wat u saying are true. but in a long run, heard ppl say will crack your extractor.
remember, every item has its pros n cons.

Dear all seniors,

after reading 26 pages, i guez wat i can do to increase the performance for my Wira 1.5 (A) Carb. is as follows;

1.) Change ori extractor to powerzone 4-2-1
2.) Chg air filter to at least aftermarket drop-in or open-pod type. Powerzone air intake manifold, any comment ?
3.) i think wira stock muffler is already s-flow type, rite?
4.) is ori exhaust pipe ok or not ? need changes ?
5.) What about ignition system ? any effect in terms of power & FC performance ? What can be done here ?
6.) Last would be to replace stock camshaft to powerzone camshaft ? 

Wonder how much increase in perfomace would it be after done all these upgrades ?

Can advise a little bit more ?

jianhang