1.2 DIG T with Shell V-nitro fuel

[pistnbroke]

The point with combustion is that the pressure must be its highest after TDC to push the piston down.This is done with the knock sensor which advances the igniton to the knock point and then retards a little only to advance again. so for any load speed the timing of the spark or injection is adjusted to be just short of knock. Spark may ignite the fuel 45 deg (crank angle) before TDC to acheive this. There is no explosion forget that but burning out from the plug in the form of a flame front..

[jonceebee]

This is an article relating to high octane fuel. It does mention the advantages of cars with turbo or super chargers fitted.http://www.moneysupermarket.com/car-ins ... -unleaded/

[Iandee]

Searching for something else I was interested to find the subject of this topic, being fairly new to my Qashqai and the 1.2 engine with Shel vitro etc, but disappointed that it degenerated from the subject. Then I noticed the posts were about in 2014. Has anyone anything to contribute to this topics subject bearing in mind it's now 2017 ?

[Bob d]

With my previous car (1.9tdi SEAT) I could always notice the difference between my local Tesco's fuel and, say, Esso. So by habit I tended to fill the QQ with a mainstream branded fuel but more recently thought I'd give the Tesco stuff a go but this coincided with the onset of cold weather so it was difficult to assess how the different fuel brand was performing. At least until last week, when the tank was getting a little too low and I refilled with some bog standard Shell stuff, hmm the difference was indeed noticeable. I'd initially assumed that a small but noticeable loss of low end torque was down to the cold weather rather than the supermarket stuff, not so, the weather is still cold but the refill with branded fuel noticeably restored low end torque and makes the whole driving experience easier. I'll be sticking with the main brands in future.