Basic IDI vs mTDI questions

[mammonista]

Hey everybody,

1) What kind of MODERATE hp available, at what rpm, at what boost from my 1.9 AAZ engine currently in 'Van-no-mo'?  I'm shooting for 110/120hp.
2) The turbo (not sure what make/model) was rebuilt a long time ago and currently makes no more than 10 pounds at full boost (something may be stuck).  Should I plan on replacing?
3) The pump was rebuilt 5 years ago but works well. Do I need to send it somewhere for tweaking?
4) Injector/nozzles need replacing for more HP?
5) I'm currently running an air-to-air IC but plan on replacing it with a water-to-air unit with a front mounted radiator for better cooling...any concerns there?
6) Van-no-mo has an early model DK (air-cooled) trans with 15-inch tires. She runs 3,500 rpms at 68mpg returning 27/28mpg.  What changes might I expect?



I recently bought a MK1 Jetta TD coupe with 3-speed auto. A previous owner blew the turbo motor and replaced with a 1.6 NA diesel and man is this thing slow!!!! I bought a '96 AHU engine / 5-speed trans to swap in. The engine has been fitted with a Rover 300 pump and Bosio 520 injectors. Would that engine be better suited in Van-no-mo and the AAZ engine swapped into the Jetta?



ALL ANSWERS/OPINIONS WELCOMED!

[vanbcguy]

The AAZ can put out 120 HP fairly easily. The stock turbo and injectors are fine. The pump itself is OK but the LDA pin will need to be swapped over to a 1.6 one. An intercooler of some sort is essentially necessary. You'll be wanting to turn the boost up in to the high teens plus crank up the fuel.

The AHU with the Rover pump will have more potential than the AAZ. Whether you should swap or not, that's another story. You can get decent power from the AAZ without much work though the AHU will yield better fuel economy in the end.

Sent from my XT1097 using Tapatalk

[mammonista]

Thanks Bryn,
Okay ignorance here... "the LDA pin from a 1.6 pump" 1) is that something I can do myself or does it need to go to a shop? 2) source for the pin? (would a pump rebuild shop have one laying around)? 3) Is boost adjustable at the turbo? Like a screw on the wastegate or something? 4) Is boost adjustable at all rpms and throttle openings? as I remember cruising down the highway at partial throttle (3,500 rpms/65-68mpg) showed boost at about 4-5psi. Should that be higher?
Once again many thanks!!!!!!!!!!!!

[vanbcguy]

The pin is easily changed, there's 4 screws on the top of the pump you undo to get at it.

Pump shops MAY have a pin, but probably not. You'd be best off posting a want ad on the classifieds here. I sold my spare a few months back.

Boost is "sort of" adjustable at the turbo. Ideally you need to buy a manual boost controller - google "NXS Boost Controller" for a reasonably cheap option. It gets plumbed in to the boost hoses going to the wastegate.

Cruising boost with a wastegate turbo is a function of the size of the turbo combined with the load on the engine; nothing you can adjust. The harder the engine is working the higher the cruising boost will be. Nothing you're doing to increase peak power will affect cruising.

Sent from my XT1097 using Tapatalk

[mammonista]

thats an LDA pin from a 1.6 td pump? or any 1.6 pump?  is there a difference?

[RunninWild]

Non turbo pumps don't have an lda. I'm pretty sure you also want the 1.6td lda cap. The lda is adjustable on the 1.6 pumps and in*most cases* the 1.9l pumps are not adjustable.

[mammonista]

Got 'ya. Thanx evrybody. Now the search is on for the cap/pin.

[mammonista]

boy do i feel like a doofus.  first i discover that the 1.6 NA Jetta engine (that will soon be replaced with a mTDI) has a turbo injection pump (from the 1.6TD engine a PO replaced with the NA).
so I already have the LDA pin and cap for installation on the 1.9 AAZ pump.
then i popped the engine lid on 'van-no-mo' and discovered that the pump on the AAZ engine is already a 1.6 td pump!
then i remembered... a long time ago (20 years?) I bought a canadian AAZ crate engine and swapped out the 1.6td i had put in the van from a quantum. I must have used the 1.6 pump on the crate motor. 
But even though both are apparently 1.6 pumps, the LDA cap looks somewhat different. Is that an issue?  Or am I missing something here?
THIS IS THE PUMP ON THE AAZ ENGINE IN VAN-NO-MO

AND THIS IS THE PUMP IN THE JETTA

[mammonista]

Please excuse my ignorance. Do I need to change my turbo if the end goal is 120hp from my AAZ engine? And if so what's a reasonably inexpensive choice



And assuming I stick with this pump is this hooked up correctly?

[vanbcguy]

Some of the AAZ pumps are visually identical to the 1.6 pump, just FYI. The AAZ pump is a better starting point for power than the 1.6TD one but either will work. Just make sure it actually has the "good" LDA pin. Check the VW part number on the pump, if it starts with '068' then it's a 1.6 pump for sure. I think 028 is the AAZ prefix.

I'm guessing you have a K14 currently? They are a pretty decent turbo though they can't be pushed as hard as say a K24. The general consensus around here is to stick to about 18 PSI with a K14. I think 120 HP is probably achievable with that turbo on an AAZ provided you can figure out a good intercooler solution. An AWIC might be the best way to go in a Vanagon.

Yep, pump is hooked up correctly. There was originally a rubber cover on the vent to help keep junk out of it.

[mammonista]

He Bryn,
Thanks for the info. I'll be checking the numbers on the pumps.  Would I be better off just replacing the turbo? I mean the actuator housing is shot. Are those even available anymore?
What would be a good source for a new K24 (assuming those are available) and what would I expect to pay? Would the manifold mounting holes match up with the 1.6 manifold that's on the AAZ or should that be swapped out for something newer?
Mark

[RunninWild]

K24 is an old design if your going to buy something newer a vane turbo from a tdi is a good choice but you will have to figure out a way to controll the vanes. A holset he200wg seems to be the best turbo at the moment.

That turbo you have is probably a t2. The Wastegate actuator can be repaired but it's a bit of work. You would need to cut apart the diaphragm housing and remove the spring. Then you would need to find a new diaphragm actuator make some kind of mounting bracket and attach its shaft to the original someway. Definitely not the easiest job but it can be done if you have a welder and a bit of free time. There may be an easier way to attach a new oem actuator but like you said they are probably hard to find and probably expensive.

[libbydiesel]

That's a T3 from a 1.6TD Quantum or Audi.

As far as the AAZ pump is concerned, it is not just the boost pin, but rather the whole lid.  The AAZ lid would need a fair amount of precision machining to use the 1.6TD pin, metal tube, star wheel, spring, etc...  Best, IMO, would be to use the AAZ bottom and the entire 1.6TD pump top.  That way you keep the AAZ camplate and dynamic advance, but add all of the 1.6TD aneroid functionality.

[mammonista]

well that makes sense as far as the turbo goes, because I think I bought a beater quantum for the td engine, transplanted the engine into the van and then bought the current AAZ engine a few years later and put the turbo and 1.6td pump on it. 
1) so can the holset be had without breaking the bank?
2) since I apparently have two 1.6td pumps (the one currently on the AAZ engine) and the one on my MK1 Jetta (that I won't be using as soon as I do the mTDI swap) is either up to the task of fueling the AAZ engine up to its true potential? Obviously the current pump can fuel the engine as I had been using it for years without issue, but maybe I should start with the correct pump in the first place?

[RunninWild]

I believe both pumps are similar in the amount of fuel they can deliver. The main difference between the 2 is how they deliver fuel. The Aaz has a more aggressive cam to deal with dual stage injectors. This is a benefit in tuning for more performance. The 1.6td has the more aggressive boost pin which I believe let's it give more fuel earlier on with boost and less smoke off boost. I don't think you would see a major difference between 2 stock pumps. Getting a Giles built pump would be the best option.

I think the holsets go around $650 but you then also need a different exhaust manifold. You would also need to modify your exhaust to meet a custom down pipe and come up with custom oil feed and drain lines. Its not a plug and play swap by any means. It may be tricky to make fit in the engine bay depending on how much space you have.