Engine Variants – Complete Overview
All common 1.8T engine variants (engine codes) with technical specifications (work in progress):
| Code | Power | Compression | ECU | Block | VVT | Lambda | Port Size | FPR | MAF | MAP | Injectors | Wrist Pins | Turbo | Intercooler |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AGU | 150 PS | 9,5:1 | M3.8.3 | 06A | NO | narrow | big | 3 bar | 70 mm | NO | 283 ccm | 20 mm | K03 | SMIC |
| ATC | 150 PS | 9,5:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 20 mm | K03 | SMIC |
| AQA | 150 PS | 9,5:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 20 mm | K03 | SMIC |
| AJQ | 180 PS | 9,5:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 20 mm | K03 | SMIC |
| ARZ | 150 PS | 9,5:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 20 mm | K03 | SMIC |
| APP | 180 PS | 9,5:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 20 mm | K03 | SMIC |
| AUM | 150 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | SMIC |
| AUQ | 180 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | SMIC |
| ARX | 150 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | SMIC |
| ARY | 180 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | SMIC |
| BVP | 163 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03 | SMIC |
| AWP | 180 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kap | 317 ccm | 19 mm | K03S | SMIC |
| BJX | 150 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | SMIC |
| BBU | 180 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | SMIC |
| AMK | 209 PS | 9:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 80 mm | 2500 kpa | 393 ccm | 20 mm | K04 | Dual SMIC |
| APY | 209 PS | 9:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 80 mm | 2500 kpa | 393 ccm | 20 mm | K04 | Dual SMIC |
| APX | 225 PS | 9:1 | ME7.5 | 06A | NO | narrow | small | 3 bar | 80 mm | 2500 kpa | 393 ccm | 20 mm | K04 | Dual SMIC |
| BAM | 225 PS | 9:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 80 mm | 2500 kpa | 393 ccm | 20 mm | K04 | Dual SMIC |
| BFV | 240 PS | 9:1 | ME7.5 | 06A | YES | wide | small | 3 bar | 80 mm | 2500 kpa | 393 ccm | 20 mm | K04 | Dual SMIC |
| AEB | 150 PS | 9,5:1 | M3.2 / M3.8.2 | 827/058 | NO | narrow | big | 4 bar | 70 mm | NO | 245 ccm | 20 mm | K03 | SMIC |
| AJL | 180 PS | 9,5:1 | M3.8.2 | 827/058 | NO | narrow | big | 4 bar | 70 mm | NO | 245 ccm | 20 mm | K03 | SMIC |
| ANB | 150 PS | 9,5:1 | ME7.5 | 827/058 | NO | narrow | small | 4 bar | 70 mm | 2500 kpa | 258 ccm | 20 mm | K03 | SMIC |
| APU | 150 PS | 9,5:1 | ME7.5 | 827/058 | NO | narrow | small | 4 bar | 70mm | 2500 kpa | 258 ccm | 20 mm | K03 | SMIC |
| AWT | 150 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 4 bar | 70 mm | 2500 kpa | 273 ccm | 19 mm | K03 | SMIC |
| AVJ | 150 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 4 bar in fuelfilter | 70 mm | 2500 kpa | 273 ccm | 19 mm | K03 | SMIC |
| BFB | 163 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 4 bar in fuelfilter | 70 mm | 2500 kpa | 273 ccm | 19 mm | K03 | SMIC |
| AMB | 170 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 4 bar in fuelfilter | 70 mm | 2500 kpa | 273 ccm | 19 mm | K03 | SMIC |
| BEX | 190 PS | 9,5:1 | ME7.5 | 06A | YES | wide | small | 4 bar in fuelfilter | 70 mm | 2500 kpa | 317 ccm | 19 mm | K03S | Dual SMIC |
Durability & Key Facts
There are many rumours about the special durability of AGU and AEB engines. In practice, however, these cannot be substantiated.
In general, all engines with stock internals are reliable up to approximately 380 Nm. Engines without VVT can handle slightly more torque due to their later torque delivery.
A general statement can also be made: the later the maximum torque occurs, the more durable the engine and the more torque can be run.
This is likely the origin of the rumour mentioned at the beginning. You often read about AGU and AEB engines with GT28 conversions and 300+ HP. Since a GT28 generally has relatively poor throttle response and these engines have no VVT – meaning torque also comes in very late – an AGU/AEB stock engine can handle 450 Nm at 5000 rpm (which, however, also applies to all other engine codes, as long as the torque comes in late).
So let it be clearly stated: maximum power is not the decisive factor for potential durability. Maximum torque and the associated engine speed are the important figures here.
Forged Crankshafts
There are also many rumours about the use of forged crankshafts. We can only provide mixed information on this: we have found cast crankshafts in engines that were supposedly forged from the factory – and vice versa.
3 bar vs. 4 bar Fuel Pressure Regulator
Another topic we would like to address is the 3 vs. 4 bar fuel pressure regulator. You often read: “Injectors have their best spray pattern at 3 bar – anything below or above is bad.”
This is not generally correct. There are injectors designed for pressures other than 3 bar, as they were explicitly built for configurations with different pressures. Furthermore, longitudinally installed 1.8T engines always run 4 bar fuel pressure. This would mean every such 1.8T has a worse spray pattern from the factory – along with all the supposedly associated disadvantages.
Pistons & Connecting Rods
Since many questions often arise about the “inner components” of these engines—especially during setup planning—we’d like to provide some information on this topic here.
In the early 1.8T K03 versions with cable-throttle (150 PS / 180 PS), Mahle 81P26++ pistons were installed as standard with a compression ratio of 9.5:1 (compression height 32.70 mm, recess depth 1.5 mm, recess diameter 70 mm) and 20 mm piston pins. These were later replaced by the 81P27, which, however, have the same specifications (9.5:1 compression ratio / 20 mm piston pins) and continued to be used in all engines with 150 PS / 180 PS, a narrowband O2 sensor, and electronic throttle. Both versions use connecting rods that, logically, also have 20 mm piston pins. In addition, these connecting rods are “sawn” at the rod end (smooth cut surface), have studs and nuts for mounting the bearing caps, and feature grooves for the notch of the connecting rod bearings.
As part of the development toward the wideband management system (150 PS / 163 PS / 180 PS / 190 PS), the pistons and connecting rods were also redesigned. Mahle 81P32 pistons were used, which still have a compression ratio of 9.5:1 (compression height 32.70 mm, recess depth 1.9 mm, recess diameter 68 mm) but feature a 19 mm piston pin. Additional distinctive features are found primarily in the connecting rods, as they now taper upward at the small connecting rod end (hence the name “trapezoidal connecting rods”). This shape is also replicated on the piston, which is why only connecting rods with a trapezoidal end fit into the 81P32 pistons. They are “cracked” at the connecting rod big end (a broken separation point, making them usable only with the corresponding connecting rod); in this variant, the bearing caps are secured with screws and have no grooves for notches.
For the K04 versions (210 PS / 225 PS / 240 PS), there is only one type of piston, regardless of narrow- or wide-band. The Mahle 81P30 piston is used here, with a compression ratio of 9:1 (compression height 32.70 mm, recess depth 2.1 mm, recess diameter 70.3 mm) and a 20 mm piston pin. The connecting rods have the same characteristics as the 20 mm design mentioned earlier.