The new Mercedes-AMG A 45 S 4Matic
The german Sport Auto car magazine conducted a traditional fast lap at Nurburgring with Mercedes-AMG A 45 S 4Matic+.The result was an impressive 7:48,8 minutes.
The new Mercedes-AMG A 45 4Matic+ features the M139 engine, the most powerful four cylinder in the world with 2.0 liter displacement, 421 HP/6,750 rpm and 500 Nm/5,000-5,250 rpm in top version S.
With a maximum charge pressure of 2.1 bar delivered by a single twin scroll turbo, the M139 engine has the highest charging pressure in its segment. Like other AMG engines is built after the “One man, one engine” principle.
It is the first 4 cylinder turbo engine in which the shaft of the compressor and turbine have roller bearings to reduce mechanical friction and to reach more quickly its maximum speed of up to 169,000 rpm.
Compared with 306 HP 2,0 liter four-cylinder installed in the 35 models the new engine is rotated around its vertical axis by 180 degrees. This means that the intake system is positioned at the front and the turbocharger and the exhaust manifold are positioned at the rear on the side of firewall. This configuration allows the ideal air ducting with shorter distances.
The engine is mated with the 8-speed AMG Speedshift DCT 8G dual-clutch transmission and the power is sent via all four wheels. The AMG Performance 4Matic+ all wheel drive features AMG Torque Control in the new rear axle differential which has two electronically controlled multidisc clutches each of which is connected to a rear axle drive shaft.
So, depending on the driving mode and situation the drive torque cand be separately distributed to both rear wheels.
The Mercedes-AMG A 45 S 4Matic+ come as standard with 19 inch wheels in a 5-twin-spoke design and a width of 8.5 inches, shod with tyres in size 245/35 R19. Sport Auto magazine has changed the standard tyres with semi-slick tyres Pirelli P-Zero Trofeo R M01.
It is well known that semi-slick tyres can save a lot of time in the Green Hell challenging track and we also have to mention that the car has no optional extras. But on the other side, these semi-slick tyres are perfectly road legal.
With semi-slick tyres, Mercedes-AMG A45 S 4Matic+ has reached the best lap with 7:48,8 minutes on the 20,6 km Nurburgring race track.
How good is this record? It depends.
In a test conducted by Sport Auto, BMW M4 has reached 7:52 minutes with a stock car in 2014.
The best time for a hot hatch was 7:40 minutes for Renault Megane RS Trophy-R With Bridgestone Potenza S007 tyres in April 2019. But this Megane is not really a stock car.
The best result for a standard hot hatch was reached by Honda Civic Type R in April 2017 with 7:43,8 minutes. And both are only FWD cars.
Another reference in the hot hatch segment is VW Golf GTI Clubsport which registered a 7:47,19 minutes in December 2016 following a test conducted by VW Group.
The time of 7:48,8 minutes could be even better. If you look the video you will see that at 7:59 there was a little gearbox failure (component protection) and the gearbox suddenly went in the N position. The estimated loss time was 0.8 seconds.