Servicing wont save your engine, of course a well serviced engine will have an increased time til failure, but everything fails eventually. All parts that undergo cyclic load suffer from something called metal fatigue, by adding boost will increase temperatures and stress loads, in turn increasing metal fatigue and reducing time til failure. Increasing power and torque can drastically reduce the life of a standard part because of the higher bending loads on them, and the following loss of tensile strength because of fatigue.
The B18c4 was designed to run at 170bhp for X amount of miles until failure. There is no doubt that this engine is more than strong enough to withstand some boost BUT only so much boost until eventually it fails. Think about a metal coat hangar, bend it backwards and forwards continually, It slowly weakens and then breaks. The more you bend it, the quicker it weakens and breaks. This is exactly the same process that the conrods, pistons, crank etc, and everything else sustain when increasing stress loads.
Think about a plane that you know has been serviced well, as all of them are, but has used the same engine for X amount of miles but then the airline decided, to get to the destination quicker it would increase the thrust by 100% but then life expectancy becomes unknown would you still board it?.
I'm not against your build and I think it is an achievement to make 370bhp on a stock B18c4 BUT it is at much higher risk than if it was running less boost/power.
Like you say traction is the next issue, a proper diff and tyres will help you along the way. Then its time to think about the stresses on the gears especially dragging the car.
Good Luck!
Ben