Engine Tuning Potential: Unleash Your Power

Hello,

In recent generations, the 1.9-liter EU3 "core engines" with 130, 150, and 160 factory horsepower (ASZ, ARL, BPX) have been equipped with the same pistons, connecting rods, cylinder head, fuel injectors, and other components.

Therefore, every ASZ (presumably referring to a specific type of vehicle or component) should also have factory-standard reserves up to 160 horsepower when the peripherals are modified (especially the turbocharger and intercooler, possibly also the water pump).

According to the documents, the ASZ engine is sometimes built with the same engine block as the ARL and BPX engines (038 103 101 AB), but some ASZ models have a different block; for example, my Polo has the 038 103 101 AJ block.

I once received information from all4tdi stating that the engine blocks are made from different casting materials with slightly different properties: Apparently, the ARL/BPX block is optimized for tensile strength and stability, while other blocks are optimized for low friction between piston rings and cylinder walls (if I recall correctly).

This would mean that, after extensive tuning and with corresponding driving profiles, the different engine blocks might potentially last for different lengths of time before defects occur.

Can anyone confirm this, correct it, or provide any additional information?

other blocks are more likely due to low friction forces between the piston rings and the cylinder bore (if I recall correctly).


'Shouldn't that normally affect the bushings, and not the block itself? Or does this refer to thermal expansion in cold/warm conditions?'

Therefore, the ARL/BPX block is more optimized for tensile strength and stability.

Yes, as far as I know, ARL/BPX actually uses a different casting alloy. However, I would argue that with aggressive tuning, the material of the cylinder head and, above all, the cylinder head bolts are more likely to be stressed to their breaking point.

Nebelwerfer_TDI wrote:

The material of the cylinder head and, above all, the cylinder head bolts is subjected to stress up to the bursting limit.

Cylinder head bolts maintain their preload, regardless of how high the peak pressures are. It's only when the peak pressures exceed the head clamping force provided by the bolts that the head gasket will blow. It's possible that the thinnest sections of the cylinder walls in the engine block will be overloaded before that happens. I'm quite certain that the cylinder head, head gasket, and engine block are more likely to fail than an individual cylinder head bolt.

Best regards,
Christian.

Quote:

So, I'm pretty sure that the head, head gasket, and block are more likely to fail than the individual cylinder head bolt.

That's the theory. In practice, it's the screw, believe me.
That's why I also offer pistons designed for reducing compression in the shop, so that you can control the peak pressures and ensure the engine lasts.

Best regards, Rainer.

Yes, as Rainer wrote, the same thing is happening with mine. It started at 4600 RPM and 1.45 bar, and now it's happening at 4000 RPM and 1.1 bar. I'm now waiting for the studs to be delivered. The engine block itself, however, seems unaffected.

Nebelwerfer_TDI wrote:

Shouldn't that normally affect the cylinder liners, and not the block?

Um... regarding the TDIs, I've never seen any liner sleeves in AKTE. The pistons run directly in the block.

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Yes, as far as I know, ARL/BPX actually has a different casting mixture

. Interestingly, the ASZ in the G4 platform also has the same block as the ARL/BPX.
That means installing a VB charger, converting the G4 front to an ARL-FMIC configuration (with ARL mounting brackets and cooling), installing the ARL software, and you have a "completely original" ARL.

Nebelwerfer_TDI wrote the following::
Shouldn't that normally affect the cylinder liners, and not the block?

Um... with the TDIs, I've never seen liner sleeves in the engine block . The pistons run directly in the block .

Aha - I always thought they had the bushings as a press fit?! So, cold bushings into a hot block, and as soon as the temperature evens out, they fit in very tightly. Okay, you never stop learning .

Interestingly, the ASZ in the G4 platform also has the same block as ARL/BPX.
That means installing a VB charger, converting the G4 front to an ARL-FMIC configuration (with ARL mounting brackets and cooling), installing the ARL software, and you have a 'completely original' ARL.


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And the cylinder head plus screws? The ARL/BPX screws are different as well...

Nebelwerfer_TDI wrote:

Aha - I always thought they had the bushings as a press fit?! So, cold bushings into a hot block, and as soon as the temperature evens out, they fit in very tightly.

I can't completely rule it out. But according to my information, those connectors are definitely not sold separately.

Quote:

And cylinder head + screws? The ARL/BPX screws are different too.....

The cylinder head is the same everywhere. The ARL has tighter cylinder head screws, you are right (I had forgotten).
But, according to the documents, the BPX has the same (soft) screws as the ASZ and the weaker 1.9 PDs .

As far as I know, only aluminum blocks have separate cylinder liners, while cast iron blocks do not.

I've also noticed that the ASZ and ARL engines sometimes have the same ET number for the engine block. However, I believe this is likely due to cost-saving measures and only applies to replacement parts (meaning a replacement engine block for an ASZ might have the stronger block from an ARL). I assume that in the original factory configuration, the blocks are different.

If my memory serves me correctly, AXR, ASZ, etc. are GG-25 blocks, while ARL and others are GG-27 or GG-28, meaning they are made of a casting material with higher tensile strength.

I wouldn't rule out the possibility that the 130 hp engines currently being produced also have the GG28 block, because even the 140 hp 16V TDI, which is based on the 130 hp engine, received it.
The same applies to the 2.0 8V engine.

Golfosaurus wrote:

I've also noticed that the ASZ and ARL engines sometimes have the same ET number for the engine block. However, I believe this is likely due to cost-saving measures and only applies to replacement parts (meaning a replacement engine block for an ASZ might have the stronger block from an ARL). I assume that in the original factory configuration, the blocks are different.

I find this theory rather unlikely for several reasons. Firstly, neither ASZ nor ARL have the quantity of parts required. Secondly, even with a small quantity, the ASZ is certainly much more common than the ARL. Since VW has every part imaginable, why not this block as well?

It would certainly be interesting. If someone tells me where to find the block number (which I've never looked for before), I'll tell you what the ending is for a G4 ASZ manufactured in 07/02. Then, we just need the ARL number, and we'll know!

ulf wrote:

According to the documents, the ASZ engine is sometimes built with the same engine block as the ARL and BPX engines (038 103 101 AB), but some ASZ models have a different block; for example, my Polo has the 038 103 101 AJ block.

Starting with model 03 and a specific chassis number, there is also a block with the ending number AH. However, these numbers always refer to blocks with pistons. Therefore, they unfortunately don't indicate whether the cylinder head itself has the same number.

According to my knowledge, the number should be located on the front of the engine, in the area to the left of the oil filter housing. That's where the engine code is usually found on the new 16V models. I can also check on mine if you like.

Golfosaurus wrote:

These numbers always apply to blocks with pistons.

Correct.

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Therefore, it unfortunately doesn't say anything about whether the ZKG itself has the same number.

According to my logic, it should: if entire "assortments" have the same ET number, then the individual parts should also be identical?

As I mentioned earlier, my assumption is that, nowadays (when these engines are no longer produced), it's done for cost reasons and simpler inventory management, so that both base engines are the same, even though they weren't identical in the original installation. Since all 4-cylinder TDI blocks are now made of GG28 anyway, it wouldn't be a cost factor; in fact, it would be more complicated to cast a few GG25 blocks in between to use them as spare parts.

Currently, the raw material part of the block also has the marking "1.9/2.0 DI". However, the "2.0" version definitely has the stronger block.

@Golfosaurus

The main reason gray cast iron is used is its beneficial self-lubricating property due to the high graphite content. The tensile strength of this type of casting is generally very low, which is of minor importance in the case of an engine block. GG25 is a lamellar graphite cast iron and has a tensile strength (Rm) of 250-350 N/mm² – which is very low. The next best according to DIN is GG30 with an Rm of 300-400 N/mm². What are the specifications for GG27 and GG28 according to your description? They should only have slightly higher Rm values than GG25. Is such a fine adjustment really necessary for just a few more horsepower?
Just the logistical effort involved with the low production volumes, as matthiasTDI96 already described.
As a designer myself, I can only say from experience that every company should try to minimize the variety of parts they use – especially the automotive industry (even though it often doesn't seem like it...).

For your information: The engine block of the Porsche Cayenne is made entirely of low-pressure cast aluminum (Alusil) and does not have cylinder liners!

Since I've also been thinking about the necessary modifications for converting my ASZ engine to run on ARL fuel, I've compiled a list of the most important parts. I compared the part numbers with those for the Golf 4, and they should be transferable to the A3.


PDF comparison of ASZ and ARL attached.

Best regards.


EDIT Bertil: PDF file added to the attachment.

I only read about GG25/GG28 online (I'll try to find the source again). Apparently, GG25 only has a tensile strength of 250 N/mm², and GG28 has a corresponding tensile strength of 280 N/mm².

Which Cayenne engine are you referring to? I'm only familiar with the VR6 engine from that lineup.

Here is the detailed explanation: http://www.carpassion.com/de/forum/audi/10998-a3-2-0-tdi-3.html#post200878

Unfortunately, this is not the original source, but I would also like to know where he copied it from.

Well, I also didn't know that there were aluminum engines without cylinder liners... I've done a little reading now, and it seems this technology is actually becoming more common. However, I doubt you'll find this technology in diesel engines just yet.

PS: I couldn't find a proper number on the building, and I didn't actually enter, I just took a quick look. I was hoping it would be located near the number of the Central Committee (ZK). I'll try to look for it if I have time.