - what does the 3 litre have that the 2.5 doesn't?

[E90Fleet]

Originally Posted by jhbodle

Bah, that's not good.

Out of interest, what makes the 330i sound better then? They are both 6 cylinder N52 engines, both have 3 stage intakes (in UK spec) - what does the 3 litre have that the 2.5 doesn't?

Larger engines generally sound better.

I find a 325i driving past you at low RPM sounds better than a 330i , probably due to the valve on the 330i.

But when they both floor it, the larger engine sounds better, not that the 325i doesnt sound nice.

Remember AC Schnitzer is partly BMW owned and usually doesnt affect warranty in the UK as far as I know, and they have some very nice exhausts

[ksfrogman]

In the U.S., the E90 330 and E90 325 share the same engine displacement. One of the major differences in HP is the three-stage induction system of the 330 vs the standard 325.

At idle, the exhaust valve on the right rear exhaust pipe is open. I know this because I can see it open when I'm idling the car. Some believe the purpose of the valve is to increase torque at certain RPMs, but most believe that it simply closes at certain RPMs to mute the sound somewhat.

I also heard that it closes only at a certain RPM in second gear. This makes sense because I imagine there are certain maximum sound standard a manufacturer has to stay within to meet a particular country's regulations. I was thinking about plugging this line up tonight and driving to "hear" a difference.

The most scientific way would be to hook the line up to a vacuum gauge via a long vacuum line that leads to the driver's seat. In this way we can see when it the solenoid triggers it to close.l

[E90Fleet]

BMW's technical training says its only for sound, especially for when cruising down the higway at a low RPM.

It has nothing to do with engine torque. Hence why places like AC Schnitzer dont put it on their exhausts.

[ALPINE6SPD]

can you remove the flap to increase sound fleet?

[hamo26]

well this is off topic, but can you change a 325 single stage intake to a 330 3 stage intake?

[E90Boy]

Originally Posted by hamo26

well this is off topic, but can you change a 325 single stage intake to a 330 3 stage intake?

I was thinking about that myself. The 325i ECU will adapt to the new manifold right? I called the dealer before and was told $800+ for the 330i 3 stage intake manifold. I've been hoping for someone to try this mod out to see the results.

Who's taking the plunge? I'm sure 325i will get some good power from this mod.

[hamo26]

someone with knowledge please answer us! if this works.. im gonna stay with my 325 order instead of waiting for the 328 sedan.