Thread: 300tdi pump advance 1.6mm lift

I have been disappointed before.
Seems some engines like it and others perform worse.

I put a Boost Ring on my 300Tdi IP. The Boost Ring is a spacer that allows a few more millimeters of plunger travel for an Advance mechanism in the IP. The IP has some dynamic advance, where the injector timing is adanced at higher speed, and the Boost Ring gives it the potential of more range (advance).

The mod is about $50 and 30min, it's awkward but not hard to fit. I have a VNT and Fuel Pin mod on my Tdi, and the Boost Ring seemed to eliminate a lot of smoke on heavy load. It still puffs on start up, but that's just how the Bosch IP is designed and doesn't have anything to do with advance.

I noticed that the car is a little bit noiser on initial start up (maybe a I should check the tappets), but it quietens down nicely when warm. Getting from 100kph to 120kph for overtaking (with the Overdrive engaged) is now a lot easier.

Just my two cents:

200tdi / 300tdi lift pump advance - don't change it from factory spec. I have advanced and retarded the timing and seen no noticeable increase or decrease in performance, so I now set it with the dial to factory spec and that's that.

Research has been done by many folks (academics/scientists) over many years to see how injection timing affects the amount of energy released by diesel fuel on combustion. It has been clearly shown that there is a non-linear relationship between timing and energy released. Non-linear meaning it matters, but not in a simple "the more you advance the more power you get". There is usually a peak somewhere as you vary timing, and the peak varies due to a number of factors related to engine design.

The problem, though, is that this relatively small change in energy released by the fuel is dwarfed by the fact that the combustion heat/pressure moves around with the injection timing. Basically, the combustion happens later or earlier depending on the timing, and there's really only one place where the engine will work the best. So if you change the timing just a degree or two either way, you're not noticeably changing the power from the engine. If you adjust it more than a few degrees to get noticeable effects, then the negative effects of being out of time with the pistons and stroke start to take over.

Heat-release-rate-mean-gas-temperature-and-incylinder-pressure-of-the-diesel-single.jpg