seperate air filters for turbo and supercharger? gain?

[lucifer666]

Car is at tsr currently, spent the last couple of months doing some DIY mods. Through understanding what's happening under the bonnet I think this may be a good mod.

As We know, the air gets sucked in through the cold air feed in the induction kit. It's then either allowed through the turbo by the throttle just after the straight piece of silicone hose or if you look at the start of the oem plastic pipe its directed down towards the supercharger by a very thin pipe around half the size coming from the intake.

Started off by thinking about increasing the size of this pipe but ended up thinking about giving thE supercharger its own filter. There's loads of space with the oem battery removed. Was thinking of even putting the old oem air filter back on and using an upgraded cone filter inside. Think it will fit with the itg kit on too.

The beneift won't be low rpm just using supercharger or high rpm using turbo as they will be working on their own, its midrange from 2.0-3.5rpm where they both share the same air supply. Saying that it may give the supercharger a bit more air on its own because of the small pipe that leads into it.


What do We think?

 

[Big-Pete]

the ecu would **** itself surely?

 

[lucifer666]

Ecu would adapt. Supercharger will suck just as hard but like an intake kit it would be less restriction. So better response.

 

[Beazy]

The 'charger feeds the turbo, they're not separate. So probably not worth even considering trying to hack stuff up to fit a separate filter.

 

[Beazy]

 

[NetworkMan]

The engine, and the air filter, receive maximum airflow when the engine is producing maximum power, which is at high speed. Assuming the engine was not designed by an idiot, the air filter will be sized so that under these conditions it will be giving minimal resistance to that airflow.

There will therefore be little benefit in using more than one air filter at high engine speed and even less at lower speeds.

 

[WJs]

Assuming the engine was not designed by an idiot

Looking at the some of the issues the early twinchargers had, your assumption might be wrong.

 

[lucifer666]

The engine, and the air filter, receive maximum airflow when the engine is producing maximum power, which is at high speed. Assuming the engine was not designed by an idiot, the air filter will be sized so that under these conditions it will be giving minimal resistance to that airflow.

There will therefore be little benefit in using more than one air filter at high engine speed and even less at lower speeds.

Im talking about midrange power when the air supply is shared. Its down to mapping, should there be more headroom with air flow when the supercharger is at 100% and the turbo is trying to spool up, you could get the turbo to spool earlyer and more quickly, higher earlyer, especially if you use a hybrid if its at the limit of air supply.

I will ask tsr to look into this

 

[NetworkMan]

Please can you explain what you mean by:

"It's down to mapping?"

and

"Headroom with airflow?"

As an engineer, I find these expressions rather meaningless!

 

[lucifer666]

What i meant was if the super charger and turbo share the same air supply, then if your increasing the demand for air through mapping by trying to get the turbo to boost higher earlyer on while the supercharger is still active, then it will get to the stage that your limited by the rate of air you can get into the turbocharger whilst keeping supercharger at 100 percent.

If you had a supercharger intake, the pipe would be larger so less restriction, so would help response.

I have been talking to someone whose completley re designed this engine, running close to 500bhp, he has done the same.

 

[Nutkin]

the turbo and supercharger are not active at the same time.

 

[lucifer666]

the turbo and supercharger are not active at the same time.

during switchover they are, hence why boost under turbo only is 19psi (revo map), peak is something like 22psi a little lower down. theres a throttle that regulates the switch over feathering in the turbo.

 

[cuprastoffs]

I no nothing about these engines but the diagram up a few posts makes me think the charger feeds the turbo.
Making it a no go?

 

[Nutkin]

during switchover they are, hence why boost under turbo only is 19psi (revo map), peak is something like 22psi a little lower down. theres a throttle that regulates the switch over feathering in the turbo.

for like 100ms

 

[Jay1990]

I like that your thinking out of the box. But its not going to work like that IMO. They are not stand alone systems. The supercharger fills the gap for the turbo and the turbo takes over as the supercharger runs out of energy(for want of a better word)

They are active at the same time,But not in the sense that you mean. The turbo is always spinning, just doesnt make required boost at lower rpm.

 

[ibizaracebrake]

People look at these engines and try to apply the same modifications used on 2L GTi type but it is only a 1390cc and does not require massive air filter/intercooler/exhaust. There IS scope for removing restrictions in basic air flow to filter/intercooler and in exhaust ie flexipipe. Owners whos mods work are the most useful mods to copy.

 

[vRSy]

I agree. The reason that guy did it in his golf 1.4TSI is because hes running a GT30+ turbo aiming for 500Hp. Obviously that is going to require some substantial air flow.

With the stock or even the LO270 you wont need anything as extreme as this and the gains would be negligible.

Most people seem to think that the supercharger operates all the way until 3500rpm when in reality it doesnt. It operates until the turbo is on boost then disengages completely and when logged i've seen that the supercharger disengaging on mine as early as 2500rpm as the turbo is already on song and on boost. This is why pulley upgrades and supercharger upgrades are pointless.

So consider when driving how likely you are to be in the 2500-3000rpm power band when driving spiritedly? Not very often id imagine, and in reality its not wise to go WOT at those sort of revs in higher gears as its not healthy for the transmission and clutches as you expose them to the peak torque for a prolonged period. Its better for your transmission and ultimately performance to change down a cog or two, use the power instead and protect your transmission.

 

[CraigJack]

Slightly off topic here,

But those pics on a post above; I remember reading a PDF about the 1.4tsi, I'm I right in saying that the supercharger is covered with sound deadening? If so would I be a easy job to remove

 

[Nutkin]

Slightly off topic here,

But those pics on a post above; I remember reading a PDF about the 1.4tsi, I'm I right in saying that the supercharger is covered with sound deadening? If so would I be a easy job to remove

Yes it is and no it isn't but if you get it on a ramp maybe you will have a better shot , it's at the back/ bottom of the engine

 

[Paulyb92]

the ecu would **** itself surely?

lmaoooo! actually laughed out loud