The first thing that became clear in taking down the Bmw M6 was bore and stroke. “It was just sort of begging for stroke.” It require a bit of bore too. So, Dinan stroked it to 83 mm and bored it to 93 mm.Boring the V10 from the stock 5.0 liters to 5.7 was tricky, since the cylinder walls were lined with silicon-saturated aluminum alloy. Dinan’s CNC bore equipment were equal to the task.“The silicon’s impregnated deep enough into the block that you can bore out into the aluminum and still have the silicon. We had actually perfected all this technique on the racing engine.”