Intake modification options

[rtha6551]

Hello

Sorry if this has been discussed in depth before but I'm still finding out the best ways to use the search function :/

I'm thinking of modifying the intake system on my HDi and not too sure of the best way to go about it? This is in preparation for stage 1 mapping in combination with a de-EGR, decat exhaust and fmic (just for engine health, I'm only 18 so I don't want 150bhp under my right shoe so stage 1 it is).

So far I've thought of three options

• Standard airbox/uprated panel filter
  
• Standard airbox/panel filter with holes drilled into grill to maximise airflow around the intake scoop. Seems fairly restricted as standard, placing it behind a solid plastic grill? :S
  
• Or is it possible to run a neoprene cold air feed/trumpet from the passenger side foglight to the standard airbox? I'm not sure what size the airbox inlet is or the size trumpet I'd need to fill the fog so if theres any adaptation needed it could get messy?
  

Ideally I want to keep this under £80 so a closed forced induction kit like a BMC CDA, PiperX Viper etc isn't really an option unless I can find someone selling one cheap second hand.

Anyones experiences or other methods they've used as part of their modified air intake system I'd love to hear and any problems you ran into?

Thanks

[cully]

for a limited budget stage 1
all i would do is
service car
good oil
std panel filter
oil filter
fuel filter
install stage 1 map
then enjoy the car

once you have time and maybe a bit of money
look at
removing the cat
replacing the back box
blanking the EGR valve

the car can breath very well at stg 1 levels with the std air box and filter

the forum has exellent resources in the guide section on the different tunes of the HDI

enjoy your car

[Poodle]

You might need to take a second look at everything you've been told about what you can do to improve your intake. Then wave goodbye and condemn it to history.

Without spending a lot of money there really is very little you can do to improve the standard intake system. Any oiled cotton filter will soon ruin your maf for a negligible difference in performance and most won't filter as well as a standard item. Drilling your airbox will just be letting hot air in from the engine bay, rather than from the cold air feed. The standard intake trumpet can flow plenty and is already designed with an element of ram air in mind, i doubt you'll be able to find anything on the market in your budget that can improve on it. Also, bearing in mind our climate, do you want to put your intake anywhere nearer the puddles..? Just a thought, lol.

You'll find most insurers will tell you take a hike the moment you mention a fmic, just so's you know. If i was you i'd just stick to a stage 1 map, egr and exhaust mods. Take a look at the project and guide sections for more info on tuning HDis, there's a hell of a lot of information around. For starters, there's more you can do to your exhaust than just decat, have a read around.

[Piggy]

watch Might Car Mods video on mythbusting cone filters/induction kits etc...

good watch but basically showed that standard airbox with decent panel filter gave best power!!

[C.A.R.]

Cone filter on a petrol = epic induction note, on a diesel this is masked and virtually impossible to hear, so there are virtually no benefits to having one on a HDi.

[rtha6551]

You might need to take a second look at everything you've been told about what you can do to improve your intake. Then wave goodbye and condemn it to history.

Without spending a lot of money there really is very little you can do to improve the standard intake system. Any oiled cotton filter will soon ruin your maf for a negligible difference in performance and most won't filter as well as a standard item. Drilling your airbox will just be letting hot air in from the engine bay, rather than from the cold air feed. The standard intake trumpet can flow plenty and is already designed with an element of ram air in mind, i doubt you'll be able to find anything on the market in your budget that can improve on it. Also, bearing in mind our climate, do you want to put your intake anywhere nearer the puddles..? Just a thought, lol.

Cheers I wasn't aware of this! I always thought an uprated panel filter would allow better airflow than the standard paper unit, so it's best to just get a new OEM one rather than a foam/cotton one? I did realise that in the fog light it would be low but would it actually suck water up off the floor without being submerged? :/

watch Might Car Mods video on mythbusting cone filters/induction kits etc...

good watch but basically showed that standard airbox with decent panel filter gave best power!!

I've seen that on YouTube before very interesting watch if its the one with the Skyline? Of course without removing the headlights and staying road legal then I'll have to keep the airbox in place, but not to worry as it's quite well designed as standard?

Cone filter on a petrol = epic induction note, on a diesel this is masked and virtually impossible to hear, so there are virtually no benefits to having one on a HDi.

Thanks mate but I was planning on keeping the standard airbox in any case Also the cone filter would most likely be susceptible to a lot of heat soak thereby reducing performance?

[Dum-Dum]

Pretty much agree with what poodle says apart from im not sure quite how quickly the K&N will kill a MAF sensor. if the filter is oiled right you shouldn't be taking oil in from the filter really.

For your budget my money would be on a K&N pannel filter unless you can stretch to a BMC CDA

[rtha6551]

Pretty much agree with what poodle says apart from im not sure quite how quickly the K&N will kill a MAF sensor. if the filter is oiled right you shouldn't be taking oil in from the filter really.

For your budget my money would be on a K&N pannel filter unless you can stretch to a BMC CDA

Apparently a lot come from the factory over-oiled so it might be best if I cleaned it out straight away then reoiled it to an appropriate level?

As for the BMC CDA, would this be an alright substitution?

http://www.ebay.co.uk/itm/Universal-Carb...1e64a770cc

Cheers

[lolsteve]

As mentioned until you get a little older and have some cash stay away from Fmic, putting it on mine when I was 21 with a couple of years ncb hiked up the insurance by ~£300

[Poodle]

There's that Arron fella who broke his car for parts recently, he went through 3 mafs in under two years with a K&N panel filter, kept it properly oiled etc, but still killed them.

That link looks ok, but it doesn't seem to include a filter and says it "forces air into the engine bay"... Quite why they want to force cold air into the 'bay rather than the engine itself is beyond me, which doesn't matter anyway because it's nonsense - it works exactly the same as your standard airbox. The only difference is size, weight and cost of decent replacement filters: decent standard filter - £8; decent aftermarket filter to similar flow and filtering specifications that can fit inside that tube - £... well i don't know and cba to find out, but you can be bet it's going to be more than £8 lol.

Up to you at the end of the day mate, but when it comes down to the bottom line - bang for buck there's a ton of other mods that'll give you a better return on your money than something like this.

[rtha6551]

There's that Arron fella who broke his car for parts recently, he went through 3 mafs in under two years with a K&N panel filter, kept it properly oiled etc, but still killed them.

That link looks ok, but it doesn't seem to include a filter and says it "forces air into the engine bay"... Quite why they want to force cold air into the 'bay rather than the engine itself is beyond me, which doesn't matter anyway because it's nonsense - it works exactly the same as your standard airbox. The only difference is size, weight and cost of decent replacement filters: decent standard filter - £8; decent aftermarket filter to similar flow and filtering specifications that can fit inside that tube - £... well i don't know and cba to find out, but you can be bet it's going to be more than £8 lol.

Up to you at the end of the day mate, but when it comes down to the bottom line - bang for buck there's a ton of other mods that'll give you a better return on your money than something like this.

Very good points made mate cheers, I'll definetely be sticking to just the stock airbox and filter then Definetely not worth blowing unnecessary money on replacing MAFs etc when I can just keep replacing the £8 one now and then lol, put the money towards something more useful.

As for the FMIC I'm quite surprised they put such a huge hike on it, seeing as many other cars from different manufacturers come with them as standard simply as a cooling system which many believe the HDi benefits from even without going as far as stage 2 :S Of course it probably is seen as a mainly performance upgrade and if they can use it make a bit of extra cash they will!

[Dum-Dum]

Those cheap ebay enclosed filters do an alright job, they certainly dont loose power but they do clog eventually and id only fit one if i could no longer fit the standard airbox because of FMIC pipes

As above 130ish bhp in a 306 is seriously quick for an 18 year old. My first car was 50 bhp

[Eeyore]

just give it a good service and use a standard paper filter. There is proof of lots of cominations of filters etc and the paper one comes out on top!

[lolsteve]

http://www.ebay.co.uk/itm/330807373105?s...1423.l2649

Even cheaper, but looks it too

[Poodle]

Tbf i'm actually quite impressed they can do real cf for that price, what's the betting only the outside layer is cf and the rest is grp...

My thoughts exactly with the intercooler. I'm 27 and admiral know about everything on my car, the lowering, the pump, the map, stripped out etc, and it's barely made a difference to the premium. But when I mentioned an intercooler and it was an immediate refusal - i asked them to confirm with a supervisor because it seemed so strange, but they were very definite. As you say, some HDis come with intercoolers as standard, so... Who knows, that's insurance for you i guess lol.