engine bore help
 

Hi, I have a 1964 bug....with a stock 1300cc engine...how far over can I bore my engine and what all do I need to make my bug scream???? I want to kick my friends butt....he has a 1971 datsun 510 2 door with an L20b he is bushing around 100 hp to the wheels...here is his car... http://www.cardomain.com/memberpage/484438 ...
I am like 40 hp ....plz...any info would help p.s. I am considering a budget of about 1000 dollars maby 1500....THANKS