firstly id like to introduce myself my name is martin im from (sunny?) Wales and ive just bought a 94 WRX ..in fact i pick it up tomorrow

im not sure if this is the right topic page but in order to get insured i have to declare the mods to this vehicle

it has the green mushroom HKS intake and a full st/st exhaust

my insurer wants to know what BHP increase each of these mods will give the car..BUT...how do i find this out...ive tried some websites that sell HKS products but they dont give gains...and how the hell do i find the gain of an exhaust system that i dont even know what brand it is

any websites or personal expeience would be most appretiated

thanx in advance