This is a little experiment that I done today and what I found.
First thing to note is my car is not standard (a generic stage 1 map with add on mods) so though its the case for my car, it may be different for others.
Pretty much within the first month of owning the car I put an enclosed air filter on it so I cannot remember how the standard air filter feels, runs etc...but I have read that the standard is just as good as aftermarket.
So anyway, my enclosed air filter has a cold air feed from the front of the car where the standard air infeed used to be, running straight into the air filter, so the filter only gets the air that comes through that pipe, the pipe is 2.5" alloy and silicone joiners, so provides a nice, smooth air flow. But then I kind of figured that I'm restricting the amount of air the engine is getting as it can only take what the pipe can provide, cold air is good, but alot of air is good, so I had one but not the other, so I purchased an open cone filter and done a kind of 'experiment', nothing on rolling road or any of that, just simple driving around town putting my foot down, casually driving etc...
On both 'tests' the small vacuum pipe is to atmosphere (got a filter from darkside developments on the way)
With the enclosed air filter it was very punchy, I'd hit ~1800RPM and get thrown in the seat, which I loved, but figured, more air, more grunt, harder throw? So I fitted the open cone filter in the exact same set up as the enclosed filter, same position in the engine bay, same cold air feed pipe, but this time it'd be sucking in air from the engine bay as well as from the feed pipe. I took it for a test drive and didn't notice any difference apart from the tone was slightly different but nothing serious, and the engine reved a bit 'free-er' (is that even a word? lol) so at the bottom of my road are traffic lights, they were red for about 40 seconds and on pull off, instantly the car felt heavy, bogged down and I had to rev more and hold the clutch a bit longer than usual, I assume this was due to heat soak, but I put it down to it's because I know something is different with the car so I'm almost 'looking' for something to behave differently, and I ignored it. Whilst driving at around 30mph and putting my foot down, it didnt hit me as hard as it used to with the enclosed air filter, it felt less aggressive and more progressive, I preffered that to the enclosed filter as it 'felt faster' even though it was a weaker punch it seemed to get through the revs quicker and pick up quicker (probably placebo effect but it's what I felt/thought was happening). Then whilst casual driving, at around 2000RPM it would seem to hesitate and judder slightly, though I have read this can sometimes be due to the vacuum pipe being fed to atmosphere but I never had this with the enclosed filter.
So I carried on this way for about 6-7 miles just testing it at different speeds, different throttle positions, accelerating etc...1 mile later I was home, removing it and putting the enclosed filter straight back on. After a long drive the enclosed filter is still cold and the alloy intake pipes even colder where as the open cone was hot. As much as I liked, what felt like, a nicer pick up of speed, I couldnt put up with the heat soak at the traffic lights, every time I stopped at traffic lights it was the same bogged down feeling as before, I hated the bogged down feeling as would anyone, when you've been driving with a carbon fibre enclosed filter you REALLY notice the heat soak, and the juddering at 1900-2000rpm, it just didn't feel right when driving it, it felt like a totally different car, now some may say if someone done it without me knowing the filter was changed I wouldnt have noticed, but I really would, I could not believe how different the car behaved, MAYBE it is the placebo effect, but I much prefer the enclosed and recommend if you're changing the air filter, get an enclosed filter with a cold air feed.
I have a heat shield on the way for the open cone so will try it again with that but I don't see it making much, if any difference, but, I'm open to trying it, it should arrive tuesday/wednesday so I will test it again and post my findings with that if anyone is interested..
First thing to note is my car is not standard (a generic stage 1 map with add on mods) so though its the case for my car, it may be different for others.
Pretty much within the first month of owning the car I put an enclosed air filter on it so I cannot remember how the standard air filter feels, runs etc...but I have read that the standard is just as good as aftermarket.
So anyway, my enclosed air filter has a cold air feed from the front of the car where the standard air infeed used to be, running straight into the air filter, so the filter only gets the air that comes through that pipe, the pipe is 2.5" alloy and silicone joiners, so provides a nice, smooth air flow. But then I kind of figured that I'm restricting the amount of air the engine is getting as it can only take what the pipe can provide, cold air is good, but alot of air is good, so I had one but not the other, so I purchased an open cone filter and done a kind of 'experiment', nothing on rolling road or any of that, just simple driving around town putting my foot down, casually driving etc...
On both 'tests' the small vacuum pipe is to atmosphere (got a filter from darkside developments on the way)
With the enclosed air filter it was very punchy, I'd hit ~1800RPM and get thrown in the seat, which I loved, but figured, more air, more grunt, harder throw? So I fitted the open cone filter in the exact same set up as the enclosed filter, same position in the engine bay, same cold air feed pipe, but this time it'd be sucking in air from the engine bay as well as from the feed pipe. I took it for a test drive and didn't notice any difference apart from the tone was slightly different but nothing serious, and the engine reved a bit 'free-er' (is that even a word? lol) so at the bottom of my road are traffic lights, they were red for about 40 seconds and on pull off, instantly the car felt heavy, bogged down and I had to rev more and hold the clutch a bit longer than usual, I assume this was due to heat soak, but I put it down to it's because I know something is different with the car so I'm almost 'looking' for something to behave differently, and I ignored it. Whilst driving at around 30mph and putting my foot down, it didnt hit me as hard as it used to with the enclosed air filter, it felt less aggressive and more progressive, I preffered that to the enclosed filter as it 'felt faster' even though it was a weaker punch it seemed to get through the revs quicker and pick up quicker (probably placebo effect but it's what I felt/thought was happening). Then whilst casual driving, at around 2000RPM it would seem to hesitate and judder slightly, though I have read this can sometimes be due to the vacuum pipe being fed to atmosphere but I never had this with the enclosed filter.
So I carried on this way for about 6-7 miles just testing it at different speeds, different throttle positions, accelerating etc...1 mile later I was home, removing it and putting the enclosed filter straight back on. After a long drive the enclosed filter is still cold and the alloy intake pipes even colder where as the open cone was hot. As much as I liked, what felt like, a nicer pick up of speed, I couldnt put up with the heat soak at the traffic lights, every time I stopped at traffic lights it was the same bogged down feeling as before, I hated the bogged down feeling as would anyone, when you've been driving with a carbon fibre enclosed filter you REALLY notice the heat soak, and the juddering at 1900-2000rpm, it just didn't feel right when driving it, it felt like a totally different car, now some may say if someone done it without me knowing the filter was changed I wouldnt have noticed, but I really would, I could not believe how different the car behaved, MAYBE it is the placebo effect, but I much prefer the enclosed and recommend if you're changing the air filter, get an enclosed filter with a cold air feed.
I have a heat shield on the way for the open cone so will try it again with that but I don't see it making much, if any difference, but, I'm open to trying it, it should arrive tuesday/wednesday so I will test it again and post my findings with that if anyone is interested..
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