k series airbox or big foam thing?

[fantombiker]

I have k series vhpd with Bernard Scouse airbox. The TB trumpets are about 90mm and seem to be very close to the wall of the air box. This was proved to be restrictive on the rolling road and released 10bhp when removed. I was thinking of fitting one of those big foam air filters and cutting a hole in the bonnet.Any comments as to whether this is a good idea?

[Tango7]

Depends on whether you will be going on track or not. No cut out and keeping a BS air box will be quieter than a foam filter protruding through the bonnet. On the whole, induction noise issues can be worst to resolve than exhaust noise.

[Shaun_E]

Which BS airbox have you got? The early one had a small 63mm IIRC opening and the later one has an 80mm opening. The later one is much bigger and will be less restrictive. It worked fine for me with 90mm trumpets.