Just replaced the K&N cone that was on my S1 with an original airbox as the car is almost completely standard.

There seems to be a lot more heat under the bonnet with the original box back on, against when I have ran it with the K&N cone.

Is this normal - has anybody else had heat issues with an original ford airbox?

Power was definately down - still stupidly fast but not warp speed!

Fuel pump seems to be struggling to put enough fuel through now too - when I came to junctions I could hear the fuel pump at the back working harder (I can hear it as my parcel shelf, spare wheel and carpet are all out at the moment whilst I work on them)

Your opinions would be great.

Cheers,

Kieron