Shall I jump on the slope?

[pudding]

Actually you can change the dynamics of the engine through cam timing changes etc. to the point where the difference is negligible

So how would a graph provide a fair comparison? If you only care about sub 2500rpm then why not buy a diesel or a naturally aspirated engine!? Why not a comparison of the full rpm range to show where there are losses and where there are gains in order to judge whether it is 'worth having'........ and would it be back to back or with mapping changes to take full advantage?

If intakes were a waste of money then why does everybody fit one? Anyone got a high power K03 or K04 on the standard airbox?

People seem to forget that there is always a trade off when modifying or changing parts. Removing a restriction will cause the air flow to slow which will hinder low end performance slightly (i.e. off boost driving), but provide gains when 'on boost' which should outweigh any negatives. I have a very free flowing intake and I have absolutely no noticeable loss of off boost performance, and the turbo is almost always there, spooling up and aiding performance, full boost is achieved well below 3k rpm...... so I'm yet to see a drawback... but then my MAF scaling is near perfect, idle trims within 1% and multiplicative hovering between -1 and -5% (due to meth - disable this and its within 2 or 3%)

That's the other thing people are always forgetting is MAF scaling and the difference it makes when swapping out to an intake without having the MAF scaling adjusted to suit. When I ran the RamAir MAF pipe on mine the car felt lethargic and registered peak MAF readings 30g/s lower than my current intake

Just winds me up when people slate or discourage others from using intakes when there are gains to be had, because somebody somewhere had a bad experience with one, or expects the car to respond just as well and there be no trade-off at all.... .If there was no trade-off then the manufacturers would fit a much more free-flowing induction system from factory..... but they don't..... Their priority is efficiency, fuel economy, minimum NVH etc. etc... not ultimate peak performance under WOT

VVT only has a marginal affect on the tune.  This is no VTEC, it merely shifts the overlap, not duration or lift.

That's a pretty narrow minded view.  I'm not interested in diesel.  I know I'm in the minority (I usually am) but I like to improve the car with making zero sacrifices.  Fitting an intake that blunts the off boost responsiveness is a sacrifice.  I know intakes can aid more hp at the top end, but that's not where I drive my car. 

Interesting point about naturally aspirated.  Anything you can do to improve a n'asp engine also works for boost.  How many aftermarket intakes for n'asp engines do you know of that fatten up the bottom end?  No, I can't think of many either.  We've all been there in the past fitting K&N cones to n'asp engines and regretting it.

From what I've read on here, a lot of people fit intakes for the noise.  That's fair enough if they like it.  Yes Shouduci's ED30 makes 330hp with the factory air box.  Seems like a win-win situation for me and proof that the factory airbox is not as restrictive as some people would have us believe.

Well you have a K03, some of us have K04s, where a change in induction tuning is a lot more noticeable off boost.  My bad, I should perhaps state that before getting into it.  If you're happy with your setup, good for you.  No one is stating rights and wrongs.

Yes the MAF scaling.  The tuning around the factory airbox's elliptical MAF housing is very sensitive.  I'm sure quite a few folk have come a cropper with that after chucking the factory airbox into the wheelie bin.

What's your beef with some people having a difference of opinion?  Who is slating & discouraging?  It's a forum i.e. exchange of information, ideas and conversation.  All I did was ask for a torque plot below 2500rpm and you've taken it personally.   OEMs do fit good intakes.  Why else do people feel a blunted bottom end when they bin it?  There's always people who say "no my 3" full system doesn't drone", "no my poly engine mounts don't increase vibration", "no my after market intake doesn't blunt off boost performance at all" but I don't buy it.  Ying and yang.  There is always a trade off, just 90% of people downplay them to justify the cost of the parts.

[Dan_FR]

VVT only has a marginal affect on the tune.  This is no VTEC, it merely shifts the overlap, not duration or lift.
VVT can aid turbo spool up by some 500rpm depending on application, will more than make up for the loss from an intake

That's a pretty narrow minded view.  I'm not interested in diesel.  I know I'm in the minority (I usually am) but I like to improve the car with making zero sacrifices.  Fitting an intake that blunts the off boost responsiveness is a sacrifice.  I know intakes can aid more hp at the top end, but that's not where I drive my car. 
This may also be narrow minded, but would you not have been better in a K03 if you are worried about sub 2500rpm performance? Not all intakes 'blunt off' boost if the intake is well designed and the MAF is scaled correctly. It will always have some impact. If you are not interested in HP then an intake is not for you

Interesting point about naturally aspirated.  Anything you can do to improve a n'asp engine also works for boost.  How many aftermarket intakes for n'asp engines do you know of that fatten up the bottom end?  No, I can't think of many either.  We've all been there in the past fitting K&N cones to n'asp engines and regretting it.
Not talking about tuning an N/A or fitting an intake, I'm talking about responsiveness low down i.e. no waiting for the turbocharger. I won't even go in to the difference between fitting a K&N filter vs. a propely designed intake

From what I've read on here, a lot of people fit intakes for the noise.  That's fair enough if they like it.  Yes Shouduci's ED30 makes 330hp with the factory air box.  Seems like a win-win situation for me and proof that the factory airbox is not as restrictive as some people would have us believe.
I said high power...... 330hp is not high power on a K04 when some have hit north of 400.... Show me a K03 car making north of 280hp on the factory airbox, when 295-300hp has been achieved in the past on high flowing setups.....

Well you have a K03, some of us have K04s, where a change in induction tuning is a lot more noticeable off boost.  My bad, I should perhaps state that before getting into it.  If you're happy with your setup, good for you.  No one is stating rights and wrongs.

Last time I checked this was about tuning a K03....... What software and intakes have you tried to draw these seemingly concrete conclusions out of curiousity?

Yes the MAF scaling.  The tuning around the factory airbox's elliptical MAF housing is very sensitive.  I'm sure quite a few folk have come a cropper with that after chucking the factory airbox into the wheelie bin.

Exactly my point. People buy a terrible intake with dreadful MAF scaling, or have other issues with the car itself and then claim that all intakes lose engine response and off boost drivability....

What's your beef with some people having a difference of opinion?  Who is slating & discouraging?  It's a forum i.e. exchange of information, ideas and conversation.  All I did was ask for a torque plot below 2500rpm and you've taken it personally.   OEMs do fit good intakes.  Why else do people feel a blunted bottom end when they bin it?  There's always people who say "no my 3" full system doesn't drone", "no my poly engine mounts don't increase vibration", "no my after market intake doesn't blunt off boost performance at all" but I don't buy it.  Ying and yang.  There is always a trade off, just 90% of people downplay them to justify the cost of the parts.
My beef is when people form an opinion, without providing all of the facts or the other side of the argument, and give it to those people who are none the wiser, who then accept this as a proven fact, when it simply isn't.
You asked for a torque plot of a very small rpm range to prove that there are some minor losses but without presenting the whole picture in terms of what you gain across the rest of the rev range. You provide a blanket 'intakes lose you drivability' statement when in reality a decent intake with decent software result in marginal losses to the point where you would barely notice... But the key thing here is the intake, the software and the general health of the car....

I agree on the latter comments about difference of opinion on noise, vibration etc. as well as some cars genuinely having less vibration or noise for a variety of reasons, but there is a much bigger picture when it comes to intakes and this wasn't presented to the OP - just a very negative one-sided story that I have seen banded about a lot on this forum and usually when I do not have the time or energy to bother writing a counter argument

[flashp]

@driver rider - 3. May I ask why you recommend these tyres.  What about the michelin pilot sport cup 2? Or the Pirelli high performance tyres?  I ask looking for guidance and not because I know whats best.

The Cup 2's are brilliant tyres by all accounts. They come with 5mm of tread I believe, not sure how they wear on the road but they are superb on track according to all reviews. I wanted an 'everyday' tyre that could manage the odd track day. Michelin developed the PSS on track as well as road and they are intended to be able to cope with my typical usage. Cup 2's may have been overkill for me.

I have no experience of Pirelli tyres at this level.

As for intakes and their effect at this tuning level my opinion was based on experience. Torque band shifting further up the rev range and boost being slightly delayed amount to the same thing since the turbo is largely responsible for the torque delivered. The difference is perceptible. Around town and at regular speeds I preferred the characteristic of the stage 1 Revo map for which I ran a standard intake. By this you can infer that a stage 2 tune is better when you are in the top half or thereabouts of the rev range but since you don't want to spend large sums of money the stage 1 is by far the biggest bang for your buck and demands far less hardware to be at it's best.

Interestingly KO3 cars don't suffer with compressor surge which becomes evident in stage 2 KO4 tunes. It has to do with the volume of the compressor housing and impeller shape/profile. Beach Buggy Turbo's https://www.facebook.com/beach.buggy.10/ have a kit containing revised parts to eliminate this. Just for interest 

I would be interested to have my standard intake put back on while keeping my stage 2 tune. I'd like to try it out of curiosity but I can't justify the labour costs in getting it done and having the map trimmed to suit. I know there are some who have done just this and don't regret it.

I'm not going to get into who's right and wrong, information is what you asked for and so much of this is subjective.

[pudding]

My beef is when people form an opinion, without providing all of the facts or the other side of the argument, and give it to those people who are none the wiser, who then accept this as a proven fact, when it simply isn't.
You asked for a torque plot of a very small rpm range to prove that there are some minor losses but without presenting the whole picture in terms of what you gain across the rest of the rev range. You provide a blanket 'intakes lose you drivability' statement when in reality a decent intake with decent software result in marginal losses to the point where you would barely notice... But the key thing here is the intake, the software and the general health of the car....

I agree on the latter comments about difference of opinion on noise, vibration etc. as well as some cars genuinely having less vibration or noise for a variety of reasons, but there is a much bigger picture when it comes to intakes and this wasn't presented to the OP - just a very negative one-sided story that I have seen banded about a lot on this forum and usually when I do not have the time or energy to bother writing a counter argument

I forgot about this!

Can't be bothered to go through all of those points again - you have your opinions, I've got mine - but I do take issue with your attitude towards me as being a heretic and naysayer just because I was interested in an area of the dyno plot most others aren't, and have a different opinion to you.   Where exactly have I categorically stated - as a fact - that all aftermarket intakes will rob power everywhere in the rev range, because that is what you're implying?   I agreed with you that they can free off power in upper rev ranges.  That isn't in question, it's basic physics.

You may only be interested in what occurs 'above the curve', but below it is another area some folk are interested in, believe it or not.  And we have to take your word for it that intakes don't affect things down below.  Where are YOUR facts to back that up?

I repeat my original question, which intake (for both K03 and K04 applications) matches or is *better* than standard below 2500rpm.  If there is one, I will buy it. It seems odd to spend money tweaking the intake VVT to get the torque back to where it was before fitting an intake, no?  It reminds me of people fitting the HPA TFSI intake and losing 50lbft torque off boost.  Yes ladies and gentlemen, VW fitted runner flaps and used narrow intake manifold bores for a reason - torque!

It may only be 20lbft down below 2500rpm, but it's a heck of a lot more noticeable than losing 20lbft at 3500rpm.   It may not bother you, you it does other people.

[Dan_FR]

Me too!

By the way it's not an issue with you personally, perhaps my attitude did not come across as it should when typing a reply on an online forum, so for that I apologise..... Just trying to get the whole picture across to the OP, not just focus on one small negative aspect which you have found on your K04 engine'd car with one (or a couple of different aftermarket intakes?), but for me is very minor and unnoticeable (if even present, not had a factory airbox in over 2 years)... But then again I do not have the lower compression engine or the K04 turbo so that could well explain it.... but this topic was started to discuss the K03 which is why I piped up.

Just to clarify, the sub 2500rpm performance loss you speak of, is this at W.O.T. or are you talking about normal driving, light/mixed loads and cruise below this rpm?

It seems odd to spend money tweaking the intake VVT to get the torque back to where it was before fitting an intake, no

This bit did make me chuckle though as I don't find it odd at all. Fitting an intake and then having the car tuned to take full advantage of the intake & other hardware, utilising the VVT and the gains it can bring is not odd at all, and can minimise or remove any loss you feel sub 2500rpm whilst bringing the gains that an intake does in the upper RPM

Without spending more money on software, I don't think you will find anything more responsive than the factory airbox, factory MAF scaling in the software.... The runner flaps are negligible as they are only designed to operate when there is no engine load between 1000 and 5000rpm when the engine is making less than 15lbft of torque:

Taken from the TFSI design PDF:

The tumble flaps are actuated:
• To improve cold engine idling
• To improve charge efficiency at start-up
• In overrun mode

This is why people deleting the runner flaps only notice a drawback at idle and cold start, and then get a few more pops/burbles on the overrun, but no other issues

[driver rider]

Hi Gents,

thank you for all your helpful replies and lively debate.  It makes for a good read.

So I have decided that I'll go for brakes, springs and arb's.  Then I will go for a stage one.  I feel better handling will help me out on the track more than extra power would.  It will also help me enjoy the car on good b roads more!

I will keep an eye out for group buys and part sales.  Maybe I will be able to get it cheaper and get everything on my wish list! 

I will also look into walk kit as well.  Most of my driving is low speed.  So perhaps an intake is not good for me. 

I would love an exhaust and also an intercooler but I don't have funds and need to keep saving money for a place.

please keep the info coming!

[AJP]

Hi Gents,

thank you for all your helpful replies and lively debate.  It makes for a good read.

So I have decided that I'll go for brakes, springs and arb's.  Then I will go for a stage one.  I feel better handling will help me out on the track more than extra power would.  It will also help me enjoy the car on good b roads more!

I will keep an eye out for group buys and part sales.  Maybe I will be able to get it cheaper and get everything on my wish list! 

I will also look into walk kit as well.  Most of my driving is low speed.  So perhaps an intake is not good for me. 

I would love an exhaust and also an intercooler but I don't have funds and need to keep saving money for a place.

please keep the info coming!

That's a sensible route to take. It's all too tempting to up the power first and neglect braking and handling.

I'd have a look at these ARBs if I were you. Good value by the sound of it, and H&R make some of the best bits out there:

http://www.mk5golfgti.co.uk/forum/index.php?topic=106891.msg1036332.msg#1036332

I'd have snapped them up myself but I need to budget for other stuff at the minute unfortunately!