mudmuncher Posted May 24, 2011 Share Posted May 24, 2011 Hi all Need your help guys I am running a defender 300tdi it has Fuel pump tweaked Large intercooler And the boost has been increased on the turbo actuator rod I am really pleased with the power !! Right my turbo oil seals went big time the turbo worked fine just pumping oil out everywhere My problem Is I have invested in a new turbo and i am not sure if I should shorten the rod for extra boost to match the fueling etc I want to do it as the power was nice but I don't want to kill the new turbo By shorting it a bit would it have much of a impact on the reliabity of the turbo or are they made strong enough to take a little extra Would gratefully like any advise please Many thanks Chris Quote Link to comment Share on other sites More sharing options...
rusty_wingnut Posted May 25, 2011 Share Posted May 25, 2011 mine is wound as far as the thread goes. Quote Link to comment Share on other sites More sharing options...
Snagger Posted May 25, 2011 Share Posted May 25, 2011 The higher the boost, the higher the fuelling. Both will increase temperatures and pressures within the engine and the turbine section of the turbo charger. There will be a safety margin built in by LR, so moderate adjustment and over-boosting shouldn't do too much harm unless you regularly drive hard, but large adjustments will certainly reduce engine and turbo longevity. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 25, 2011 Share Posted May 25, 2011 If you want to do this it's probably worth adding an exhaust gas temperature gauge so you can monitor the temperatures and see if you are over doing it. On the 300tdi you can mount the sensor using the EGR blanking plate. Somewhere around 700C is seen to be about the max temp before you damage anything, if you start going over it just easing off on your right foot will bring it down quick enough.... It's also quite interesting to watch in a geeky way :-) Quote Link to comment Share on other sites More sharing options...
rusty_wingnut Posted May 25, 2011 Share Posted May 25, 2011 mine boosts to 1.2bar, I have a good intercooler and pipework with no leaks. The diaphragm in the pump is a1/4 turn up. the EGT never gets above 650. Been like it for years now. Quote Link to comment Share on other sites More sharing options...
mudmuncher Posted May 25, 2011 Author Share Posted May 25, 2011 Cheers guys I have an egt gauge fitted and flat out uphill she only just touches 550 ! So I would say the tweaks are only mild which is good enough for me I think I will adjust the new turbo to the same as the old one was as there is no smoke and the egt temps are not that high I think my mild tunning shouldnt have that much affect on the life of the new turbo Do you guys agree ? Many thanks Chris Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 25, 2011 Share Posted May 25, 2011 Interesting, I've just fitted EGT,tacho and boost gauges with the hope to start 'playing' with a few settings. Currently I have a standard intercooler, I'm measuring about 0.9bar at the manifold and I believe the pump hasn't been played with (no black smoke except when starting) anyway the max temps I see are 650c on a long motorway hill foot to the floor. I assume the large intercooler is why your max temps are much lower than mine and rustys's. I had a bit of a google and it seems lack of oil and high temperatures kill turbos.... I can't find any mention of excessive pressure alone killing them .... Anyone of the competition guys care to answer that one? Quote Link to comment Share on other sites More sharing options...
cackshifter Posted May 25, 2011 Share Posted May 25, 2011 I think higher boost tends to wear the the thrust bearing, so maybe not immediately noticeable, but isn't that why people fit 360 deg bearings? Nigel Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 25, 2011 Share Posted May 25, 2011 I think higher boost tends to wear the the thrust bearing, so maybe not immediately noticeable, but isn't that why people fit 360 deg bearings? Nigel Just read an advert for 360 deg bearings and it says it allows you to run higher boost pressures .... so I guess that makes you right Nigel Cheers for that I'm guessing a worn thrust bearing can cause the turbos oil seals to fail which would possibly explain the failure of the original turbo? or maybe it just happened to be it's 'time' Quote Link to comment Share on other sites More sharing options...
inaine Posted May 25, 2011 Share Posted May 25, 2011 turn it up, just remember to let it tick over for 10 seconds or so to let the turbo wind down from 100,000 rpm! thats what kills the older style turbos. modern engines have aux electric water pumps to keep the engine and the turbo cool for 10 mins after you shut it off. Quote Link to comment Share on other sites More sharing options...
discomikey Posted May 25, 2011 Share Posted May 25, 2011 id run it in for a few hundred miles before i turned it up IMO Quote Link to comment Share on other sites More sharing options...
iomlt Posted May 25, 2011 Share Posted May 25, 2011 I'd crank it up as its in warrenty! Quote Link to comment Share on other sites More sharing options...
Snagger Posted May 25, 2011 Share Posted May 25, 2011 Interesting, I've just fitted EGT,tacho and boost gauges with the hope to start 'playing' with a few settings. Currently I have a standard intercooler, I'm measuring about 0.9bar at the manifold and I believe the pump hasn't been played with (no black smoke except when starting) anyway the max temps I see are 650c on a long motorway hill foot to the floor. I assume the large intercooler is why your max temps are much lower than mine and rustys's. I had a bit of a google and it seems lack of oil and high temperatures kill turbos.... I can't find any mention of excessive pressure alone killing them .... Anyone of the competition guys care to answer that one? A larger intercooler will help by reducing the induction temperature more so the thermal rise of combustion is slightly offset and by working the turbo less hard as the airflow through the intercooler is less restricted. If you read up about thermodynamics, you will see that velocity, temperature and pressure are all interchangeable and convertible - they all add up to the total energy in the exhaust gas and reducing one will increase another, so high turbine pressure will be associated with high egt. It is this exhaust energy that the turbine uses to drive the compressor, but like anything else, give it to much and it will be damaged. However, the question seems to be more about whether the high boost pressure rather than exhaust pressure will damage the turbo, with a suspicion it's irrelevant. Sorry, but it's highly relevant and directly linked to egt - the higher the boost pressure demanded, the harder the turbo must work, and the energy input for the compressor is the turbine: if you want higher compressor pressures, you're going to need higher egt, and demand too much boost and the turbine will suffer. Try to remember the rest of the engine too, though - the higher the boost pressure, the greater the stresses on the pistons, head and head gasket. Even manifolds suffer the increased stresses, which is why the Discovery II TD5 warps its exhaust manifolds and shears the manifold studs while the lesser tuned and boosted Defender version rarely suffers such issues unless chipped. Quote Link to comment Share on other sites More sharing options...
cackshifter Posted May 25, 2011 Share Posted May 25, 2011 Another thing that could be considered helpful is a bit of ignition advance; that tends to lower EGTs and increase power and economy (all good) but increase NO emissions, cylinder pressures, and turbo lag(as there isn't as much energy in the exhaust). Also I'd say if you are doing more boost, use something better than Halflidlfordistretcherlube reclaimed 15/40 chip oil in it. You might get away with it pottering round, but sustained heavy use makes a difference. I tow a horse trailer, and after doing that with a couple of horses in you can feel and smell the heat from the engine and exhaust(and wafts of EP90 from below) as it's working so hard. Even the tailpipe gets pretty warm, and you can smell stuff on it drying off. Solo its a different matter altogether, the engine gets warm and that's it. The turbo is likely to be the first to notice deterioration in lubrication quality, especially at higher work rates, and when switched off, as the oil pressure dies away. Nigel Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 25, 2011 Share Posted May 25, 2011 Cheers Snagger and Cackshifter! It's quite clear I had missed a couple of things that once pointed out seem quite obvious now. I had completely omitted to think about the effect of the turbo requiring more energy to produce the extra boost, which is basic physics really. Thanks again for explaining the relationship between the different parameters. Quote Link to comment Share on other sites More sharing options...
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