Comments by "Bond25" (@Bond2025) on "$800 vs $1500 Hydraulic Handbrake" video.

I would not use or recommend K&N. They refused to honour the warranty for damage caused to a MAF sensor from oil proved to be from their product over it. The air filter I used reduced performance, but you could hear the air being restricted through it. Stick to paper elements that are 13 times the surface area, pass far more filtered air than the car needs and doesn't block up in months and degrade performance. On s rolling road, testing cars of all types from the 80s, not one was any better with a K&N. I paid for the products as I refused to be paid and sent a script to read out. I tried many makes including pipercross. No increase in performance, but the foam sagged. One thing in common with all oil and mesh filters is how small the surface area is and how holes need to be 13 times bigger to flow the same amount of air as a paper filter, it means dirt and dust goes through as it doesn't meet manufacturers tolerances.
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