Seeking advice on engine upgrades

[harpy]

I spent a solid couple of weeks obsessing about what direction I wanted to go in for my wagon/variant build, to the point that it was keeping me up at night. I realized it would make most sense to flesh out my ideas here and seek advice from you all.

This is a long-ish post, so here's my brief abstract: Should I upgrade my 1.6 NA? Build up a TD motor? Or drop in an AAZ? I'm stuck!

So anyway, I rebuilt my 1.6 NA 9 years ago and have put around 50k miles on it. It's strong and perky but has been a little neglected since I bought my Sprinter (i've also noticed harder starts and lower top highway speeds). Since I've been putting all this time into aesthetic upgrades, I figure it's time to rethink the heart of my beast. I'd love to have a little more power and maybe increased MPGs. Also should note that I'd love to reinstall an AC system. I deleted my AC belt configuration and have been happy with the worry-free belt setup so I know what I'll be dealing with if I follow through with AC. Not a huge issue but still part of my thought process.

Anyway, here are the three options I have to work with:

★ Option 1: Upgraded 1.6 NA ★
Same motor, with head studs, Giles pump, new head gasket, etc.
- Check valve clearance and adjust shims as needed. Verify compression in all cylinders.
- I have a hydraulic block mated to a mechanical lifter head. The extra oil drain in the block was tapped/plugged but I plugged the water jacket hole in the head with JB weld.   I know. While I haven't seen any huge issues, there is some weepage. So, I was considering pulling the head and having a shop tig the hole.
- Install ARP head studs and upgraded head gasket (that's a thing right?).
- Install Giles performance IP (procured from a friend who never ended up installing it and is selling it cheap).
Associated costs: Giles IP - $500?, head studs - $200, head welding: $100? Total - ~ $1000

★ Option 2: Convert 1.6 to TD ★
Running junk yard motor upgraded with turbo setup
- Build up a secondary running motor pulled from a junk yard.
- Solid lifter ME block with a head that ends with a D, which I understand was used for the TD engines. I'll be running a compression test this weekend to see if it needs full teardown.
- I have all the components I need to do a full TD build, including a K14 turbo and a k24 turbo. I've been looking into both options and understand the risks and advantages of both running on this engine.
- I would install oil pressure/temp gauges and a pyro gauge to make sure I don't wreck an engine not meant for these pressures.
- I can buy a $75 TD IP core from someone to have rebuilt, so I would be getting the most of the TD build (boost enrichment, etc)
Associated costs: Engine/Tranny pulled and TD parts - Close to $1000 ¯\_(ツ)_/¯, Additional costs (head studs, gaskets, bigger exhaust) $1000 to ∞

★ Option 3: Swap to AAZ ★
AAZ engine shipped from Canada, mated to 020 AOP trans.
- This option was presented to me on FB when I was going through turbo ideas a while back ago. Seeing as how I had no leads on reasonably priced AAZ engines or cars, I didn't really think too hard on it. But I was connected to a guy named Andrew Moore who runs CanadianCatalyst.com and he said he had 5 running AAZ engines in his inventory. He would sell one for $1400 (with shipping). I have no reason not to trust this nice man, but if anyone else is familiar with him or his company I'd love some feedback!
- Obviously this could potentially be a no-brainer swap if I chose to go this route. Better power, better belt system, and with potentially no engine tear down or rebuild involved (fingers crossed). If it's as perfect an option as I believe it could be, then there's really not a lot more to it than dropping it in and running it. Also, since I'm interested in adding AC, I'd have a better belt system and would just need to see if the Mk2 components matched up with the Mk3 compressor.
- The only downside is a very minimal one -- I spent so much time and money researching TD builds and collecting parts that it would be a shame to just abandon that route! Or it just means I put the parts to use on a new car build
Associated costs: Shipped AAZ Engine: $1400, upgraded exhaust - ??

[libbydiesel]

You might also consider option 4:

mTDI AHU/1Z from a US Mk3 Golf/Jetta/Passat.  The installation and cost is similar to the AHU, but it gives both better performance and better fuel economy along with eliminating the pre-combustion chamber insert issue.  Mk3 parts are a lot more scarce than they used to be but more readily available than the 1.6 or 1.9 IDI stuff.  Definitely more available in the US than the AAZ engines.  If going that route, you might want to pick a Mk3 TDI manual trans also as the gearing would be better, the trans is more robust, and you could then run a full TDI clutch kit.  There is a kit available for mounting that trans into a Mk1 or Mk2. 

[ORCoaster]

Now he is going to be up even more at night questioning his options 1-3.  Way to go.  Send him some sleep aids.

[libbydiesel]

In that situation I would either choose the cheapest/easiest route to add a turbo to an already acquired 1.6 engine and enjoy it like that until it died... or I would go with the Mk3 mechanical TDI.  The Mk3 mTDI is probably the best 'bang for buck' as far as both fuel economy and performance.  At this point, I wouldn't choose an AAZ.

[SKip65]

Did you make a decision?  I'm in a very similar situation.  My 82 1.6NA is running well but I'm considering an upgrade.  I was leaning towards option 3 as it seemed like the most straightforward both in terms of the initial work and future ability to maintain.  I'm curious which way you decided to go.

[libbydiesel]

Did you make a decision?  I'm in a very similar situation.  My 82 1.6NA is running well but I'm considering an upgrade.  I was leaning towards option 3 as it seemed like the most straightforward both in terms of the initial work and future ability to maintain.  I'm curious which way you decided to go.

That's funny.  I wouldn't even have Option 3 in the list.  I would choose either Option 1 if cheap or Option 4 for best overall end result with the least effort. 

[fatmobile]

   I wouldn't chose an AAZ either.
 If you are going to have prechambers might as well have a 1.6.
 I love my 1.6 with a VNT-15 turbo. Zippy, and sounds great.
 Doesn't have the grunt of the 1.9s, AAZ or TDI
but it has some low end power because the VNT-15 supplies loads of air at low RPMs.

 1.6 engine and fuel/timing belt parts are cheap (compared to TDI).
 Pretty cheap turbo.
 You can use any intake, even from a gasser.
 Easy to build downpipe.
 Just a NA injection pump.
Cheap upgrade with great results.

[harpy]

Alright Libby, YOU WIN.



I couldn't pass this up on FB Marketplace. 98 tdi with "solid, running motor." Mechanic in North Jersey sold it to me -- it was his daily driver until rust took it over. Then he let it sit in his shop's back lot for four years (he didn't have the heart to junk it). So, it looks like I will be going AHU route with full drive-by-wire setup. Having the donor car to pull everything from is key, otherwise I'd just do mTDI.

He said it needs an alternator, so I have a bosch 120 amp coming in a few days, as well as filters. Hoping to try to start this thing up by next week just to make sure I can actually get it running in it's original form.

I'll be searching for any info on doing the swap. From what I understand, it's just going to be A LOT of work. full wiring swap, 02a fitment, instrument cluster, pedal cluster, etc etc. I haven't found a lot on this forum via search, but if anyone can point me to links I'd sure appreciate it!



ALSO, somehow I lucked into finding a VERY clean Quantum in central PA for $500. So obviously I'm buying it. Engine is dead, but I have a spare 1.6 and enough turbo components to choose from so I will 100% be going TD. But actually --- this Quantum has the diesel tach in it. Does that suggest it was originally TD? I didn't talk too much about the engine with the person, just that it's toast. So anyway, I guess I'll get the best of both worlds!

[libbydiesel]

I have a couple stock eTDI's and have no fear of wiring, but when doing a swap I have always chosen to use a properly built mechanical TDI injection pump and sell off the electronic engine management to offset the cost.  The end result is a more reliable vehicle with similar performance and fuel economy and a lot less work to make it and overall less cost.  The electronic engine management is a downside even if properly installed when compared to a properly built mTDI pump. 

[harpy]

I looked into mTDI quite a bit. The writeup on this site on choosing a pump is great. But I did a little looking and couldn't seem to find a suitable pump. And Giles would need three pumps and $1500 to make one. Soooo I'm not 100% opposed to doing this but I don't know if I have the means to cobble together a pump that would work. Do you have any leads on drop-in mTDI IPs?

I have a couple stock eTDI's and have no fear of wiring, but when doing a swap I have always chosen to use a properly built mechanical TDI injection pump and sell off the electronic engine management to offset the cost.  The end result is a more reliable vehicle with similar performance and fuel economy and a lot less work to make it and overall less cost.  The electronic engine management is a downside even if properly installed when compared to a properly built mTDI pump.

[Dennis Froelich]

See if Libby will build you a pump.

[libbydiesel]

Yes, I actually recently purchased a small lot of brand new Bosch pumps that are perfect for the VW TDI engines.  They are full aneroid pumps with the 20mm main shaft.  Long pump snout.  12mm plunger/head assembly.  Proper timing advance.  The governor allows revving over 4,000 rpms.  They are total bolt-on pumps for the ALH.  For installation on the AHU, the pump bracket would need to be machined to the larger ALH snout diameter.  Operationally they are most like the LT28 injection pumps but with the larger snout diameter of the ALH.  They have high fueling potential.  The price for one of them is $1200 shipped in the lower 48 states.  No cores required.

   

[harpy]

This is great to know! I've considered this option for a while so it's good to see there are pumps available. I'm still stuck in research mode for going full TDI though. I love the idea of having cruise control. Once I understand what needs to get done I'll be able to make an informed decision.

Is the transmission kit for mounting purposes or for hydraulic vs cable or linkage conversion?

I've yet to see a thorough write-up on a drive-by-wire AHU mk2 swap, so if anyone can point me in that direction that would be great. I'm still very new to this. I understand some of the extra components I would need:

- Passat/corrado B4 pedal cluster (or else I modify mk3 cluster?)
- instrument cluster
- possible different front frame bar/mount?
- Beefier suspension, mk3 steering knuckles
- aaaand ELECTRICAL

Until last week I never really considered this. I figured I'd just scour the wiring diagrams and dig through wires to splice what I need together. Then someone brought up something I was hardly aware of -- CE1 vs CE2. I have CE1. CE2 would be much easier. Most of the wires under the hood of my 1.6 are disconnected. No fan. No AC. My coolant temp and oil pressure sensors work, so I never bothered with the rest of the wires and relays.

Since I'm still thinking through the full TDI swap, here are my options for wiring which I've been considering:
- Stick with CE1. Outsource a harness build to someone. Would need for engine and fans, A/C, anything coming over from TDi. Splice together as needed.

- Convert to CE2. Would allow for a more "plug and play" swap. I have my MK3 I could pull from -- but I imagine I would only want the engine bay harnesses. I could strip a 1990 that I know of for everything else and put it in my car. or I could bring over the bulk of the necessary components from the 90 and splice things like tail-lights in. Would force me to go through my wires and clean everything up.

As I descend into the world of swaps, I realize how much bigger and deeper the cavern is of things I don't know about. Which to me is a challenge to be faced head on. Like I said, I want to know what I'm getting into before going the easier route!

[libbydiesel]

You probably know this, but going mTDI does not preclude cruise control.  It is still considerably less work and a more reliable end result to install mTDI with cruise than to do an eTDI install.  There was factory cruise for the Mk2 and it can all be used with an mTDI pump.  From a diesel it is all bolt-on.  The cruise from a gasser can be used also along with a custom bracket for mounting the actuator.  There are also aftermarket kits that work fine. 

[harpy]

Thanks Andrew! To me it's all one big puzzle andI'm sure I'll regret going tdi but I do have a mentor and it's all one big fun puzzle to me anyway.

Side note -- someone on the FB vwdiesel page was asking about your mtdi pump. I think I tagged you but not sure if it's you or how active you are there.