- Even if there could be backfiring from unburnt fuel, as Mr. T states, most of the times backfiring comes from valve overlap: or, at least, I'd say most of the forumers agreed on that in the thread on "variable valve timing".
I repost some pictures from that thread:
Looking for the flames only? Gadget at Gizmodo
Performance camshaft: overlap visible (both valves are open when the blue and red circles overlap, thus fuel goes directly from intake to exhaust). Check the animation at http://auto.howstuffworks.com/camshaft.htm
- The S-curves shown in the video are circular curves and have no spiral transitions. The video shows beautifully that, in the short straight between the first and the second curve, there is the transition of the superelevation: the road surface is "twisted" between the curves, on a small straight.
Thus the road has a slope to the left of the image, on the entrance of the second curve. The end result is that djones feels that the road is pushing him to the left on the entrance of the second, right-hand curve. Most drivers that I know are not conscious of that.
Besides, the inner part of the second curve, where the apex is, has its own superelevation and concentrates the water on this apex, another thing you avoid by instinct.
So, I'd say djones takes a normal line, caused in part by the old design of the road and the rain.
That and I had no idea at all what corners/cambers/bumps/puddles were coming next.
)