4g13 is not powerful enof for me so always rev high and also always do burnout using ori 13inch rims and tires b4 the rims bengkok and upgrade to 16inch... those ori rim and tyres often make me accidentally drift on wet road especially when cornering too fast (with lowered spring and absorber plus front strut bar)... real drift... not powerslide or oversteer... the lowered iswara is stable when i cornering that i can do those drift action like reflect action when the rear tires skid accidentally...  after changing to 16 inch rims with 205/45/r16 tyres the iswara become so stable that i cannot perform many act on wet road... dont even think to do it on dry road...

the lowered spring is too hard that i don't felt comfort when driving on bumpy road that after the lowered absorber (4get what brand liao) kong then i chage back to apm shock absorber with normal spring... this time the car become so damn high that the car will roll and twist when cornering that i felt that the car want to lost control and turn over when hard cornering... for example, if i can turn the roundabout with 70kmh steadily without skid with lowered spring and absorber but with normal absorber and higher spring i can just turn the same roundabout with speed 55 - 60kmh and the car will swing like hell when i do cornering...

at first i want to change the engine to 4g63t and "play" with my car without endorsement ( coz the engine mounting will surely be relocated if not mistaken and it is impossible for the car to pass puspakom endorsement now without...) but get stopped by my parents... after negotiate with them then they allowed me to modify my car legally... i had put a budget of rm10k ( save from ang pow money and my work) in modifying my car...

now plan to change to 4g91, coz still in range (1300 * 125% = 1625cc)...
actually i want to upgrade to 4g92 mivec engine for more hp but realy hard to find that engine in sarawak...

i want to ask is wat i can modify onto the 4g91 engine so that i can plug in turbo charger or supercharger??? does those turbo boost help in increasing the hp of this engine (without modifying the engine)???

for what i know is illegal to change the engine block... so for my case can i just bore the cylinder to fit bigger piston if i want to turbocharge the engine??? which piston is suitable for this, 4g93,4g63 or toyota piston???
did i need to change also the gear box??? what turbo kit or supercharger kit is suitable or can be modified to fit into my car???

my iswara now got 16 inch rims and i plan to upgrade also the brake system from stock to vr4 front and rear disc brake... can i use those aftermarket brake disc which is bigger and with holes which is more 'sporty' look??? can suggest what brand is better???

if i change the engine to 4g91 then can i stick back to the 16inch rims or i need to change to 15inch rims for better acceleration???

i had already put on UR front strut bar in my car for better stability when cornering but i still don't satisfied by the stability of my car... what other important bars i hv to put on to increase the stability of the car??? did bigger front and rear anti roll bars help???

if i change the engine i need to change the whole ekzos system also... to increase the engine performance did i need to change the original extractor??? what is the difference between the extractor 4 to 2 to 1 and extractor 4 to 1 in increasing the engine performance??? how big is the piping if i need to have better fc and also increase in engine performance??? which type of muffler i can use??? what is the differences between the muffler with over tip or round tip???

that's all i want to ask now... thank you for your advice...