come on tight arse jks
plugs cost like $4 * 4 =$16, you have to have the car running when you put carbie cleaner in there.
I had a problem with my carbie the other week and it turned out to be some shit stuck in the jets.
a webber will give you a performance gain if tuned right get a pro to do it (a carbie place will but ask around for qoutes).
It would be even better if you got your manifold + head ported
but then your talkin $$$ get a decent air cleaner for a cheap upgrade