KO3s mate. KO4 variant will not fit. Unless you change the manifold/downpipe, even then on on RHD Ibizas the DP will foul the steering rack. So major changes needed. KO3s will bolt straight on and with all the goodies you could see upto 250bhp 270lbft. IIRC the KO4-051 will bolt straight on but are known to be very weak, and you would still only see the power of a KO3s..
Hope this helps.
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