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Whats up everyone,

I did a couple autocross days with my 45 this summer and wanted to share some of the experience. Now I don't have a big motorsports background and didn't know what autocross even was until I got my 45, so also trying to create some awareness for people who might be in a similar situation (thanks to my bro for the tip-off). So first off, what is autocross?

Autocross (or autox) is a short course laid out (usually in a large parking lot or on a runway) with cones. The course is meant to be technical and agile, with a 'run' time of about a minute or so. A typical day usually has a morning and afternoon session, with about 3-4 runs per session.. giving a total of 6-8 runs for the day. Agility over speed on the course, so you're usually in low gears (2nd gear mostly and not getting past 3rd for the GLA). Cars are separated enough that theres minimal to no chance of collision, and whacking a cone or two is nothing near the fear of hitting a run-off, or worse, on the track.. so long story short, auto cross is a perfect middle grounds between pushing your car on the street and truly tracking it, to seeing how it can actually perform when wound-up a little bit. Plus, it's **** cheap compared to a track day, and really only have to worry about chewing some tires for wear and tear.

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The Sports Car Club of America (SCCA) is known for running autocross events, and your local region probably already does them.. I encourage looking into it if you have even the slightest of interest.

Now onto the 45...

My car has the AMG dynamic plus package, so ran RACE mode in Manual (full paddle shifts) with Sport Handling was used for the runs. The car performed flawlessly and the only thing holding it back was my inexperience. Hoping to get some GoPro footage next event, so stay tuned!

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Congrats. It's great seeing someone getting out there to practice their skills.
 

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Love seeing these kind of posts from fellow AMG owners! Nice photos too. With any performance car you really need a closed course to scratch the potential. What kind of tires are you running?
 

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Not only the type of tire, by but also the pressures.

Tips ... Bring a folding chair, sun umbrella, hat for when you're helping on the course, tire pump and pressure gauge, a bag or box to store everything that you brought in the car (that needs to be emptied before you drive the course), cooler with lots of water and drinks, food to keep you invigorated, and a good night of sleep before you go.

For first timers helmets are often available but verify. Driving shoes and gloves are not mandatory (no need to spend money ... Just go and enjoy for now). Arrange for an instructor to ride along with you. Get in the car with that instructor ahead of time to verify seating position and controls as well as strategies. This conversation starts with driving mode (comfort, sport, race). Then manual or auto shifting (hint ... auto, you'll have enough things to occupy your mind without needing to shift on top of that). Which lines to focus on come after that. Walk the course to decide where to accelerate, where to brake, where to aim, where to focus your eyes, etc. Realize you have a simple race start option by pressing the brake pedal and then rolling on the throttle before side stepping the brake.

And there's a lot more!!!!!
 

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Discussion Starter #6
Thanks guys!

@Steiner I’m on the MO Conti’s. Actually in the process of getting new daily wheels, so wanted to chew through these tires as they were still pretty new when I did the first event. Long term plan is to sell the OEM 20’s and get a set of 19’s as the autox set, probably on PS4s. Here’s what the Conti’s looked like after the first event:
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@Wayne thanks for adding all the tips!! Definitely sounds like you’ve been to an autox event or two before.
 

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This is awesome. I have an SCCA track only 20 min away from me. Will have to check out their schedule. Looks like a blast.
 

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Those are good times, out there
+1 on sunscreen
volunteer to do tech inspection, or timing setup, it keeps you out of the sun retrieving cones
when they tell you to keep your eyes up, its true. just very hard to do when the red mist decends. hehe
Get some Blue tape for your # Blue is faster
 

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wow on those tires!

I heard Potenza RE-71R's were autocross cheater tires.... so I bought them. :) boy are they ever sticky! I haven't had a chance to get on a track yet tho (driver's school for me) before the whole covid thing happened, but hopefully next couple years I can make a set of tires look as well loved as those tires of yours.
 

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Do you have aftermarket wheels? I don't believe Bridgestone makes the RE-71R in a size that safely fits our OEM 19" or 20" wheels. I wish they did but I ended up going with Firestone's Firehawk Indy 500 because of the available sizes.
 

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Oem 19’s.

“they say” to keep OD < 3%, less than 1% is better. I couldn’t stay within 1%, but the RE71R is available in 2.x% smaller. Something like 2.7, the online calcs will tell you.

ends up being about a 1mph differential at 60. I put my CC on at 77 when commuting @ 75 mph to work and god bless it.

Should accelerate faster, but I doubt I could measure that. I don’t need the fastest top speed either.
 

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If you get 9.5” wide 19’s you can match OEM diameter by going with 265 (i think) mm wide tires. Its a perfect match.

I chose not to go there to save the $2500 on budget friendly rotary forged wheels
 

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Good to see you having fun. My brother does AutoX and track in his modified 2014 Miata perhaps the opposite of your AMG. You need some race tires that might last 10,000 miles. He pretty much beats most cars in the corners but loses in the straights to the accelerator cars like the AMG. I bought my base 250 4-matic to be a ski car and my 2000 Boxster roadster would be good for AutoX or track but much slower than your AMG on the straights. Both the Boxster and GLA 250 have similar 0-60 just under 6 seconds. If you could lower the AMG to 4”, you would be competitive after gaining time and experience in racing. Most important is the fun you are having! Hope we see more posts on competition.
 

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Oem 19’s.

“they say” to keep OD < 3%, less than 1% is better. I couldn’t stay within 1%, but the RE71R is available in 2.x% smaller. Something like 2.7, the online calcs will tell you.

ends up being about a 1mph differential at 60. I put my CC on at 77 when commuting @ 75 mph to work and god bless it.

Should accelerate faster, but I doubt I could measure that. I don’t need the fastest top speed either.
Oem 19’s.

“they say” to keep OD < 3%, less than 1% is better. I couldn’t stay within 1%, but the RE71R is available in 2.x% smaller. Something like 2.7, the online calcs will tell you.

ends up being about a 1mph differential at 60. I put my CC on at 77 when commuting @ 75 mph to work and god bless it.

Should accelerate faster, but I doubt I could measure that. I don’t need the fastest top speed either.
I'm on factory 19" wheels too. What size are the tires?
 

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What Class did they put your car in?
 
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