RB,
I would like to offer a different point of view that is when TUV gives the certification, the car is still able to meet the required safety and enviromental conditions. It does not take into account relaibility of certain parts lke gearboxes and the entire drive train. When modding a car with serious gains, the brakes needs to be upgraded correspondingly as the availble braking torque from the stock brakes needs to cope with the extra accelerative forces offered by the souped up motor before it can start to decelerate the car. In addition the heat loads on the discs and pads may mean disc warps and brake fades especially when tracking.
IMO, even with TUV certification, I would recommend that the brakes be upgraded before the engine goes in. The gearbox and torque converter is a secondary issue that does not pose much of a safety consideration as a failure means no go. A failure with brakes means no stop...
JHLim
Personally I have played around with engine blocks and such to raise power. The rewards are very satisfying especially if the bottom end is well balanced and the head is properly sorted out. If you had the budget to fully convert your car then you should go for it and perform a complete re-build with a blue printed engine (fully balanced if possible) with a ported, skimmed and flowed head. The ECU too should be swapped as the fueling requirements are different. In addition, install a piggyback to fine tune the AFR and ignition to take advantage of the higher compression. End state, you will out perform the stock 3.0 engine and the very big plus point is that your engine is completely new. (no oil leaks, compression problems, dirty valves, carbon filled cyl heads..... you catch my drift?) Of course if you are so lucky to get into an accident, the insurance companies will never pay out if they find out.
that's why i now good boy....
adding a turbo in is considerd an exhaust mod and carries a fine of $500 if I can remember correctly. Adding a SC is considered an engine mod and carries a fine of $2000. Changing your engine CC is considered cheating and is a criminal offence....
In this country the engine conversion bit is a little scary but in other countries where the taxation is not based on CC then the engine swap sounds very very delicious....
just my 2 cents worth.