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Engine Specific Info and Questions => IDI Engine => Topic started by: BoostedOne on July 22, 2015, 05:49:02 pm
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So a couple of questions:
1) Is there a big difference between na 1.6 injectors and AAZ injectors aside from the pop pressure? Can the 1.6 injectors just be reshimmed to the proper pop or are AAZ injectors needed?
Pump stuff:
Long story short, in an effort to get a turbo on my 1.9, I bought what was advertised as a AAZ pump.. I found it to be a 1.6TD pump, 0 480 494 082... I asked here if it would fuel a 1.9 and got one response saying yes, if you change the cam plate to a AAZ cam plate.
Well in an effort to make things easier, I figured I would just buy another AAZ pump while shopping Ebay.de for other things and just sell the 1.6 pump. So I bought another. This one is 0 460 494 277.
This IS an AAZ pump. But apparantly some German versions of the AAZ do not have LDA!!! The angles the photos were taken on the auction hid the fact that what looked like an lda was not an lda. See pics below... you remove the cover for the lda and it's empty inside.
So..
2)anyone have knowledge of this particular pump? Does it have potential? I like that it has the longer discharge nozzles so I do not have to distress the fuel lines anymore. But internally is it much if any different than the LDA version? I hate to cannibalize the 1.6 pump for the LDA but at this point if I have to, so be it..
My goal is somewhere in the 115ish or so hp using a nice front mount intercooler, PD intake, and somewhat on the fence turbo wise. I have a Callaway 8v turbo manifold redrilled to the t3 pattern and a T3 60 turbo laying around I could easily use, but that's probably a bit big. Also have a k03 from an early 1.8T.
(http://images.tapatalk-cdn.com/15/07/22/6e7a71c4b4dd6ee6b7804d34af15c47e.jpg)
(http://images.tapatalk-cdn.com/15/07/22/3d7cc5ddb9f52833ab0533e50f7aad7a.jpg)
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its an eco diesel pump. you can swap the lda from the 1.6 pump if you want.
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IIRC, eco pumps are 8mm plunger... xxx 494 xxx is a 9mm pump.
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that is an aaz eco pump tho, i'd check the part number to see if it is 8mm or 9mm
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Yeah its a 494 as mentioned so I assume that means it's a 9mm pump..
I guess I was curious if I do swap the lda over, is there any other differences internally that make it less desirable than a non eco pump? I can't seem to find a parts listing..
And what about the injector difference between the aaz and 1.6 na? I don't have the aaz injectors and my 1.6 injectors are in great shape.. if there is a performance difference I can get different injectors but trying to determine if I should just have them re-popped to the correct pressure?
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The AAZ injectors are 'two stage' - they have a small pilot injection before the main injection event, this makes them a bit quieter. They're hard to find however. The 1.6 injectors are single stage - they just let all the fuel go at once. They're pretty easy to find. There's no real power hiding in the injectors (the IDI injectors are much larger than say a TDI injector; they are capable of flowing more fuel than you could ever hope to burn). From a power perspective any of them will work fine. However the AAZ injector bodies are taller, so your injector lines aren't going to fit properly unless you have the correct length bodies. Bending is of course an option, but make sure you have a spare set in case they crack!
The entire top can be taken off the 1.6 pump and put on the 1.9 pump - that's probably what I'd do. There is a pin inside the 1.9 pump that will have to be removed (part of the governor lever rests against that pin rather than the LDA arm), there's a posting or two in the forum here.
Performance-wise, the pump base has the camplate, the advance springs and the plunger. The 1.6 probably has a more aggressive advance curve as NOx emission limits were higher in its day, you might want to swap over the advance springs. The plunger in the 1.9 pump is already a 9mm so you're good there. The AAZ camplate was the "best" one available, though this is probably a 1Y (AAZ without a turbo)... Would be worth measuring the total lift with a dial gauge. If it's around 3mm then it's a good camplate.
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Isn't the cam plate profiled differently for the two stage injectors?
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THanks a ton! Super big help.
I did distract myself away from work a little today and did some more googling. I was having not much luck searching my pumps part number, but searching for aaz and eco turned up more results. I did see references to the dual stage injectors in the AAZ as well as the height difference. I am guessing the ECO injectors are the same size?
Thats one thing I have been fighting all along with this thing, is injector lines. Currently the engine is a basket case. The 1.9 was bought as a long block, no injectors. I had my NA 1.6 pump and injectors rebuilt just before buying the engine, and for now just put them on, running the 1.9 NA. I had to bend my 1.6 lines, and after a while they cracked and started leaking. Tracked down a set of 1.9 lines, and thought I would be fine but they didnt fit well either. Thats when I learned about the difference in the discharge valves :( I got the lines with that ECO pump, so I may just track down a set of injectors.
I cant wait to get home from work today, I will check the plunger lift. Hopefully its about 3mm as you say. Thinks for the info about the advance springs.
Since the cold start lever setup on this 1.9 pump is totally different than my 1.6TD pump, I assume I would transfer over the cold start mechanism as well, since the 1.9 one has an arm that goes up to my LDA-less housing? Any idea what is up in the cover housing for the cold start lever?
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I'm not 100% sure but I believe the lower gear adjusts the timing and the upper gear adjusts the idle speed.
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The camplate profile is definitely different on the AAZ but the same cam plate gets used in performance 1.6 pumps so it'll work fine.
Hadn't thought about the different idle setups. You'll have to transfer the governor springs and throttle linkage over that go with the pump lid - the pumps with the rod on the side to the cold start have a different idle control setup with a separate idle spring and don't have an idle spring on their actual governor linkage. That's actually a downgrade, the later style is better as it bumps the idle speed up for cold starts.
You should be able to leave the cold start itself as is and just remove the rod.
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I will say if i have to go back to the early cold start stuff, I am fine with that. I live in central Florida where worst case it's about 30 degrees F when I go out to it at 530 am to start it. It never fails to fire off in the first few cranks. If I use the cold start cable it's just to make it run a bit smoother. My concern was some internal difference that would keep it from working at all if I transferred all the early stuff to the late pump.
So.. how close to 3mm of stroke should the "good" cam plate provide?
https://vimeo.com/134359659 (https://vimeo.com/134359659)
I checked several times and got 2.55mm. The 1.6TD pump was at about 2.1 or 2.2mm..
I did order some AAZ 2 stage injectors. So I will go that route. Tired of replacing injector lines and smelling diesel fuel 10-15k miles later.. which is pretty often as much as I drive this...
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FWIW, my USA eco camplate is 2.55mm. Plunger is 8mm.
Maybe u got a frankenpump.
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I suppose anything is possible. I haven't yet been able to find a list of cam plates and their lifts. I have the numbers written down at work, I think the cam plate I have ends in 377.
I did find where the aaz plate is 3.1mm. I even seen where there's ones that go to 3.5, you can do 10mm heads from the ALH, etc. It's enough to give me a headache.
Haven't found where to buy an AAZ cam plate but do have the part number.
I am trying to balance what is needed and what's the best route to go in order to be at 120 to 140hp. I mean, would the smaller cam plate combined with a 10mm head actually be better than an aggressive cam on the 9mm head? Or is the 9mm head and 2.5mm cam just fine as is?
I dunno. And is timing one of those 10mm pumps complicated.. I only go so far in a day haha..
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for those goals any vw camplate could achieve them.
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Thanks!
Please help me understand the advantage of the more aggressive cam then?
I mean, if 2.1 on a 9mm head will get to 140hp, why did VW fit the 75hp aaz with a 3.1?
And any clue as to where I would set my pump timing on this thing if I stayed with the 2.55mm plate? Would it be the same as the aaz if I am using the long delivery valves and 2 stage injectors?
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EGT and fuel would be the benefit to the more aggressive cam plate. You should probably time it to what works, I would start with what most of the pump was built with.
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Thanks!
Please help me understand the advantage of the more aggressive cam then?
And any clue as to where I would set my pump timing on this thing if I stayed with the 2.55mm plate? Would it be the same as the aaz if I am using the long delivery valves and 2 stage injectors?
Generally, for a given plunger diameter, a taller camplate makes a longer stroke and thus can deliver more fuel.
The devil is in the details though: starting when, and for how long... That's a combination of camplate slope, timing, injector pop pressure and control collar.
e.g.
The MF engine (US turbo):
9mm IP
2.19 camplate
135 * 155 bar injectors
1mm timing
boost enrichment
The 1V engine (US eco):
8mm IP
2.55 camplate
155 bar injectors
1mm timing
no boost enrichment
(https://lh3.googleusercontent.com/-Rt-IMDOsseI/UWIm-wyfsEI/AAAAAAAABJc/J5zEaT_n3rM/s800-Ic42/g5522.png)
So, while the US eco has a longer stroke, it also has a smaller diameter, so fuel load is about the same... the cam slope is steeper to compensate and not let the injection lag deliver fuel faster. *
But the eco also has no boost enrichment, so the fuel load on-boost is comparatively less due to the control collar opening earlier.
The result: higher combustion temperatures, less soot and more NOx, so a catalytic convertor was added.
Corrected
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MF and 1V injectors were both 155 bar.
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Corrected.
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I won't lie. I am so confused and trying to process all of this.
Let me see if I can try to put this together..
So even though the smaller cam plate can deliver the same amount of total fuel as the larger cam plate by adjustment of the fuel screw, the difference is the larger cam plate will shoot the fuel in much faster. This decrease in total injection time will allow more time for the fuel to burn, and that's what leads to a decrease in chamber and exhaust temperature?
Thanks for all the help in attempting to get me up to speed. And I hope I do not come across as someone who is just sitting here asking questions and wanting others to figure it all out for me. Every response has me looking up more information I am just trying to make heads or tails of it all.
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Also, did you make that graph or pull it from somewhere else?
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The cam height determines stroke, a longer stroke can deliver more fuel.
A steeper slope will deliver fuel faster for a given rpm.
I made the graph. DIY tips here: http://www.vwdiesel.net/forum/index.php/topic,33196.msg309999/topicseen.html#msg309999
Related visuals: http://www.vwdiesel.net/forum/index.php/topic,34311.msg324919/topicseen.html#msg324919
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Good reading:
BOSCH Diesel-engine management 2nd edition.
ISBN 0-7680-0509-4
Google search for "BoschDistPump.pdf" gets some interesting hits.
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Cool thanks for the links. I will check them out more in depth when I go back in the house this evening.
I get the longer stroke obviously allows for more injected fuel, but am I on the right track with what I said above in the last message? Because on one hand in this thread I am told even the 2.1mm cam can provide the fuel I need with the tradeoffs being the additional heat which obviously is not wanted.
I will likely order a copy of the book, thanks for that info as well!
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You can probably get all the fuel you want. There are caveats.
It seems VW and Bosch were playing with injection duration by using the 2-stage injectors and higher pop pressures, trying to balance increased fuel quantity with combustion quality.
If it were as simple as just dumping more fuel, it would be a cakewalk, but clatter adds stress and heat. And even with 2-stage injectors and/or higher break pressures to extend the injection duration, the fact remains that more power requires more combustion that generates more heat.
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You can probably get all the fuel you want. There are caveats.
It seems VW and Bosch were playing with injection duration by using the 2-stage injectors and higher pop pressures, trying to balance increased fuel quantity with combustion quality.
If it were as simple as just dumping more fuel, it would be a cakewalk, but clatter adds stress and heat. And even with 2-stage injectors and/or higher break pressures to extend the injection duration, the fact remains that more power requires more combustion that generates more heat.
I always wondered what of the changes vw made as time went on was related to performance, if any, and what was for emissions?
My inclination is always to go with the latest (best?) iteration of a thing like this, but I was never convinced the dual stage injectors and such
were actually an enthusiasts definition of "better".
One of these days I want to build or buy a pump for my NA 1.9L that is basically a 1Y code motor, they apparently did not use
two stage injectors at all in those throughout it's lifetime even though they were available and used in some other motors,
begging the question, why?
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Emissions are definitely a factor. As mentioned earlier any of the cam plates you've got your hands on should work fine, I wouldn't go out looking for an AAZ one until you're at the limits of what you have.
The dual stage injectors are largely for noise reduction. The pilot spray gets the burn going so pressure doesn't rise as sharply when the main spray happens. I believe there's an emissions component to that too, wouldn't surprise me that it reduces the particulate and unburned hydrocarbon levels. Absolutely everything in the passenger diesel market uses multiple injection events these days; it started with the 2 stage mechanical injectors and has continued through to modern common rail stuff where there can be several injection events happening for noise, performance and emissions reasons. Anyhow I don't think you'll see any real performance difference in terms of raw horsepower but a camplate with the right shape to run dual stage injectors and the dual stage injectors themselves will yield a quieter running engine, which isn't really a bad thing.
I think the questions are great personally. This is "advanced diesel combustion theory" at this point.
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Thanks for the help in figuring this out guys!
I hadn't abandoned this. In fact I have done just the opposite. I tracked down a copy of the Bosch Diesel Management book and ordered that, as well as ordered a pump rebuild video off eBay.
I was out of town all week for a work event which prevented me from reviewing any of the material.
I did buy some two stage injectors. Not for the stated benefits, but I can say with a 1.9 currently running on short delivery valves and single stage injectors I am fed up with leaky injector pipes. The seller I bought the injectors from only had 3 though, so if anyone has a 4th 028130201B injector they will part with, please let me know.
OK I will settle for the cam plate I have now. I can aways upgrade it later.
My plan is to make the time to go through these pumps and combine them into one, and do the governor mod. Get the injectors cleaned and popped at my local shop, and get them on the engine.
Do the delivery valves get pop tested as well? I saw they have shims in there.
Then I will start building the turbo stuff.
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