I'd got for the Mk3 1.9 1z lump tbh mate, you can get them relatively cheap now, and if u wanna run standard injection, u can get larger nozzles, and run silly power, or if u want an easy installation, find an early td pump, and run them as M-tdi, that way its all pump tuning.
I have heard and seen vids of the 1.9 1z's running at over 190bhp, but 120 ish is easy by just fitting new injector nozzle's and a re map :-)
And if u need a hand, i've done the conversion to 2x transporters now, so should be able to lend a hand :-)
Oh, and and fitting a mk4 lump is harder, due to them being harder to get hold of, more expensive, and more ecu's etc to paly with.
The 1.9 1Z engine is exactly the same as the 110GT TDI engine found in early mk4's anyway,all they run is larger nozzles (.9 somethin nozzle's on a 1z, and .203's on a GT TDI, then u can .216 for silly power )
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