Intercooler is a must if you are looking for more power. Om602 stock turbo is pretty small for any horsepower increase so if you can get somewhere om603 stock kkk turbo that should be enough for 150hp.
So that would be an intercooler+stock om603 turbo+increasing fuel load on the ip for the ~150hp or just the i/c+turbo?
Can I use anyother turbos like one from a BMW 525tds (93-95) , VAG 2.5tdi (96-99) or from a 3.0L off road engine (like a pajero)?
6000rpm is usually safe if you drive your car nice and don´t rev it up on purpose. You don´t usually have to use so much rpm with stock IP.
Many times when my engine is up to temp, ~83*c I like to rev first and second. Is that considered "not nice"? If I have more RPMs I can use for a longer time the lower gears so better acceleration and easier driving on the mountains.
Hope this helps you.
No one messes with their engines in Albania so I'm pretty much the first one "experimenting". Any help is valuable, especially if it helps achieving good results with less headaches, if you know what I mean

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Thanks a lot and please keep the English Forums alive. What you do with your cars amazes me

. I feel like a little child in the circus looking a magician doing tricks

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Deni