If you really want to spend some money (as I feel it's burning a hole in your pocket

)
Why don't you fit a bespoke inlet manifold with throttle bodies and a bespoke engine management system without a catalyst like the kit-cars have.
Speak to Burton Engineering

You'll have to take it all off for MOT

or re-homoligate the car as a kit car (Q-Plate) but you'd have 190 BHP before you even looked at the cams or upgrading to 2300cc or even fitting a Super/turbo (
then you could have an intercooler).
If you fitted an intercooler to an N/A car you would loose about 20BHP
