nas55s,
I said before and I'll say it again if your looking to turbo a micra you could budget $5000 but it will blow out. Basic setup you'll a need turbo manifold = $500 - $800, turbo either t2,t25 or td04 = $150 - $300 secondhand $800 - $1000 new, exhaust and dump pipe = $1000 - $2000, oil/water lines = $70 - $100, intercooler and piping = $200 - $600, bov = $50 - $250, fuel pressure reg = $50 - $100 and sundries (bolts, clamps, gaskets, etc) = $200+ (this stuff adds up). That's for a basic setup now will that be reliable, probably not. Probably forgot some stuff as well.
Additional to this for reliability you would want, bigger injectors and fuel rail (sr20 are popular) = $200+ secondhand, bigger fuel pump = $50-$150, ECU = $2500+ (new, installed and tuned), oil cooler=$150+, bigger radiator= $150 - $800, HD clutch =$250.
Then to take it to the next level, lightened flywheel =$300-$500, bigger cams= $700-$1000, forged internals= $2000+, VLSD gearbox= $1000+.
I guess the cost to do a turbo conversion is based on how far you want to go, if you want to buy new or used parts, how much work you do yourself. I have done most the work myself and once complete the cost will be around the $15,000 mark as a guess I've lost count of the dollars I've dropped into this build (that's on the whole car, paint, suspension, brakes, interior, engine rebuild, etc)
Bottom line is it would be cheaper to buy a factory turbo car and mod that. But if your like me and just like Micra's then go nuts the more turbo micra's getting around the better if you ask me
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