The Porsche Expansion Add-on for Forza Horizon 2 has 15 achievements worth 500 gamerscore.
Obtain your first Porsche.
Tick off 5 items on the Porsche Bucket List
Complete the Porsche Bucket List
Complete 10 events in the same Porsche.
Complete 40 events in Porsches.
Earn 25,000 Credits in Rivals Mode with the Porsche 911 GT3 RS 4.0.
Pull off 30 Near Miss Skills in the Porsche 911 Turbo S.
Win a race in the wet in a 1982 Porsche 911 Turbo 3.3.
Pull off 20 Drifts in the 2015 Porsche Cayman GTS.
Earn 20 Clean Racer Skills in the 1989 Porsche 944 Turbo.
Complete 4 events in the 1987 Porsche 959.
Complete 4 events in the 1970 Porsche 914/6.
Complete 4 events in the 2014 Porsche 918 Spyder.
Complete 4 events in the 2015 Porsche Macan Turbo.
Complete 4 events in the 2003 Porsche Carrera GT.