What is the famous "K&N filter" which everyone talks about so much ? And what is the Petes tuning box ? are they of any use ? do they increase performance/initial pick-up/speed? do they lower fuel-efficiency of the car? Any other pros & cons ?
Have been hearing abt these things a lot but always wondered what these "special" things are ! [thinking]
There is more to air intakes than it meets the eye. Just replacing the filter element with a so called 'performance filter' will gain little to nothing.
A lot of people make the mistake to rave about the replacement filter after swapping it with a clogged up paper element.
You can get quite a bit more out of the engine with a dedicated air intake revision. On dedicated revisions we have measured on turbo Diesels up to 5% peak power and up to 35% more low end torque. On petrol application we have measured up to 11% peak power improvement and low end tor in some applications increased by over 40%.
A properly designed air intake revision will improve fuel efficiency. A recent long term test I have made in Ahmedabad with my own development showed on the Linea T-Jet 8% lower fuel consumption.
Tuning boxes are only of some use on turbo Diesel engines. On turbo petrols they are questionable and on normally aspirated engines are an absolute waste of time.