Turbohot

Hello!I got two mods done recently to my 2000AWD Turbo scoob.K&M induction kit + Le Mans Dumpvalve.I got rid of the dumpvave coz it was dumping too much air out even when it wasn't supposed to.Now I have got a prob with the car jolting at high speed in 5th gear(see my other topics).I rang up RC developments today.They say K&M are bad news.They had had many ill scoobs going in for the same fault caused by K&M.It has f**ked the air flow which will cost me(th part itself)178 quid + vat!I feel sick but please,be warned before you put K&M in.It did perform great but caused a fault to other part.

ustolemyname??stevieturbo

iTrader: (1)

K&M ?? Do you mean K+N ??
Airflow meters are as far as I know around £60-70 from the Subaru dealer. Do a search here, it has been covered many times.
K+N I think are usually quite good. It can be the fitting process that causes failure. Any jolting about or movement seems to wreck them, as much as dirty air, or dodgy filters.
They are just very fragile.

Syxx - Pac

hi, ive got a blitz induction kit and it sounds great but after speaking to a few people someone said that having an induction kit like blitz or k&n could end up causing damage because it sucks in hot air from the engine bay rather than the panel filters that get cold air from the outside. i dont know how much this is true but i think im gonna risk it coz it sounds brilliant(no need for a DV!)

nom

The added excitement with the Blitz is that it doesn't filter very well, so your engine will suffer, particularly the turbo's turbine blades

The K&N has, AFAIK, had a very good track record - not one failure as a fault of the filter, although it is tricky to tell as the MAFs of MY99/00s would go wrong if you left them in a sealed airtight container .
I think the 'under bonnet heat' problem only arises if you're a traffic-light GP nut - after a minute of free-flowing traffic the under-bonnet temps have dropped considerably, and your main problem is the heat-soak into the TMIC if you have one.

Dark Blue Mark

Jolting is more likely to be the dump valve being fitted / re-fitted incorrectly. I had too weak a spring on mine and it would surge under very light throttle and de-cellaration.

Nowt wrong with the K&N if you have to have a cone filter. I think they all sound **** when you let the foot off the throttle though.

MB

dan rolfe

wot about the piper cross viper kit?? has n e 1 tryed it? do u think it would work well?

Chris L

Don't get fooled by the 'sucking in hot air from the engine bay' lark. When the car is moving the actual temp of the air moving across the engine bay will be little different to air drawn in from outside the car. There will be a considerable difference if the car is stationary or moving at very low speeds. If you think about it, there are loads of places that air can get into the engine bay. Now consider how long it would take for the air to travel through the engine bay if you are moving at 30 or 40 or more mph. There is very little time for the air to heat up.

What is considerably more important, is the actual fitting of the induction kit. This is where most of the problems will occur - especially with the HKS / Blitz type mushroom kits.

Chris

Rich TurboUK

Hi,
Just to add to the confusion, I have just had my MAF fail, suggested reason also recent fitting of K+N. I think from what I have read that if your MAF is getting tired, fitting an induction kit can very well cause problems (my car has 130,000 miles!), contaminating the hot wire with cr*p. It was explained to me like the difference between the filtration of a teabag compared to a string vest! although, like anything it is a bit "luck of the draw". Like any engine performance mod this will increase stress on various components, it is the usual weigh-up of gains versus potential problems.
As far as prices go, I think you will find that pre '98 cars had a sealed unit costing 180+vat ish and later cars have a replaceable element @ 80 ish.
I would dearly love to re-fit K+N, but cannot afford to take the risk, so will now go for an ITG panel filter, which flows as well, if not better anyway, just doesn't sound so good!

Cheers, Rich

Brun

Subaru stopped fitting ITG panels as part of the ppp due to maf issues i believe.
As stated above, i'm yet to hear of a stuffed maf when K&N is used

Dark Blue Mark

Chris,

Im not sure the air is cooler when moving, when using a cone. The standard airbox prevents heat soak and the volume going through is probably not hugely smaller. Fitting a mini scoop will help a great deal though.

I don't like cones much, purely from the noise, but feel the standard airbox is adequate unless you have big mods, more fuelling etc.

MB

Dark Blue Mark

Realised that didnt make sense. The air temps when moving will be the same with a cone as with the standard box I would have thought. Surface area of the cone and level of filtration will mean the cone gets more volume of air in.

MB

Bob Rawle

K & N is not known to cause maf problems, in fact the contrary, it maintains maf callibration pretty well, there is very little difference in intake temp on the move as has been said, you would get heat soak sooner in traffic but ultimately it ends up the same, with an air box it take a lot longer to cool down as the box becomes a heat resevoir so the cone has the advantage there.

bob

spence7

Aside from the temp issues (or not as the case may be) I thought that the extra volume of air allowed in through more surface area and less dense filtration....means mixture leans out and can cause boost spike and subsequent occasional fuel-cut situations ? Hence shouldn't be done unless fuel is remapped to cure the lean, and the fuel-cut point is increased with a boost controller type gadget.

Tone Loc

iTrader: (1)

Spence, the wholepoint of the MAF sensor is to monitor how much air is going into the engine. More air means the ecu sees a higher load value so puts more fuel in. Problems arise when the induction kit fitted throws the MAF calibartion out. So for a given air flow the MAF voltage the ecu sees is lower so it uses a lower load value than it really should be doing.

Boost spikes shouldn't be a problem either.... not sure why this would be caused by an induction kit?

I have a K+N and it is a little leaner than i'd like during spool up but it's bean on for over two years now without problems.

Tony.

Turbohot

My god,my head is battered ! Anyhow,The vehicle goes in tomorrow for the diagnosis.I will keep you posted with what comes out to be the fault and what caused it.

MurrayZA

Over oiling the element can also cause problems to the air flow sensor.