EGR mod on d40

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It would be interesting to know if any dyno tests have been done pre & post EGR mod on a stock D40 & the results.

I know that one or some of the chip companies supply the blanking plates but for what purpose? Obviously a dyno test post chip is irrelevant.
 
Mick, when your throttle is open fully, the EGR valve closes anyway so there's no difference between a blocked EGR or not at that sort of throttle position.

The EGR pipe only has soot in it that builds up over time - it shouldn't be responsible for a lot of smoke. Even if it falls out of the EGR pipe it's going into the exhaust and should appear as a puff at most.

If you want more air, how about a bigger turbo? Also, have you fitted a catch can? If not, do so, then clean out your intercooler which should have a fair bit of engine oil in it (from the blow-by). Your performance will improve a bit more and particularly, your top-end will breathe a lot better.

Tony....do you have a catch can fitted? If so would you mind taking a few pics of the installation and giving a bit of detail about the make etc.
 
I'd be willing to put my car on the dyno for this test.

It would be good to have access to a dyno for a day.

A car club I am in does it once or twice a year but it is so far from home I have never bothered.

I believe you get to do a few runs throughout the day. That would give the opportunity to do a before & after.
 
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Tony....do you have a catch can fitted? If so would you mind taking a few pics of the installation and giving a bit of detail about the make etc.

I have one - a Calibre unit - it's not fitted yet, I'm modifying the inside so that it doesn't just let everything straight back out. I also have to buy some hosing to attach it - I'm mounting mine in front of the radiator, not in the engine bay.
 
What I'd like to know is how EGR blocking affects flow of air to the turbo. I'm told it increases boost by a bit at part throttle. Also could this in any way cause the turbo to surge?
 
The EGR pipe bypasses the turbocharger air itself - the pipe physically runs around from the exhaust straight around the front of the engine and into the EGR valve that is located on the inlet manifold. It's not directly involved with the turbocharger at all.

EGR is responsible for dampening the combustion temperature. At higher combustion temperatures, nitrogen oxides (NOx) are produced and these emissions can cause climate change. The CAT is also designed to reduce NOx. EGR only operates between idle and full throttle - the valve is closed at idle and full throttle, so there's no EGR at those points anyway.

By removing the EGR, combustion temperatures across the entire middle range increase. The hotter the combustion, the more energy in the exhaust - hot air expands, requires more volume, and as a result you get more power AND more pressure in the exhaust, which is directly responsible for driving the turbocharger - so that's why blocking the EGR affects the turbocharger performance.

Surging turbos in D40s (particularly the Thai builds of late 2010) were caused by faulty turbo vane actuators (the round thing that sits on top with a vacuum hose attached to it). In other models, failures of the vacuum tubing have been responsible. In D22s, surging is often caused by the neutral position switch in the gearbox!
 
Hi,

I've recently bought a r51 pathfinder so near identical to the d40. Looking at this EGR Mod I was going to do the same thing on my zd30 Nav before I sold it. Blocking both sides is best? I know what I'm looking at and neither of the sides look difficult just intake side slightly more congested to work in. just wondering what are the 2 rubber lines in the middle of the EGR pipe and what will happen to them if both sides are blocked? I haven't taken the plastic engine cover off to actually track them, just looking for the easy answer of "don't worry about them" :p
 
The two rubber hoses lead to the radiator. The thicker section that they plug in to on the EGR pipe is a cooler - designed to cool down the EGR.

I don't think blocking both sides is necessary. If you block the end of a straw and blow into it, you don't make a lot of progress. Blocking both ends doesn't give you any more benefit.
 
ok tony so just block the exhaust side - drivers side? I was just wondering with the intake side and the turbo if you block the intake side there is less volume of air in the pipe so better spool and also less area for your cooling pipes to try and circulate etc - please no1 disect this into some ridiculous 7hour post. I'm not a mechanic, and I know F all about this EGR just understand the basic concept and to me it could make sense blocking both might have additional gain. a simple answer is still much appreciated:cheers!:
 
Like the straw, if you block one end of the pipe there will be no more flow through the pipe. Driver's side is really easy to get to so block it & relax. BTW, because there's no flow of exhaust in that pipe, the heat won't be as high in there either.
 
ah ok. makes sense now those hoses are just venturi driven. the turbo wont try and pull from that pipe will it? guessing not if your saying just block 1 side. not a drama thanks very much. I was worried a bit about higher gas temps, reading people watching the EGT's installing gauges and stuff overboosting etc but more people seem to not worry than the few that do worry.
 
The turbo won't draw from that pipe either for the same reason. The exhaust coming out of the manifold is pressurised anyway, the turbo doesn't draw from that side it's pushed by that side - hope I've explained that clearly enough.

Gas temps will definitely be higher. Part and parcel of the whole removal of EGR - EGR dampens combustion = lower temps. You remove the EGR = temps go up.

Higher temps = more expansion of the gas = more turbo power (faster spooling).
 
yeah tony thanks explained perfectly short and sweet. be getting a plate made up asap. from that perspective I've got a bit of zincalum plate laying around would that be alright to use? or should go stainless?
 
yeah that was my thought with it. it was an offcut a mate gave me after I asked for stainless... lol thanks anyways i'll get on to mine asap I've heard it shuts down so much smoother - that's my main want, I dont blow smoke not that I've seen anyway.
 
hmm it may have been due to the fact I was on night shift but this whole time I've spoken about the right side of the car and the exhaust side of the egr... polar opposites.... I will only be blocking the right side of the car injector side (right next to the oil dipstick!! not exhaust side. just wanted to clarify so I didn't look like a spaz.... :) getting some material for the plate 2day. how I enjoy days off
 
Got my Egr laser cut plate from jjohn today put in takes 5 minutes. Put it on drivers side. Works a treat no more turbo lag, very direct power.
 
Thanks for that Tony. BTW you can add "collapsing rubber intake hose" to the list of turbo failure causes in Thai built D40s. Mine's on its way out, and before this thought the EGR block might've had something to do with it.
 
Thanks for that Tony. BTW you can add "collapsing rubber intake hose" to the list of turbo failure causes in Thai built D40s. Mine's on its way out, and before this thought the EGR block might've had something to do with it.

I'd heard that. The engine bay is a really hot place and was a little concerned about mine at Christmas when we went here:

09-RockandRoll.jpg


Thankfully we didn't have any drama.

However, I am (eventually) going to replace ALL of my turbocharger hosing with metal tube and cored silicone tube for joiners. Not sure about replacing the intake hose but that wouldn't hurt to do. Was a few times on the Ernest Giles Road when full throttle was called for because of the soft sand and that intake might benefit from being a little more solid, even on the Spanish versions.
 

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