Author Topic: So I just tuned the aaz pump  (Read 2089 times)

March 07, 2019, 05:30:54 pm

Spokerider

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So I just tuned the aaz pump
« on: March 07, 2019, 05:30:54 pm »

 Guys,
 I have done some basic [ to most of you ] tuning mods to an aaz. It is a stock engine, newly rebuilt, but still stock head bolts, etc......
 
 The list;

 aaz
 2" downpipe 2.5" exhaust from flex pipe back
 K&N cone air filter
 KO3 turbo
 Manual boost controller with boost set to 16 psi
 egt gauge installed
 No intercooler
 Turned the fuel screw in enough that it set the idle speed to 950. Yes, the idle speed screw is all of the way out, so no more slowing the rpms with it.
 Next, I turned in the fuel screw another 1/3 turn or so, adding another 150 rpm onto the idle speed. I get momentary black smoke when I blip the throttle.

 Took it for a test drive........ up a hill, 200m long, about a 10-12 percent grade. Full throttle.
 The samurai pulled all of the way up the hill, continuing to accelerate until I let off the throttle. Boost stayed at 16 psi up the hill. No obvious smoke seen in the mirror. egts' hit 700F at the top of the hill and of course, dropped right off when I let off the throttle.

 What do you guys think of these tuning mods and the resulting egt's?
 This [ heavy ] zuk is a DD and I will have some hwy driving to do, with a 3 mile long hill with 3-11 percent grade to climb / descend regularly.

 Am I going to roast my pistons? Drop a cup?

 
 



Reply #1March 08, 2019, 08:01:00 am

RabbitJockey

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Re: So I just tuned the aaz pump
« Reply #1 on: March 08, 2019, 08:01:00 am »
700 is pretty cold, that's a really good test you did though, i'd be shooting for a max temp of 1000-1200 on a pull like that, IDI engines are really sensitive to heat. 700 is very safe though. For other mods if i were you i'd check your boost pin, make sure it's not the flat boring one, and considering doing the governor mod. Can you take a picture of your throttle lever and post it?
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Reply #2March 08, 2019, 07:59:43 pm

Spokerider

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Re: So I just tuned the aaz pump
« Reply #2 on: March 08, 2019, 07:59:43 pm »
I forgot to mention that I did the 1.6TD boost pin swap too. It was there for the test run that I described.

 Being new to diesel pump tuning.........I have a question regarding egt's.

 Does duration of the engine load, as in a long hill, say 4 miles long effect the egt's? vs a short 200m long hill? In other words.....if the boost is constant for the duration of the engine load, and the fuel being burnt is constant for the duration of the engine load.....as in the 4 mile long hill, will egt's remain at a steady xxx temp, or will they climb because of the duration?

 So to reflect on my test run......if the egt's hit 700 F cresting the 200m long hill, could I drive the same hill if it were 4 miles long, and expect the egt's to be in the neighborhood of 700 degrees?

 

Reply #3March 09, 2019, 05:28:12 pm

libbydiesel

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Re: So I just tuned the aaz pump
« Reply #3 on: March 09, 2019, 05:28:12 pm »
Off the subject, but I'm not a fan of K&N filters.  They pass more fine particulate than other filters.  You might want to read up on them and look at some independent studies of their filtering ability and ability to flow air. 

700°F is quite low although I'd find a longer and steeper hill to check.  If your thermocouple is pre-turbine and is a fast-acting probe (like the 1/8" Micro-1000 from AircraftSpruce) then a decent max sustained EGT would be 1200°F.  The partial load boost and EGT's aren't really a good indication of what's going on.  Fuel is needed to make boost.  The K03 should certainly be making boost by 1,000 RPMs but it is hard to say if your lack of boost is simply lack of fuel or if you have some other issue going on.  Leaky wastegate is certainly a possibility.  Any other potential leaks in the intake/exhaust?  How do the fins of the compressor and turbine look?  Does it spin freely?  Can it rub the side of the compressor/turbine? 

Reply #4March 09, 2019, 06:46:27 pm

Spokerider

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Re: So I just tuned the aaz pump
« Reply #4 on: March 09, 2019, 06:46:27 pm »
Thank you for chiming in Libby.

 I know the K&N is less than spectacular, but have essentially no room for another type of short air filter in the very, very crowded zuk engine bay. It will have to do for now.

 My egt gauge and probe is GReddy. Me thinks it's decent quality. Certainly spendy enough........ Dunno how it compares to the "bench mark" spruce probe tho.

 
 Yes, I'm not sure if this Ko3 is operating properly or not. I want to determine if it is or not, before doing any further pump mods.

 Here is a list of what I've done to date, and the results;

 * The mods in my 1st post.
 *  Installed a manual boost controller, set max boost to 16 psi.
 * Turned in the fuel screw to a point where I could not lower the idle speed with the long idle speed screw. [ aaz pump, remember ].
 * Turned the fuel screw in further, so that I had to turn in the cold-start idle speed screw to be able to reduce the idle to 950. Yes, I have lost the 1250
    rpms for the cold-start idle speed to do this.
 * Installed a 1.6TD boost pin, 1.6TD LDA spring and cover with smoke screw into the aaz pump.
 * Turned "in" the smoke screw to increase idle speed by...? 50 or so, and mainly as an effort to get more boost at lower rpms. That was the reason for
    installing the weaker 1.6TD LDA spring also.....but essentially zero result with boost at lower rpm's.
 

 Today, with said mods, went for a test drive to see if the boost was coming on at lower rpms.

 Level road, 3 rd gear in the zuk, holding 1500 rpms, boost was 5 psi.
 Same stretch of level road, 4th gear, holding steady at 2500 rpms, boost was 6 -6.5 psi.
 Of course, when full throttle [ same stretch or road ] in either gear, max boost of 16 psi was reached.
 No smoke seen in the side mirror doing this drive, or on the hill tests / full throttle / max boost test yesterday either.

 Now, I know it's a zuk with an aaz and not a vw like you guys are used to, but I don't have any other "measuring stick" to try and determine IF this Ko3 is operating correctly or not.
 
 My plan is to do more egt testing as Libby has suggested, on a longer hill to determine if I'm still below 1200 F.
 If yes, then I will turn in the fuel screw more, and remove / replace the throttle lever back a notch or two to regain a 950 rpm idle speed. Repeat testing.

 Hoping someone else with an aaz and Ko3 will chime in and tell me what their boost vs rpm's is like.

 Oh yeah.....the Ko3 diaphram has a hose on the end of it......thinking it's for vacuum. No, I don't have the vacuum thingy on the aaz any longer. Would this make a difference?
 

 
« Last Edit: March 09, 2019, 06:49:54 pm by Spokerider »

Reply #5March 09, 2019, 10:12:20 pm

libbydiesel

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Re: So I just tuned the aaz pump
« Reply #5 on: March 09, 2019, 10:12:20 pm »
The extra fitting on the K03 wastegate won't cause any issue if left disconnected.  If memory serves, moving the nuts outward on the actuator rod increases the pressure of the wastegate and raises stock boost a little.  It might possibly help the wastegate seal better. 

Reply #6March 10, 2019, 11:50:47 am

Spokerider

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Re: So I just tuned the aaz pump
« Reply #6 on: March 10, 2019, 11:50:47 am »
Ok, so vacuum on the diaphram won't help. Good to cross that off the list.

 I did move the wastegate nuts to almost the end of the rod. Yes, this helps hold the flapper valve under spring tension......maybe not more tension, but maybe for a longer duration?

 Anyway, didn't notice much of a difference with doing this.

 

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