3.0 litre EGR/Butterfly/Swirl Mod

[tweak'e]

had a look at the pic, you don't have the egr butterfly setup. no solenoid and you have single actuator instead of the dual.
no need to do butterfly mod as Nissan did it for you.

you have the shutdown solenoid/actuator and the swirl valve.

 

[TerranoZD30]

Thank's man for take the time to looking at!
I keep the swirl selenoid unplug for some days and notice a lill best response on low rev!

If you know some more easy mod for the zd30 I'll be happy to know hehe

Mine now have 397.800 kms and just notice some lost of power climbing.

 

[Solanum1]

Been following this thread for some time. I'm still unsure on a few things.

I've got an 02' DX ZD30 with 280 thou on the clock, has done 100,000 in the last 3 years.
I approached someone regarding the EGR blank a few years ago and was told not to touch it - let things be the way they intended it. However I'm now looking to gain a little bit more oomf... expecially when towing.

A mechanic I spoke to here in Cairns the other week suggested the EGR block is a good thing - ONLY if the engine is clean of soot to begin with. If the engine was badly gunked up, the EGR blank would achieve bugger all. He then said it would be wise to start putting money aside for potentially a new turbo as it's rare to get ZD30's over 350,000km etc. I am very meticulous with oil changes... every 5000km on the dot... Mobil Delvac 15W/40, new filters all the time.

So, I'm now keen on doing the EGR block... but as I've read through all 55 pages on this thread, I'm still not convinced on the butterfly/swirl mod. Will my engine really run cleaner with it? Will my turbo still operate properly, and run cleaner - even with the amount of K's on the clock?

 

[tweak'e]

blocking egr is about stopping the intake from clogging up which cause numerous issues.
it will make the turbo work a bit more. tho if turbo is going to fail it will fail with or without egr. its not going to make much difference to life span.
the engine will use more air so watch the air filters.

there is a school of thought that the egr helps with combustion, especially with worn injection pumps and injectors. there has been the odd person who has said there engine went worse after egr was blocked. i suspect they had issues that the egr was covering up. but unfortunately they never diagnosed what it was.

what you can do that will certainly help the turbo, is to do the egr butterfly mod.
that also reduces the amount of egr but does not block it off entirely. all it does is disable the intake butterfly. the butterfly, just like petrol engines, causes a wave reflection back to the turbo and causing sudden slow down. so getting rid of that will extend the turbo life.

i would not do the swirl mod with egr still working.

 

[Solanum1]

Cheers for that!

Butterfly mod and swirl mod are the same thing though, rght? (All 55 pages have got me confused now!)

I also read a lot have done the butterfly mod and the vac hoses have cracked... ia it available at supercrap and autobahhhhn as vacuum hoseor under a diff name?

 

[Solanum1]

Could those that have done the mods and found that it has made the vehicle worse possibly have done the mods with the vehicle badly choked up with soot and buildup to begin with? Sounds likely to me? Makes a heck of a lot of sense to do the mods only after things are as clean as a whistle...

 

[tweak'e]

Cheers for that!

Butterfly mod and swirl mod are the same thing though, rght? (All 55 pages have got me confused now!)

I also read a lot have done the butterfly mod and the vac hoses have cracked... ia it available at supercrap and autobahhhhn as vacuum hoseor under a diff name?

no. egr butterfly mod and swirl are two different things.

egr butterfly is the big butterfly in the main intake tube. it also doubles as the shut off butterfly. it partly closes to restrict air flow to be able to increase egr flow. at engine shut off it closes fully to provide smooth shut down.
if you check out a few posts above where someone from overseas has a navara that doesn't have the egr butterfly part. ie its something that nissan actually do make for certain markets.

the swirl valve is on the 2nd half of the manifold. it blocks off half the ports so each cylinder only has one port working. that reduces air flow to increase egr but also mixes egr flow. it only works in the low rpm.

hoses are standard vac hose available anywhere good autoparts are sold.

 

[tweak'e]

Could those that have done the mods and found that it has made the vehicle worse possibly have done the mods with the vehicle badly choked up with soot and buildup to begin with? Sounds likely to me? Makes a heck of a lot of sense to do the mods only after things are as clean as a whistle...

possible but i doubt it a bit.
if the intake runners are clogged up then blocking egr should make a lot of difference in a good way. with blocked up ports it would be starving for air and over fueling. reducing egr would increase the air and fix the over fueling.

i'm picking they had other issues.
possibly turbo or intake issues. blocking egr means you use more air so your more reliant on turbo performance and air intake performance.
one thought is that manufactures under size the turbo to take into account of egr flow. make it more efficient at cruise rpm with egr on, which makes it less efficient at full noise when egr is off.
with egr blocked it might push the turbo into the less efficient area on the turbo map.

the other theory is the heat from the egr helps with the fuel ignition. hot intake temps tends to advance combustion timing. so blocking egr may have the effect of retarding the combustion.
the injection pumps on these do tend to run retarded injection timing when they get worn. the heat from egr may help to lessen the effects of that.

 

[Solanum1]

Thanks for your time tweake... appreciate it!

I've got the blanking plate ready to bolt on tomorrow. I've also managed to find those very useful stock/modified plumbing pictures on the other Superthread for butterfly mod... I'll be sure to give it a go tomorrow and shall report back on any findings.

Cheers!

 

[Solanum1]

Did the blank mod earlier this week. Have not noticed any real difference as of yet... I'll give it a few weeks.

My only thought of concern though is I've put the blanking plate in the spot everyone else is putting it, however I've just replaced the injector pump to which I keep reading dies because of heat & vibration (most probably the main cause over a period of time). My concern is that where I've put the blanking plate will cause a large heat build-up (EG'temps) and warm up that pipe substantially more than normal... could this be true? (can't say I remembered anyone mentioning this yet). Have not done the butterfly mod yet... see how this all goes first

 

[tweak'e]

blocking the egr should reduce the temps and whatever temp that pipe gets its not going to effect the injection pump.
pump electronics fail due to engine vibrations and its own heat. it uses the diesel to cool the injection pump. one reason why you should not run the tank low on fuel.

butterfly mod is probably more important than blocking egr. its also the easiest to do.

 

[Solanum1]

Little bit of feedback from the EGR mod...

Have noticed a little bit more power down low. Car seems to be a bit more settled as well as the shutdowns are bit nicer. Turn the key off and the car doesnt seem to shutter as much.

Fuel economy... probably a bit better, havnt run it on a complete full tank yet and I'd say I'll know the difference from there.

Anyone wanting to do the EGR block gets a thumbs up from me... butterfly mod being done this weekend

 

[Rick Glimmer]

Hi All,
This was a fascinating thread to read.
I am happy to find this as now i have a viable solution for my problem.
The EGR tube that runs behind the engine broke at the exhaust side. I first planned to replace it, but found out they are hard to get here in Thailand.
Second option was to repair the tube but i can not find anyone that is able to do that for me. I have an oxy/acetylene set but i am not experienced enough to fix such thin walled pipe. I'll bet i just blow more holes.

Now that i read all this about blocking the whole port i will have to do it by blocking both sides where normally the pipe is connected. I see that most if not all block it at the easy spot on top of the inlet manifold, but as i have already removed this pipe i have two ports open anyway that needs to be closed.
The plan now is to cut of the pipe and use the flanges as a clamp for the pieces of metal to block the ports. I plan to use some Cor-ten (weathering steel) from some sea container material i have. This is about 1.6 mm thick.

The question i have is if it is a good way to do this? Or should i also install a blocking plate at position 1 (as shown in the pictures on this thread)?

 

[tweak'e]

Now that i read all this about blocking the whole port i will have to do it by blocking both sides where normally the pipe is connected.........

The question i have is if it is a good way to do this? Or should i also install a blocking plate at position 1 (as shown in the pictures on this thread)?

you need to block it at both ends. one at the exhaust manifold. the other one can be at the other end of egr or at the inlet manifold, its won't matter which.
i think i cut the end off the egr tube and bolted that back in place as it helps hold the valve.

 

[Rick Glimmer]

you need to block it at both ends. one at the exhaust manifold. the other one can be at the other end of egr or at the inlet manifold, its won't matter which.
i think i cut the end off the egr tube and bolted that back in place as it helps hold the valve.

I blocked it at both ends, and the engine is running better then ever.

Who knew that searching for a replacement for the EGR pipe resulted in just leaving it out.

I will have to read the thread again about the Buterfly/Swirl mod as mine has only two solenoids.

Thanks again for publishing this as otherwise i would have spends way to much money on something that is detrimental to the engines performance and life expectancy.

 

[tweak'e]

I will have to read the thread again about the Buterfly/Swirl mod as mine has only two solenoids.

no need for butterfly mod then. counties that have low emission standards didn't get the egr butterfly setup.

 

[Rick Glimmer]

Thanks again tweak'e!

 

[Rainwulf]

Gonna bring this thread back to life - just got a second hand Nav. 2004 Black D22.

Just did the egr blanking plate mod using a lump of galvanised steel, and also disabled the swirl valve with a ball bearing in the pipe. It also came with the catch can.

Today i had the main muffer cut out, so its just straight from cat, through resonator, and out the back.

So yea, thanks to this thread, it took me about an hour to do the EGR mod and swirl disable. The beasty runs a lot better now.

Next up - find out what intake mods are available, and also price a 3 inch exhaust direct back from the cat.

 

[bods]

Sounds good, although personally I wouldn't bother with a cat back exhaust on a turbo diesel. The factory dump pipe is the biggest restriction and you can get a full replacement system with a cat in it if you wish.

 

[Rainwulf]

Still saving for that im afraid. The other option is to just pull the stock dump pipe off and somehow clear out the catalyst material inside.