You would assume it had been designed to be that length for a reason, would there be any issues from doing that?

 

Not that I could determine.

The actual filter locks onto the top 2" of the snorkel & locates in the lower section of the filter box to stay in place so its not part of the structure. The design limits the overall surface area of the filter that could be used as well.

On the left is the original design and the right is after the mod:

I believe that this approach has also been taken by Coxy & Clogz as part of the overall modifications to the air-box to increase airflow.

 

I trimmed mine over 12 months ago when I was doing a few other mods to the air box.
I'm not sure that Clogz has done this

 

I can't see how that is going to increase airflow - the bit you've cut off has a bigger cross-sectional area than the pipe it feeds into.

It was there for a purpose - maybe to ensure that air is pulled in over the full area of the filter, maybe to smooth airflow into the induction tract, maybe to tune the length of the induction tract for optimum performance. . .

 

I'm not sure my diagram did it the justice it needed Dave. The internal snorkel is in fact the same diameter as the inside edge of the air filter, so does restrict the airflow through the filter to 1/3rd of its overall surface area.

If its job was to help flow air, the person who designed it was clearly high.

 

Here is the refined airflow:

I am sure it did serve a purpose, and your right in your assertion about turbulence as that is the most likely use, but given you can replace any stock airbox with a straight intake cone, this mod is no different, except it keeps the intake out in the cool bit of the car.

 

Sometimes these odd designs are to cancel out resonance and noise. Neither of which I'm bothered about on mine - might do it the next time the undertray is off

 

I would be flabbergasted if this gives you any performance increase - It just won't. In fact, there's really no point changing anything inside the airbox whilst leaving the original entry ducting untouched... You know, the ducting that sucks fresh hot air from your engine bay...:lol:

:thumbs:

 

I'm not looking for a performance increase Clogz. It was primarily designed as a preventative measure to reduce the straw effect of the airbox given the qty of rain in the country at the minute. The fact it exposes over 2/3rds of the filter to direct airflow can only improve things though, if not in a measurable, significant way.

:thumbs:

 

I can see your point re - the likelyhood of water being sucked up via that original length inner tube , if the water got up to that level by getting in through the screwed plastic bottom plate . I'd rather attempt to find another place to draw in cold air that's not sited flush with the floor. If that's a non starter space wise then making a better seal when fitting the bottom plate would help keep water out when presented with road water deeper than estimated. NOT actually too difficult BUT at some point each year it's got to come off for a filter change , otherwise I'd use Sikaflex --- nothing would get in , even in flooded roads sealed with that stuff.
Possibly the orange sealant that I use for gearbox/diff instead of gaskets might do it --- my oil's never leaked a drop from the race car using that(need to check the receipt , forgotten what it was now)

 

Heh, nothing ventured nothing gained.
Years ago I had an Astra gte, 1.8 mk2.
Opel/Vauxhall had designed the airbox with a "torque trumpet" in it.
A 2" intrusion into the filtered side.

With this removed the engine gained 12lbft and 15bhp!
Sometimes ya jet gotta try these things!

 

Jeez, I never realised the 'snorkel' inside the air box extended that far down. Might have to look into doing this as a road I use going to and from work is known to flood and this may lessen my fear if I have no option but to drive through the flooded area.

Off topic but to do with this area, what exactly is the box in front of the drivers side suspension turret ? It has a pipe feed from just before the MAF sensor and a pipe going back into the inlet piping after the MAF.

 

Off topic but to do with this area, what exactly is the box in front of the drivers side suspension turret ? It has a pipe feed from just before the MAF sensor and a pipe going back into the inlet piping after the MAF.

I could be wrong, but talking to other forum members before we think it is a "Resonance chamber" designed to help quite down the intake noise. I plan on removing it and plugging the pipes that feed it to see what impact if any it has on the flow. Its most likely there to help control noise and turbulence in the air flow though.

I took the car out for a spin last night and it was no worse than before. In fact my a r s e dyno said it was stronger and more grunty, but that is obviously highly subjective...

 

Hi Guys, can anyone please tell me, how do I dismout that airbox, without taking off bumper and half of the engine? Is it screwed somehow? Mine is unfortunatelly broken and I need to replace it..
Thx

 

A few months ago changed filter to a bmc filter and found water sitting in bottom of air filter housing.
I cut off the tube as it sat very low in the filter box leaving a darker patch when air is drawn in.
Snorkel removed, car sounds a litlle gruntier under the bonnet other than that same as before but less chance of sucking up water.
Sealed lid with sealant before refitting.

Sent from my SM-G920F using Tapatalk

 

Is there any evidence that cone filters with a direct cold feed help make any power on the 2.4jtdm?

 

It looks to me as if the snorkel is there to make sure air is drawn evenly through the air filter.

Without it, you may find that part of the air filter gets dirtier faster than the rest, and because you are no longer using the whole length of the filter to flow all of the air you have effectively created a restriction.


Also as long as the intake to the airbox sits low you will get water into the engine no matter how far down the snorkel is.

Turbo cars create a very powerful suction on the intake.