Midnight Club: Los Angeles

After you beat the city champ, Booke (unlocked the "Retire the Master" achievement) you have to win 35 races in a Muscle car for the muscle champ to challenge you and it must be the same car for all 35 races.

The easiest way to do this is select arcade then do the ordered race "Welcome to Hollywood" 35 times. It takes less than a minute to do the race and you can just retry it until you get challenged.

For these champs there seems to be a lot of confusion on exactly what to do to unlock them. Here is exactly what you can do in order to unlock each champ and how it works.

1. Win 35 races in the specific type of car (I.E. tuner, muscle, luxury etc..). The races do not count until after you unlock level 4 type vehicles. So once you can use luxury and exotic the counter starts for the 35 races.

2. Beat the city champ. None of the car specific champs will show up until you do.

As soon as you meet both of these conditions, the car specific champ will contact you to race. My advice for the 35 races is to do highway races over and over again. They almost always have an easy one that lasts less than a minute and the racer appears at the finish line so you can start the next one right away. If cops appear you can usually even slow down for them to pass and then speed up again to win the race. Good luck and let me know what can be done better if you have any issues with this solution!

In order to challenge each of the Vehicle Type Champions, you will need to have 35 wins in the said vehicle type after unlocking Group 4 Vehicles at around 16,500-18,000 rep (sometime after reaching Champion Rank). You will also need to become City Champ for these missions to spawn assuming you met the requirements.

You can just repeat Welcome to Hollywood or Sunset and Vine as these races would average around a minute and have an easy track layout. Just repeat it until you reach 35 wins with muscle cars (after group 4 vehicles are unlocked) and receive the call (assuming you are already City Champ).

You can also do Freeway Races, Red Light Races, Wager Races, Tournaments, Series Races or Goal Attack races to farm the required wins.

The Muscle Champ is Marcel, who drives a Chevrolet Camaro Concept, and you will face him in a one-on-one duel in a random track in the Beaches, The Camaro is a Group 3 Muscle car, so this challenge is very easy if you use a Chevrolet Corvette Z06 or Saleen S302 Extreme, the two fastest Muscle Cars in the game.