BDS Engineering - Examples of our work Lightening Nissan March Flywheel Our customer approached us with his stock Nissan March flywheel. Its standard mass of around 4KG was successfully reduced to around 2.5KG. This saved the customer ordering a custom made one in from Japan (at a significant cost) and ours weighed in at over half a kilo lighter than the custom one! Re-Grinding and Seating Skyline Valves Our customer approached us with a partially completed skyline engine rebuild. The block was "as original" and the valves needed to be reground and re-seated. We were able to very precisely grind and seat all the valves, checking each for a good seal using the vacuum pump and pressure gauge.