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Hi Guys,

Have read a lot about choices for different types of induction kits & opinions on which models are best. However, what experiences of routing cold air feeds do you have?? I have a BMC kit under the bonnet of my 160 & have been playing around (without much success!) with the positioning of the cold air feed pipe. The bore of the intake pipe for one causes problems, fitted fog lights another. Is it a case of a front bumper off job to route it properly?? Any experiences with this thread would be greatly appreciated.


Cheers

Rob.
 

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Got mine routed out the bottom of the engine bay....... cut away a small square of the undertray to get it to run right. Also lagged the intake pipe to stop it burning thru on the zorst as it was very close. Had no problems so far and getting sufficient air flow, so im sticking with this.

Did have one of the fog lights out to see, but looked terrible so went back to the first option........plus its easy to remove if needs be.
 

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WOT U WONA DO IS HAV 1 END OF THE COLD AIR PIPE CLOSE 2 THE FILTER AND THEN EXTEND THE PIPE DOWN PAST THE FRONT OF THE ENGINE AND BEND IT 2WARDS THE FRONT OF THE CAR. SECURE THE TOP OF THE PIPE WITH A ZIP TIE AND THE BOTTEM AGAIN WITH A ZIP TIE 2 THE FRONT WHEEL STRUT IN THE CENTRE. THERE IS ROOM 4 2 COLD AIR FEEDS
 

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i have a viper now but it is only connected to the existing air intake but i definatley want to bring the feed in from the front grill - does any one know what the box is below the battery that has a pipe that feeds up into the intake and how to get the smaller box of the front which is fitted below the light cluster without taking the front of the car of

thanks

:xmas:
 
G

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You have to remove the front of the car if you want to remove the standard intake. The 'box' you are on about is a combined plenium chamber/water trap. Without these items and by routing the cold air pipe directly into the airflow then you run the risk of sucking up not only air but all the road muck/bugs/water etc and clogging your filter in double quick time. Routing the pipe anywhere close to the engine/exhaust/radiator will also defeat the whole idea of having a cold air pipe as the pipe will heat up when stationsary and heat the air inside, once again bringing on the dreaded 'heatsoak'. Dont you think that is why there are so few cars on the road (if any) that have a direct feed ram air pipe as standard. Even those with big intakes like Scoobies and such have some form of plenium chamber and most have the intake sited well above the road to lessen the amount of rubbish getting sucked into the pipe. No matter how much air you ram into the pipe and you could have a cold air feed the diameter of a dustbin but the engine will only use what it needs and the rest will just stagnate. It is like the analagy I posted on a previous thread. If you have a door that will only allow 3 people through at a time because of its size then it dosent matter how many people you have trying to push through, even if there were 3,000 in the room, they will only go through 3 at a time. The restriction you have is the filter and the diameter of the throttle body. Any pipe bigger than this will not make the slightest bit of difference as that is the narrowest part and therefore the biggest restriction.

Unless the pipe is in dead air (as it is with the standard intake) any deviation from perpendicular to the airflow will cause a venturi effect and will suck air instead of blowing. Plus having it in dead air will prevent the ingress of foreign objects and lessen the amount of water. Stationary there is no ram air effect anyway so at the green light F1, there is no difference between using the standard air intake or a ram air and in fact if the ram air pipe is routed anywhere near the engine they you will get heatsoak and suffer hesitation and power loss. Ram air on the move is little or no effect as already the stated the engine will only use as much air as it requires. the only way to get more is to use a forced indcuction system and this is not what ram air does. A forced induction system is either a Turbo or a supercharger.

There are a lot of other considerations as well and a plenium chamber will also act as an air resevoir so that when you press your foot to the floor and you get the massive depression in the intake, the lenium chamber is able to supply and dissipate this depression allowing the stagnant airflow through the pipe to catch up and gain momentum.

So as you can imagine there is a lot more sience and physics into induction systems than just sticking a piep into the air and hoping for the best. Manufactureres have spent millions developing systems that give the best balance of efficiency against cost. There is room for improvement as demonstrated by the methods that racing temas use (How many of them use Vipers etc). Most dont use a closed induction system at all but rely on huge open fitlers that offer minimun airflow resistance and a decent ram air cold feed to supply as much air as possible.
 
G

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Personally if money was no object I would probably opt for the carbon fibre X-power induction system. I am pretty certain this is made under licence and rebadged by Maxtor or ITG. It replaces but uses the same air intake as the stanadard system. I am currently myself using a Diavolo carbon fibre plenium chamber fed from the standard air intake to avoid heatsoak and foreign object/water ingestion. Prior to this I had an Apiro Aiero on which looked ace, sounded great but suffered with heatsoak and hot air ingestion when trying to pull away from a standstill. (see the results below)

IMHO then you fit what you are happiest with. I beleive that my set up is little or no better than running the standard set up. To get a good idea then have a look at the most recent TotalMG magazine. There is a shoot-out there on a rolling road and makes some interesting reading. Just on the 105's, here is a short breakdown of results.

Standard Induction with x-power back box = 75BHP @ 6000
Standard induction kit only. 74 BHP @ 6000
Apiro open filter and powerflow back box 73BHP @ 6000
K&N Open filter 76BHP @6000
Pipercross Open 70BHP @ 6500
Full x-power exhaust system, X-power induction kit, 52mm TB 80BHP @6000
Apiro Ultima open 67 @ 6500

Some interesting results and considering that a standard 105 ZR was producing and indicated 74BHP at the wheels and beat the majority of the open filters proves that side of things.
The addition of an x-power back box gave 1HP increase
The biggest increase was a full x-power exhaust, induction and bigger TB. This proves the point about getting better and bigger flow into the engine coupled with a decent exhaust to help with the breathing. Not certain of the cost but I think the x-power induction kit alone is a couple of hundred and at least that for a full x-power exhaust. 52mmTBs are not cheap so a conservative £500 -600 + for 6BHP at the wheels. Not bad really consideringing REVVED up paid £1000 for 10BHP.

So intake mods alone dont make for much of an improvement alone but if done wrongly can cause quite a considerable drop in performance :xmas:
 

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the problem is that you dont know how cold the air is you are getting in the intake or wether it is in a dead air area at least if you have the feed getting air forced in from the front of the car you know there is no vacuum effect and it is very cold air - you could still connect the plenium chamber for the initial burst but i thought that is why there is a big air feed tube so a lot of air is already sitting in the tube.

although i want to know about the mechanics of getting the feed from the front grill (preferably the top grill to cut down on the rubbish and water being sucked up)) round the rad and to the filter - maybe the rad can be dropped back to allow more room

i have thought about using right angled brake air ducts or getting a stainless tube bent into shape

has anyone done it
 

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I'm getting a powerflow fitted as soon as MMV in Stirling can fit me in and combining that with an enclosed induction kit (apiro diavolo) hopefully better performance, so I'm not just going halfway house. So methinks I might get the best of both worlds.
 
G

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The option I was looking at once was to get a NACA duct fitted to the bonnet and have a feed from that directly into the plenium chamber.

As long as the intake for the air feed is outside of the engine bay then even in dead air, the ambient temperature will be the same as that of a ram air.

Unless there is some way of fitting a ram air system without routing it close to the engine then you will be defeating the point as the pipe will heat up by conduction/convection/radiation from the various and numerous heatsources. The air flowing through will have some cooling effect but only by transferring the heat from the pipe into the air flowing through the pipe (heatsoak again). Stationary, this flow is reduced and so the heatsoak is greatly increased, so the time you need the most acceleration, ie from a standstill is when you are going to have the greatest heatsoak problems

A big air tube could negate the need for a plenium chamber by supplying excess air to the engines needs, but then we are into Bernoulis laws where for a velocity increase you will get a pressure decrease (reason why a ping pong ball stays in a moving column of air such as from a vacuum cleaner). By decreasing the velocity you can increase the pressure, which is exactly what a plenium chamber does and also acts as an air resevoir to help with the sudden surges and demands of air for large throttle movements. A universal pipe diameter, regardless of size will not have these changes in flow/pressure or be able to react hence you will get surges and even reverse flow without a plenium chamber of large enough volume. It is these sudden changes of airflow that can cause a jet engine to surge and stall and why they are resticted as to how fast they can accelrate and decellerate. A jet engine is in essence a 4 cycle engine just like your car. They both have an induction cycle, compression cycle, igniton/power cycle and then an exhaust cycle (suck, Squeeze, bang, Blow). Sorry if this is a little heavy, but there really is a lot more to it than can meet the eye if you really dig.

There is also the matter of filter material which can also affect airflow as well. Competiton/race engines may not even have any but then again most are stripped and rebuilt after each event.
 

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thanks light sabre - so the plenium chamber stays

wonder if i can ease the radiator back slightly to make more room though the problem seems to be the pipes down the side of the rad dont leave much of a gap to bring the tube through - could the feed be brought through in several (or a couple) smaller tubes and then joined together or would it create to much air turbulance as it feeds in the filter
 
G

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That sounds like a great idea and air turbulence in engines can be a good thing as it can aid atomisation and fuel/air mix. That is the theory behind those funny little economax valves that some people fit (and that makes your car sound like Donald Duck).
 

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hmmmm...

this is quite helpfull, as I too had the same problem with heatsoak and no room for any cold air feeds. At the moment I've just got the lower half of the oe airbox under an open piperx cone, and built a little metal heatshield between the engine and filter then bending over the top of the filter. After a 'spirited' drive there was a noticeable difference in temp between the two sides, so I think its definatly worth doing something. Don't know if I want to take my bumper off though ! By the way, you sound quite knowledgeable on your fluid mechanics light saber, engineer too ?
 

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Can someone post a picture of this chamber? The other month I put an 820 airbox (with vector filter) into my 120+.

I removed the standard airbox (and mounts), but then routed the cold air feed into the black 'squiggly' piping that disappears behind the headlight area. Is this the chamber you're talking about?

Currently I get the nice grunty noise, however I'm not sure if the air from behind the headlight is the best source of cold air ;)

I was planning on running some venting from the grill to the filter, but I'm waiting for the right time to try it.

I'm selling an 820 airbox if anyone is interested! It's a little tatty (needs cleaned), and I'm currently in the Glasgow area (lo colgy, I'm across the water from you in Erskine).

Tara,

Andrew
 

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sort of - my system comes out of the filter goes left to a t junction - one pipe goes down into a box which i beleive is the plenium chamber and the other carrys on to under the light cluster ending in a smaller intake box

at the moment my viper intake hose is stuck over the end of the pipe which comes from the t junction part and since this is a lot smaller than my viper hose it is a long way from ideal although i do notice the difference already specially at high revs (i hit 7300 today and i lost all power for a second must have a rev limiter) though it feels like it could go to 8000 (not a good idea though)

i will hopefull attempt a good feed in the new year
 

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Any one had any updates on best place for the cold air feed?? :hiding:

I have the Taipan on at the moment but really could do with some ideas on where to put the cold air feed...

It looks like the piping that comes from the o/s/f headlight needs to partly come away (I.E the big plastic chamber that takes the hot air feed on the 160's as well) and then route the cold air pipe straight into the left over cold air pipe from the headlight (if all that made sense!)

Dont want to put the cold air pipe straight down through the engine bay incase water etc gets into it... even though it would have a long way to travel up. :blink2:
 

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macca160 said:
Any one had any updates on best place for the cold air feed?? :hiding:

I have the Taipan on at the moment but really could do with some ideas on where to put the cold air feed...

It looks like the piping that comes from the o/s/f headlight needs to partly come away (I.E the big plastic chamber that takes the hot air feed on the 160's as well) and then route the cold air pipe straight into the left over cold air pipe from the headlight (if all that made sense!)

Dont want to put the cold air pipe straight down through the engine bay incase water etc gets into it... even though it would have a long way to travel up. :blink2:
There is no problem putting it out the bottom, had mine there and had no trouble.
 
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