Hello Colin...K&N air filter with blow through lid system best deal out there
system delivers more fresh air to your engine...via your hood scoop forcing fresh air into top of carb. Yes that boonet / hood scoop does provide a few free ponies. Using the blow through lid takes advantage of the scoops ram air effect.
Using these K&N systems will also save you money as they are reuseable
you just wash them and respray them & reload them and off you go.
Not as with paper element filters you toss and buy new one over the years with the K&N you save big dosh and score a few free ponies to boot.
We use 14" dia drop style kits no clearance issues in most Cobra kits except G/D...Cobras very tight those are 3" filter with drop base will not fit
you need 2" element with drop base and trim'n of base neck nessasary to clear hood..with air gap intakes and stock hood scope.
Cheers! my 1 pence worth
Dr,Dee
PS Kits go for approx 65 GBP approx
