I can't make up my mind what to do with the induction system,I had a K&N 57I fitted sounded good maybe a little noisy, then I heard cone filters cause damage from the induction of hot air, so now I an back to the standard air box with a Jetex high flow filter in it. Basically can anyone suggest a better setup? (UK MY98)

The hot air is not a problem mechanically, with a cone.

The colder the air, the more densley packed the air particles, thus the combustion effect is increased. Its why your car will feel sluggish on a hot day (may be teaching you to suck eggs here)

With the standard air box, you are reasonably well sealed off from the heat build up in the engine bay.

With a cone filter you are exposed to the big heat under the bonnet, however, the air entering it will only really be hot while the car is stationary. Once moving, cooler air will be circulated. What may help is a little mini scoop, replacing the grill on the bonnet above the filter. A number of people use these to direct air in.

The problem with cone filters is that most of them have rubbish filtration, Blitz, HKS etc. And nerly all have caused MAF failure. (Air flow sensor near the air box) the problem with that failing is it can cause the car to run lean without you knowing. Most cone filters will lean out the mixture to some degree, so add that to a lean running MAF and you're looking at a buggered engine.

If you have to have one, the K&N is tried and tested and has caused much fewer MAF failures.

Guess you have to ask why you want one. If probably wont give hardly any power gain (only from leaning the mixture) and normally drops the torque. (initial warm air pull??)

If you have big mods that require more fuelling, and thus more air, then fine. I think most of the big power people will use them.

Most will advise you to stick with a good panel, ie K&N or TSL's green filter.

Hope this helps :)

MB

[Edited by Dark Blue Mark - 6/23/2003 9:37:21 PM]

[Edited by Dark Blue Mark - 6/24/2003 11:09:19 AM]

Thanks,DBM,It helped me too.I was one of them who went out and bought K&N cone and buggered the airflow meter.

But - if were discussing the MY98 here - earlier cars with hot wire MAFs are much less susceptible to problems.

There are drawbacks with the OEM airbox too - once heatsoaked it takes longer to cool than a cone filter!

Andrew...

HMMM Glad I read this thread - not !!!

Just ordered a K&N 57i for MY97. Anything I should be aware of ???

As Andrew said, the MY99 / 00 are much more of a problem, but earlier ones can still fail.

Id still question the need for it though. The noise is quite nice, apart from when you let the foot off- sounds like an asthma attack!

Done think they do much else though. If you look at the surface area of some of them, they're not much bigger than a panel! Ok, they let more air in because of the higher micron mesh size.

Wouldn't worry about the K&N one though. Also its just my opinion, many have the Blitz and HKS, and swear by them. Not many though ;)

MB

[Edited by Dark Blue Mark - 6/24/2003 11:10:23 AM]

The problem with the OEM airbox is it's quite restictive, the actual size of the filter is less important. The airbox also retains a hell of a lot of heat... as said before the induction kit only gets hot air while stationary. Once moving the air under the bonnet is nice and cool.

I've had a k+n now for over two years without any problem. On pre99 cars i really wouldn't worry (i.e hot wire MAFS). If you've got any sort of aspirations for power than an induction kit is a must (have you ever seen a front mouted intercooler with an OEM airbox?).

Tony.

Thanks Tony

I am happy once again :) :) :) :)

What effect would drilling holes in the OEM airbox have then? If my way of thinking is correct then you will have more cold air, less heat retention and better filtration than a cone.

I know people who have done this in the past on lesser cars but never on a scoob.

Any thoughts?


Steve

Tonys right, and as I said, they are required when you go for big mods.

Might sound a bit odd if you drill the holes?! Cant see too much of a problem, but don't think it would make a great deal of difference. If you put too many holes in, you might as well go for an induction kit anyway :)

If someone knows of an induction cone which doesn't sound crap when you let your foot off, I might be tempted :)

MB

[Edited by Dark Blue Mark - 6/24/2003 4:22:35 PM]

If you relocate the cone into the wing it's a bit quieter, and gets more cold air!

Andrew...

Now thats what I like, a bit of lateral thinking. Picking up my induction kit tonight :)

Drilling holes in the airbox is a trick employed by boy racers who want the sound of an induction kit but don't wanna pay for one! It basically lets air in without going through the resonators etc giving the deep induction roar you get with a kit.

Doubt it will show any benefits, you'll still be taking in warm air from the engine compartment although there will be none of the problems to the MAF due to poor filtration or vibrations. Just make sure you only drill holes on the bottom half not on the filtered side! ;)

just remove the plastic trim from the front of the wheelarch/under the front bumper to reveal the bottom of the resonator drill a two inch hole in it and use some flexible pipe from there to the slots in the bumper under the indicator then fit a panel filter and block off the origional air feed under the bonnet,gaurenteed cold air replace the trim with a little cutting and bobs yer uncle:)