Need for Speed: Shift 2: Unleashed

In order to get this achievement,you have to buy DLC game add on from the marketplace,the name is Legends pack,it contains 11 cars, a new circuits and a career events,it costs $ 9.99 plus tax,download,and buy the cars from the lot for $ 00.00,search or create an online session that requires,legends pack,or create unranked match and invite a friend or someone who have the legends pack,win the race and the achievement is yours,you have to be in first place,being in podium doesn't count, this one is hard to get right now because a few people have the legends pack,so be patient and wait for someone to show up in your lobby,or play in the weekend and rush hours.
You have to use one of these cars to win,on any track you like.

Alfa Romeo GTA 1600
Austin Mini Cooper
BMW CSL Gr4
Ford Capri RS3100
Ford Escort Mk1
Ford GT40
Jaguar E-type
Lotus Cortina
Nissan 240ZG
Nissan Skyline 2000GT-R
Porsche 911 Carrera RSR
Porsche 914
Shelby Cobra Daytona

As far as 2019 of July me and two others (Sarcasticjoker), and (darkiling1542) figured out the solution to getting this and I think the rest of the dlc achievements.

Step 1: attempt what you are going for, if nothing pops then this solution is for you!
Step 2: after your attempt what you are going to want to do is leave the lobby, and on the menu where you select career, Xbox live, quick, car lot, etc you are going to press the Xbox home button and press X to sign out.
Step 3: once you sign out a prompt should pop up saying a change of gamer tag was changed and you will be sent back to the start main menu. Something along those lines! Just hit The A button for ok.
Step 4: when you are back on the start menu press the start button, then you select your profile.
Step 5: now you are going to go and to quick (quick race), and just pick the oval track, one opponent, one lap, use one of the speed hunters cars, doesn’t matter if you win or lose just complete it.
Step 6: now just attempt the achievement you are going for and it should unlock.

NOTE: this should work for the legends achievement too!
Also, you may have to use this method every time you start the game for the first time!