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Open cone filters just suck in hot air from the engine bay and can reduce power (& increase noise).
A fully-enclosed cone filter with cold air feed would probably be best for power but probably expensive and space might be an issue.
A site I used to subscribe to (www.autospeed.com) often got good results (measured as a reduction in the pressure drop through the intake system) by running a larger-diameter cold air feed pipe into the existing airbox.
Changing the standard panel filter for an aftermarket one usually made little or no difference to the pressure drop in the intake system, provided the standard filter was not very dirty.
A fully-enclosed cone filter with cold air feed would probably be best for power but probably expensive and space might be an issue.
A site I used to subscribe to (www.autospeed.com) often got good results (measured as a reduction in the pressure drop through the intake system) by running a larger-diameter cold air feed pipe into the existing airbox.
Changing the standard panel filter for an aftermarket one usually made little or no difference to the pressure drop in the intake system, provided the standard filter was not very dirty.
This topic is about the most boring one that keeps coming up.
no matter wether you have a cone, panel or no filter at all, the temperature of the air is gonna be the same. Think about where the air goes before it gets to your Engine.
Through the TIP (that runs right past a 1000deg turbo), into that 1000deg turbo, then its cooled before entering the engine.
If you draw in air at 10deg, or air at 50deg, it'll make no real difference unless your intercooler isn;t up to the job
no matter wether you have a cone, panel or no filter at all, the temperature of the air is gonna be the same. Think about where the air goes before it gets to your Engine.
Through the TIP (that runs right past a 1000deg turbo), into that 1000deg turbo, then its cooled before entering the engine.
If you draw in air at 10deg, or air at 50deg, it'll make no real difference unless your intercooler isn;t up to the job
Not quite. The hot part of the turbo is the turbine, but the compressor compresses the air and runs considerably cooler (nowhere near the turbine operating temperature) - ever wonder why the two halves of a turbo are made of very different materials?
The air temperature after the compressor is maybe 100-150°C at most, with most of the heating generated by the compression process itself and not heat transfer from the turbo housing/impeller (residence time in the turbo is very short, after all) so the inlet air temperature does make a significant difference to the charge density before the intercooler. When the outside air temperature is, say, 10°C the underbonnet air could be 40-50°C or more...
There is also the additional issue of flow restriction. A larger-diameter intake into the standard airbox can reduce the pressure drop between the atmosphere and the interior of the airbox. The engine is not having to work as hard to suck air through the intake...
I'm well aware of how turbos work and the theory behind what your saying. But this is the real world, not the theoretical world, so I stand by what I say. You'll notice no performance gain/loss between paper panels/cotton panels/cones/enclosed cones or no filter.
Well, I certainly notice a difference in engine power and response when driving my Leon TDI on a cold winter day and a hot Summer's day. This was even more noticeable on my previous Focus TDCI.
Both cars were/are turbocharged and intercooled and both had air ducting leading directly from outside the engine bay to the air filter, so the only variable was external air temperature.
I fitted a larger diameter duct into the Focus' airbox, a K&N panel filter and removed the resonator (diameter restriction) from the turbo inlet and, apart from extra noise, could be persuaded that perhaps I was imagining any performance difference from doing so, but the effect of outside temperature was and is certainly not a figment of my imagination.
So, I cannot agree that there would be no power difference using a cone filter, drawing hot air in from the engine bay, and the original airbox, drawing cold air from outside the engine bay.
Both cars were/are turbocharged and intercooled and both had air ducting leading directly from outside the engine bay to the air filter, so the only variable was external air temperature.
I fitted a larger diameter duct into the Focus' airbox, a K&N panel filter and removed the resonator (diameter restriction) from the turbo inlet and, apart from extra noise, could be persuaded that perhaps I was imagining any performance difference from doing so, but the effect of outside temperature was and is certainly not a figment of my imagination.
So, I cannot agree that there would be no power difference using a cone filter, drawing hot air in from the engine bay, and the original airbox, drawing cold air from outside the engine bay.
Of course, but that doesn't change the fact that if the air entering the turbo is 20-30°C cooler (through using a cold air feed/scoop as opposed to an open cone filter), then although it will gain a certain amount of heat during compression, which is largely adiabatic (i.e: fast enough that significant heat loss to the environment does not occur), it will also exit the turbo compressor at a lower temperature before it reaches the intercooler...
Plus, and I'm guessing now, I assume the effectiveness of the intercooler depends on the temperature differential between the air inside it and the air outside. If the outside air temperature drops by say X°C and the intake air temperature is cooler by the same amount(relfecting the former), then I wonder if the IC does in fact cool the charge more in lower ambient temperatures?
Plus, and I'm guessing now, I assume the effectiveness of the intercooler depends on the temperature differential between the air inside it and the air outside. If the outside air temperature drops by say X°C and the intake air temperature is cooler by the same amount(relfecting the former), then I wonder if the IC does in fact cool the charge more in lower ambient temperatures?
iwonagain
Guest
Altitude doesn't change much - pretty close to the sea here
Seriously, though, does anyone on here know if intercooler performance improves as outside temperature drops?
If the outside air entering the induction system is, say, X°C colder on a given day then is this replicated by the air temperature leaving the turbo and, if so, then surely the difference in air temperature inside and outside the intercooler is the same and so there's no more cooling going on?
Any automotive engineers on here?
Seriously, though, does anyone on here know if intercooler performance improves as outside temperature drops?
If the outside air entering the induction system is, say, X°C colder on a given day then is this replicated by the air temperature leaving the turbo and, if so, then surely the difference in air temperature inside and outside the intercooler is the same and so there's no more cooling going on?
Any automotive engineers on here?
FR06BlackMagic
Guest
maybe im just a geek but this is interesting as far as im concerned - partly because i have no money but want the best out of my little FR130tdi - was thinking about an induction kit for noise purposes but thought that potentially thered be some performance gains. So (please excuse my ignormace) but cones are louder than performance filters but are performance filters louder than stock? And Ive heard a lot of people say that induction kits need to be fed with cold air to actually increase performance but that gains were only ever small?
opinions welcomed - plus more cheap mods if you guys can reccomend some
opinions welcomed - plus more cheap mods if you guys can reccomend some
in my experience, I couldnt hear any difference really, like you get on a petrol. Your best sticking to a better filter element with a ibiza cupra intake snorkle. Do a search on here for that.
Other cheap mods would be to fit a egr blanking plate or go the whole hog and do a egr delete. This may not give more power over stock levels, but you will regain bhp once its cleaned out.
Other cheap mods would be to fit a egr blanking plate or go the whole hog and do a egr delete. This may not give more power over stock levels, but you will regain bhp once its cleaned out.
A cone filter, drawing in hot air from under the bonnet, would be a retrograde step for power, but would make more noise.
A cone filter kit with cold air feed would be better, but it's unusual to find one where the cone is completely fed with cold air only.
Most likely the best improvement would come from de-restricting the standard airbox, usually by fitting a larger cold air feed duct to it, either the PD160 intake snorkel (pricy for what it is) or else a larger than standard diameter home-made intake pipe (englarging the hole in the airbox to accept this). Something like this:
http://www.auto-performance.co.uk/index.php?cPath=160
Best to fit a bellmouth to the inlet end to smooth the airflow.
There's usually little or no benefit to fitting an aftermarket panel filter in the standard airbox, and some cause MAF problems due to the oil on the filter.
A cone filter kit with cold air feed would be better, but it's unusual to find one where the cone is completely fed with cold air only.
Most likely the best improvement would come from de-restricting the standard airbox, usually by fitting a larger cold air feed duct to it, either the PD160 intake snorkel (pricy for what it is) or else a larger than standard diameter home-made intake pipe (englarging the hole in the airbox to accept this). Something like this:
http://www.auto-performance.co.uk/index.php?cPath=160
Best to fit a bellmouth to the inlet end to smooth the airflow.
There's usually little or no benefit to fitting an aftermarket panel filter in the standard airbox, and some cause MAF problems due to the oil on the filter.
How many of the above have you tried? My cone filter under the bonnet doesnt lose me any power.
In fact anyone I know of running a TDi with big power, has a cone filter. Thats not to say the airbox can't cope, but using a cone certainly doesn;t lose you any power.
Tried the open cone on my old Rover years ago. Made a lot of noise but that was about it.
Tried an open cone on a Mazda, but this time with an extension pipe to put it just behind the radiator (still not ideal due to warm air off the rad). No real improvement so reverted to a larger-diameter air duct into the standard airbox, with an inlet just ahead of the radiator in a high-pressure area. That helped.
Tried the drop-in K&N filter on my old Focus diesel, but didn't notice any improvements over the standard filter.
The guy at Autospeed (www.autospeed.com) has done a lot of testing of different intake systems using a manometer to measure pressure drops in different parts of the system, on many different cars. He generally found that drop-in filter elements made little or no difference compared to standard paper filters, and that most of the pressure drop in the systems could be reduced by changing the air inlet to the airbox and/or the outlet from the box to the engine.
On my old pd150 hybrid I used a panel filter kn, a bmc cda, and a jetex cone. The cone gave me the best power and the best throttle response. Between that and the intake sits a bloody great big intercooler. You cant compare against different makes of cars as that's not very scientific. Ford tdci intercoolers are frankly so small it's funny.
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