Quote: Originally posted by Jason C on 20 August 2004
Theres a greater air to fuel ratio as the aftermarket filter flows air at a greater rate. The car therefore runs lean. The greater the ability of the IK to flow air, the leaner the mix. Depending on the map used, it could be a problem throughout the rev range or points through it.
Warm / hot air being sucked in to the IK will also cause problems as the density decreases so you get less O2 for a given volume.
Yes i know what you are saying but I dont think that at 700 rpm the flow rate on an IK will be noticibly different to a paper filter.
for the volume of air required at idle i cant see a paper filter being any more restrictive than an IK. it will be when the engine demmands a large capacity of air that it physically can not get through the paper quick enough. that is when the less restrictive IK is useful. high revs
for example i can squirt 1 milli-litre of water at the same speed through a straw as i can through a hose pipe. the hose pipe is no less restricive than a straw at low volume. try to pass 1 litre through the straw and it will ristrict the flow. through the hose pipe no problems.
so i dont think that an IK will make the engine run lean at idle, at higher revs maybe. i also thought that the ECU should have sufficient range to adjust the fuelling to cope with an IK. esp on a small capacity engine.