Tuning!!!!!

hi all....

im new to this site so im sorry if i sound like a twat...

i am not new to cars as i am a audio technition and electrician but i have not got all the experiance about engines....

i would like to know how to tune my car without upgradeing it I.E.... k&n or exhaust... just a few tweaks for me to do on it as now.... i have a vauxhall cavalier 2.0 I 8v

if anyone can help itl be brill!!!!

cheers

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