K9F wrote:

For the last few days I had to revert to standard and remove the 12mm blank I had fitted! Disgustingly I only returned 26.5 mpg, that's the lowest I've got since I first tried fitting them! Service now done the 10mm is now fitted and we'll see how I get on! Map goes back on next Tuesday too! Yippee!

id love to be getting 26.5 mpg!! im just about to drop down to the 10mm plate but at the moment im only getting about 21mpg on a good run.

Ive got the BAS tune (best mod so far) set to "POWERRRRR" (as MR. Clarkson would say) and currently the 12mm plate fitted, ive noticed a smoother feel to the engine and even a slight increase in pull through the gears but sadly no mpg figures like others have reported.

to be honest though 21mpg may well be an increase for me, i have a bit of a heavy right foot and ive never really checked the economy until now

Anyway 21mpg is way better than i got out of the merc so i still feel like a fully fledged member of greenpeace im off to hug a tree Puma 2.2 90 Stationwagon

K9F wrote:

In my 90 I peaked at about 31.5 mpg! Believe Mr Woo got 34???

my average at the min with a 12mm blank in is 27.5 that was yesturdays test with my new BIG COUNTRY full lengh roof rack. . I will let you all know a full comp list of my mpgs .vs. blank sizes when i return from my trip to france, switzerland and italy when i will have coverd a good few tho (k).  2008 110 County utility
ex 1988 defender 90 ,td
ex 1970 series III

big steve wrote:

whats the smallest hole being used so far im still on ??

steve

p.s robo what hapeended abt the st/steel fuel guard thing ??

12mm hole at the min steve that seems to suit my engine well ! no light on for months now!.

work in progress with the fuel cooler guards steve just short of one thing (time!) at the min busy getting ready for my summer trip to italy. Will post some pics as soon as they are ready .  2008 110 County utility
ex 1988 defender 90 ,td
ex 1970 series III

dgardel wrote:

The EGR valve recirculate, in same engine rpm, Temp, and load conditions, controlled part of exhaust gases to the inlet manifold.

In this way the engine run with lower combustion temperature and produce less NOx
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In modern diesel engines, the EGR gas is cooled through a heat exchanger to allow the introduction of a greater mass of recirculated gas. Unlike SI engines, diesels are not limited by the need for a contiguous flamefront; furthermore, since diesels always operate with excess air, they benefit from EGR rates as high as 50% (at idle, where there is otherwise a very large amount of excess air) in controlling NOx emissions.
Since diesel engines are unthrottled, EGR does not lower throttling losses in the way that it does for SI engines (see above). However, exhaust gas (largely carbon dioxide and water vapor) has a higher specific heat than air, and so it still serves to lower peak combustion temperatures. There are trade offs however. Adding EGR to a diesel reduces the specific heat ratio of the combustion gases in the power stroke. This reduces the amount of power that can be extracted by the piston. EGR also tends to reduce the amount of fuel burned in the power stroke. This is evident by the increase in particulate emissions that corresponds to an increase in EGR. Particulate matter (mainly carbon) that is not burned in the power stroke is wasted energy. Stricter regulations on particulate matter(PM) call for further emission controls to be introduced to compensate for the PM emissions introduced by EGR. The most common is particulate filters in the exhaust system that result in reduced fuel efficiency. Since EGR increases the amount of PM that must be dealt with and reduces the exhaust gas temperatures and available oxygen these filters need to function properly to burn off soot, automakers have had to consider injecting fuel and air directly into the exhaust system to keep these filters from plugging up.

EGR deletion
EGR deletion in diesel engines is considered justifiable by a wide range of people, including the environmentally conscious. Although deleting the EGR system results in increased NOx level; hydrocarbon emissions, particulates, carbon monoxide and carbon dioxide are drastically reduced. Furthermore, EGR deletion results in an increase in fuel economy as high as 25%. Exhaust gas recirculated back into the cylinders adds wear-inducing contaminants and causes an increase engine oil acidity, which can result in an inefficient, poorly running engine. The increased level of soot also creates the need for diesel particulate filters to prevent environmental contamination.