What Are The Differences Between The 150, 180, 210 And 225 Bhp Vag 1.8 Turbo Engines?" All the engines are basically the same but there are some important differences to account for their varying outputs.
For the Octavia alone, there actually seem to be three types of the 150 bhp engine. The AGU engine is the 1.8T engine in the pre-facelift Octavia Elegance/L&K FWD. This engine utilises Borg-Warner's K03 turbo, has smaller injectors to that in the facelifted cars and does not feature variable valve timing and drive-by-wire (it has an old-fashioned throttle cable instead). When tuned, this engine will not produce as much power as the later engines. 193 bhp seems to be the maximum.
The 150 bhp engines in the 4x4 (code ARX) and the post-facelift FWD Elegance/L&K (code AUM) seem to have basically the same inner workings as the 180 bhp engine in the RS (code AUQ). They all have bigger-sized injectors and feature the K03sport turbo. This is a hybrid turbo, using the K04 turbine in a K03 casing. The differences in power between all three engines seem to be merely ECU mapping related. Hence, these engines will produce similar gains when tuned. This is in the region of 205-225bhp.
The 210 and 225 bhp engines as found in the Seat Leon Cupra R, Audi S3 and Audi TT have different internals and a bigger k04 series turbo, all which allow it to produce more power. A chipped version of these engines can reach 260-270 bhp.
Below is a brief overview of various 1.8T engines. This is not a comprehensive overview, but it will show the differences between the main engines used by Skoda and the other VAG brands.
AGU
Skoda Octavia 1.8T FWD (Elegance, L&K), 10/96-8/00
Also found in: Audi A3 1.8T and Volkswagen Golf GTI (earlier models)
Output: 150 hp
Drive: FWD
Emission: Non-VVT, EU3
Throttle: cable
Injectors: small
Turbo: K03
Gearbox: EVS, EGY
AUM
Skoda Octavia 1.8T FWD (Elegance, L&K), 8/00-now
Also found in: Volkswagen Bora 1.8T and Volkswagen Golf GTI (updated models)
Output: 150 hp
Drive: FWD
Emission: VVT, EU4
Throttle: drive-by-wire
Injectors: big
Turbo: K03sport
Gearbox: EBN, ENJ, ESV, FDC
AUQ
Skoda Octavia RS, 8/00-now
Also found in: Seat Leon 20VT Topsport
Output: 180 hp
Drive: FWD
Emission: VVT, EU4
Throttle: drive-by-wire
Injectors: big
Turbo: K03sport
Gearbox: EHA (Octavia RS, 5-speed, long gearing - Leon has 6-speed 'box!)
ARX
Skoda Octavia 1.8T 4x4 Elegance, 8/00-now
Output: 150 hp
Drive: Haldex 4WD
Emission: VVT, EU3
Throttle: drive-by-wire
Injectors: big
Turbo: K03sport
Gearbox: FEX (5-speed, short gearing)
Other 1.8Ts
APX: Audi TT, 225 hp, Haldex 4WD, K04, 6-speed
APY: Audi S3 (earlier model), Seat Leon Cupra R (earlier model), 210 hp, Haldex 4WD, K04, 6-speed
ARY: Seat Leon 20VT Cupra 4, 180 hp, Haldex 4WD, K03sport, 6-speed
ARZ: Volkswagen Golf GTI, 150 hp, FWD, K03sport, 5-speed
AWT: Audi A4 1.8T/1.8T quattro and Volkswagen Passat 1.8T, 150 hp, FWD or Torsen 4WD, K03, 5-speed
AWU: Volkswagen New Beetle 1.8T, 150 hp, FWD, K03, 5-speed
BAM: Audi S3/TT (updated models), Seat Leon Cupra R (updated model), 225 hp, Haldex 4WD (S3/TT) or FWD (Cupra R), K04, 6-speed
BFB: Audi A4 1.8T/1.8T quattro (updated model), 163 hp, FWD or Torsen 4WD, K03sport, 5-speed
