The Lego Technic McLaren (set #42172) is an awesome build!  Here is a cool little overview of the set.  You can find it here along with some cool accessories like lighting kits and display cases.  We bought this for our son who is usually a big Star Wars Lego builder.  He has built a few very big kits, but the Lego McLaren P1 was just another level completely.  You can see more specific details below.  What stood out in my mind is the transmission and a real differential!

LEGO Technic McLaren P1 (Set 42172) – Key Features and Insights

Build Experience
The build time is approximately 25 hours, which includes some reworking. (Your time may obviously vary) If you think about the fun-per-hour value, it’s definitely worth it! The set offers a highly immersive experience, including constructing a transmission and a differential rear end.

Model Details

• Scale: 1:8
• Pieces: 3,893
• Dimensions 20.55 x 14.88 x 9.06 inches

  This set is recommended for adult builders and car enthusiasts seeking a challenging, realistic project.