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Basically smoothing box is good,drilling box is really only for additional noise
Basically smoothing box is good,drilling box is really only for additional noise
There is no advantage at all of a drilled air box it's a waste of time and energy
It's serpost to make it sound better but u have a tdi like my self it won't really give any more noise
So there for I wouldn't bother
Now smoothing ur air box might give u better air flow but would be so minamul extra air I wouldn't bother unless really board one day lol.
Your best best is a green stuff replacement air filter or get something like a Jetex cone filter like I have see my rr below for pics.
Hope this all helps
It's serpost to make it sound better but u have a tdi like my self it won't really give any more noise
So there for I wouldn't bother
Now smoothing ur air box might give u better air flow but would be so minamul extra air I wouldn't bother unless really board one day lol.
Your best best is a green stuff replacement air filter or get something like a Jetex cone filter like I have see my rr below for pics.
Hope this all helps
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Would still be better with a GOOD filter in an airbox with an updated cold air intake than an open cone.
Open cone's will draw warm engine bay air,enclosed airbox wont,period.
Open cone's will draw warm engine bay air,enclosed airbox wont,period.
People with 20vT engines sometimes drill their airboxes to get more induction/dump valve noise. That's all it's good for and the downside is that you draw in hot air from the engine bay, leading to less oxygen in the inlet charge.
No advantage at all for TDI's. There's really very little to be gained by mucking about with the induction side in any case, other than noise. The standard air inlet is already coming from the front of the car, so you can't get it any colder. With the turbo already sucking in air to order, there's no benefit from making the inlet tract larger before the filter.
No advantage at all for TDI's. There's really very little to be gained by mucking about with the induction side in any case, other than noise. The standard air inlet is already coming from the front of the car, so you can't get it any colder. With the turbo already sucking in air to order, there's no benefit from making the inlet tract larger before the filter.
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had mine on a tdi 150 for about 3 weeks, too loud got a bottom airbox from scrappy will do tomorrow
you guys keep stating heat soak, I take it you don't have intercoolers then??, take a look at time attack cars which run open cone filters, there thrashed round a track all day where maximum BHP matters and they don't suffer from heat soak, even if you run the coldest of air feeds, the air still goes into the turbo which has the hot side right next to it with the exhaust manifold which is red hot!!, all the cold air you have supplied is going to get hot!!, that's where decent front mount intercoolers do there job of cooling the charged air after the heat it has made in the turbo before it reaches your cylinders, heat soak only really affects N/A engines where there is no additional cooling 
You're the only one to use the term heat soak.
Time attack is sprint by another name: short intense time trials. The benefits of deep breathing on a highly tuned engine can easily outweigh the restriction of even a short inlet pipe in those very specialised circumstances. These are far from standard cars.
For a roadgoing car, there are clear benefits to taking in clean air from the front grill.
Any forced induction mechanism will cause the inlet air temperature to rise: Boyles Law (or was that Watts pots never boil - no, that's Sellar and Yeatman). Intercoolers are required to improve the charge density. But if you start off with hot, dirty air, you'll get less benefit from your forced induction than you would with clean cold air, even after the intercooler has done its work. Unless you're running no filter and have a limitless supply of engines.
Time attack is sprint by another name: short intense time trials. The benefits of deep breathing on a highly tuned engine can easily outweigh the restriction of even a short inlet pipe in those very specialised circumstances. These are far from standard cars.
For a roadgoing car, there are clear benefits to taking in clean air from the front grill.
Any forced induction mechanism will cause the inlet air temperature to rise: Boyles Law (or was that Watts pots never boil - no, that's Sellar and Yeatman). Intercoolers are required to improve the charge density. But if you start off with hot, dirty air, you'll get less benefit from your forced induction than you would with clean cold air, even after the intercooler has done its work. Unless you're running no filter and have a limitless supply of engines.
yes ok no body used the term heat soak but in posts 4 and 5 they state drawing in hot air, I will admit I'm was wrong using the words heat soak (not many people admit there wrong now a days), you use the term hot dirty air, are you meaning hot dirty air as in less oxygen in the air or hot air with dirt particles in the air???, I use a Jetex open cone on my 20vt, after reading reviews that it was the best filtration and most flow on back to back bench flow tests, I know some mags hype products up to sell them, but for £42 off badger 5 I brought a Jetex cone, to try back to back dyno tests against my smoothed air box with cold air feed, the differences I noticed in the dyno plot was the mid range torque was increased which is handy for day to day driving and the mid-top end power was higher, I didn't lose any low end power or torque which I was expecting to be honest.
that's just my personal view on open cone filters in engine bays, everyone has there own idea we may not agree on them but each to there own, there's to much bitching on forums now a days which spoils it, I'm always interested to read other peoples views on topics as it may prove me wrong and I may learn something
that's just my personal view on open cone filters in engine bays, everyone has there own idea we may not agree on them but each to there own, there's to much bitching on forums now a days which spoils it, I'm always interested to read other peoples views on topics as it may prove me wrong and I may learn something
Ok the agrguee ment is starting again lol there are benefits from the standerd system pull in more cold air so there for the air is more dence before it hits the turbo so there for there is more particles of oxygen in each part of air.
Ok now an open cone filter does not bring in as much cold air as a standerd system even with extra cold air feeds. But still brings in quite cool air.
Where the cone filter becomes into its own Is the cone filter brings in a lot higher amounts of air so there for more air can be pulle into the engine so for each partial of air brought in is still less dence than the standerd system but there are a lot more particles of air so there for the denceity dont matter so much. Due to it brings in higher amounts of particles of oxygen.
Ok now an open cone filter does not bring in as much cold air as a standerd system even with extra cold air feeds. But still brings in quite cool air.
Where the cone filter becomes into its own Is the cone filter brings in a lot higher amounts of air so there for more air can be pulle into the engine so for each partial of air brought in is still less dence than the standerd system but there are a lot more particles of air so there for the denceity dont matter so much. Due to it brings in higher amounts of particles of oxygen.
Inside the engine compartment the air is hot from passage through the radiator and the air-conditioning condenser, plus some heat from the engine, and dirty because it's next to the engine. In fact, with modern concerns over emission control, there's not really much coming off the engine that isn't already ducted away elsewhere (crankcase emissions, fuel vapour and so on) so "dirty" is probably the wrong word to use, so you're right to point that out.
If you have the undertray on, then there shouldn't be any road dirt getting in to the engine compartment. But the whole compartment is designed to be a low pressure area (to enhance airflow through the radiator) so it's "dirty" airflow, you lose the ram effect. However, outside of competition cars, this is really not worth a lot.
I haven't seen any proper test data comparing the various induction modifications: most of what we see in forums is anecdotal, people's opinions, often influenced by the fact they've spent money on a modification and that the sound is different. I've seen some data that shows most filters have very little significant difference in flow restriction: enough to make a difference in competition (where you're at full power almost all the time, and a few HP can make the difference between winning and losing) but not significant for daily driving.
I suspect that the best benefits you can give your engine in terms of induction changes are taking the PCV through a catch can to a separate filter, removing it as a source of contaminated air into the inlet, and deleting EGR (for those of us that have it, which is all bar turbo-petrol engines, I think). These two emission control systems put more hot and dirty air into the inlet than even the worst inlet/filter system could ever be responsible for.
If you have the undertray on, then there shouldn't be any road dirt getting in to the engine compartment. But the whole compartment is designed to be a low pressure area (to enhance airflow through the radiator) so it's "dirty" airflow, you lose the ram effect. However, outside of competition cars, this is really not worth a lot.
I haven't seen any proper test data comparing the various induction modifications: most of what we see in forums is anecdotal, people's opinions, often influenced by the fact they've spent money on a modification and that the sound is different. I've seen some data that shows most filters have very little significant difference in flow restriction: enough to make a difference in competition (where you're at full power almost all the time, and a few HP can make the difference between winning and losing) but not significant for daily driving.
I suspect that the best benefits you can give your engine in terms of induction changes are taking the PCV through a catch can to a separate filter, removing it as a source of contaminated air into the inlet, and deleting EGR (for those of us that have it, which is all bar turbo-petrol engines, I think). These two emission control systems put more hot and dirty air into the inlet than even the worst inlet/filter system could ever be responsible for.
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You only gain some with smoothing the airbox, seen some logging on this or vmvortex forum and it gave a couple more g/s of air.
I've drilled my airbox, I have a cone filter in the original housing, due to openings in my carbon bonnet, else the cone filter would get wet during rainy days and washing sessions. It gives me more dump sound and hopefully more air (hotter or colder, I dont know).
Pics or it didnt happen
Powerfilter in airbox by AndyRamdin / ND-Photo.nl, on Flickr
Drilled Airbox top by AndyRamdin / ND-Photo.nl, on Flickr
Drilled Airbox back view by AndyRamdin / ND-Photo.nl, on Flickr
I've drilled my airbox, I have a cone filter in the original housing, due to openings in my carbon bonnet, else the cone filter would get wet during rainy days and washing sessions. It gives me more dump sound and hopefully more air (hotter or colder, I dont know).
Pics or it didnt happen
Powerfilter in airbox by AndyRamdin / ND-Photo.nl, on Flickr
Drilled Airbox top by AndyRamdin / ND-Photo.nl, on Flickr
Drilled Airbox back view by AndyRamdin / ND-Photo.nl, on Flickr
I agree with what your saying the only person I have know of to do any proper logs with a cone filter fitted is vroomtrish and from the logs I read the cone filter out preformed the standerd set up on a TDI engine
But his tdi car is far from low powerd so there for the logs he has done proves it's better Obama higher powed car not on a standerd or even stage one car.
I did do some tests before I fitted my jr cone filter.
Ie I put a thermometer side my air box then on the edge of my cone filter took it on a Run got the engine to full temp and read the temps at low speeds and also at high speeds 60 plus
At 60 plus I found the temp diffrance between cone and standerd was 0.6 degrees diffrance but at 60 and lower the temp diffrance was 1.8 degree diffrance with the standerd set up being the cooler one
So I then did some basic maff read outs with a snapon scanner once again at same speeds and foun the cone filter always had higher read outs at all speeds and rev ranges but not by massive amounts.
I worked out the diffrance between the temp and air flow working out that they are ruffly the same performce with the cone filter leading but that's only with my Cupra having a front mount giving it the advantage due to higher air flow.
I know my tests were not quite 100 percent perfect but I had to test things for my self due to people never having a proper answer
Sorry for the long write up
But his tdi car is far from low powerd so there for the logs he has done proves it's better Obama higher powed car not on a standerd or even stage one car.
I did do some tests before I fitted my jr cone filter.
Ie I put a thermometer side my air box then on the edge of my cone filter took it on a Run got the engine to full temp and read the temps at low speeds and also at high speeds 60 plus
At 60 plus I found the temp diffrance between cone and standerd was 0.6 degrees diffrance but at 60 and lower the temp diffrance was 1.8 degree diffrance with the standerd set up being the cooler one
So I then did some basic maff read outs with a snapon scanner once again at same speeds and foun the cone filter always had higher read outs at all speeds and rev ranges but not by massive amounts.
I worked out the diffrance between the temp and air flow working out that they are ruffly the same performce with the cone filter leading but that's only with my Cupra having a front mount giving it the advantage due to higher air flow.
I know my tests were not quite 100 percent perfect but I had to test things for my self due to people never having a proper answer
Sorry for the long write up
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I've run both now on my LC.
The Neuspeed open cone kit with heat shield provides a 3-4gs airflow increase on it's own over the smoothed / drilled airbox that I ran with a GREEN panel filter.
For that reason I use the Neuspeed kit.
cast88
Guest
cheers guys some mixed but helpful comments there. im still learning about diesel's tbh. i think ill just upgrade the filter for now and see how i go. i only want a bit of extra noise really coz im having it remapped soon. cheers
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