2021 Model 3 Performance Autocross Build
MasterC17 Great write up! I could have used this info when I started developing my M3P for Autocross (AX). I'm adding my build and thoughts into the mix.
Dealer test drive:
Confession...I taxed the stock brakes on the dealer demo M3P on my test drive. I hated the lack of bolstering in the seat, the suspension didn't have what I was looking for to be competitive in the CST class for AX. But, the car was an absolute blast to drive! I LOVE the 0-60 that's quiet and super useful in AX and on the street. I should also mention we were in COVID mode at the dealer so the test drive with no sales person was convenient.
Brakes:
MPP rotors, SS lines, SRF brake fluid, MPP master cylinder brace, Carbotech X8 pads. The brakes are almost spot on. I'm going to try UP's PFC compound for Fontana Champ Tour National next week. The Carbotech pads have a little bit too much bite and I'm hoping the new UP PFC pads will have a little more modulation before lockup.
Front Upper Control Arms (FUCA):
If you are planning on AX or tracking your M3P then UP's FUCA is absolutely the best choice in my opinion. I tried the MPP first because of their simple clean design and the fact that I wasn't interested in adjusting castor. In the end I wasn't able to achieve enough camber at the ride height suitable to everyday driving (The lower you go, the greater the camber) and I wanted to experiment with castor adjustment. The UP FUCA was a solid design that allowed huge amounts of camber & castor adjustment So that's what I have on the car now.
Rear Camber & Toe Arms:
I run the UP rear camber & control arms. Their newest design allows more camber adjustment. They're also the strongest design. They're so robust Eddy of UP told me he uses a couple cresent wrenches to adjust them. Since my personality is a little on the OCD side I ordered a 28mm & 32mm wrench and cut them down to fit in the area well. The MPP camber & Toe Arms are slightly easier to adjust on the car but I was worried about the small pinch bolts. I never had an issue with them so I put it out of my head.
Swaybars:
I started out with Eibach swaybars since they appeared to have a similar diameter as UP's although less adjustability. MPP didn't offer any and I could save a couple bucks over getting the UP's. Rishie (Rishie owner of "autornd" is a great resource for everything Tesla) advised me to order lockings to bolt on the Eibach swaybars to avoid the bars "walking" side to side. The swaybars worked and I had no issues with walking thanks to Rishie. When I switched to UP coilovers I was advised that the UP swaybars worked better with them than than Eibach, so I switched to UP's swaybars and have them on the car now. The UP bars came with lockings welded on them as well as more adjustability holes.
Coilovers:
I run UP's Race spec one way adjustable coilovers and unless I come across an amazing deal for UP's two or three way adjustable set I will be running these indefinitely. Simply put, they were a game changer. I had MPP's sport coilovers and they were a huge difference from stock but they were a little too soft for the CST class. At AX events I was hesitating for the car to stabilize before turning (Body roll). On threshold braking, the front end was diving a little causing me to wait a little before turning. Here's a pic of the UP coilovers pushing over 1g in a corner. There were three large men in the car (260lbs, 205lbs, 200lbs the two big ones were on the passenger side). Look at the composure under such a load.
View attachment 654763
Sliding in the seat:
Schroth had the only harness I knew of that would allow me to run the stock seat and snap in & out easily for events. That's what I have in the car now. The next issue was the lack of bolstering by the legs. I saw a pretty fast guy in a stock Tesla (Tim) wedging a Sparco seat cushion in-between the door and his leg. I liked the concept but wanted a cleaner solution. Since I couldn't find one, I made a rubber & foam pad that Velcro's on to the door handle. I got some very funny looks from my co-driver and Tom who helps us develop the car but at the end of the day, both said they loved it.
View attachment 654762
Rear Spring Arms:
Regardless of your application, if you're replacing your rear spring arms, UP is hands down the best choice! The MPP spring arms are solid and good looking and I never had a mechanical issue with them. They collected asphalt and tire rubber in the spring seat cup but that's trivial. That being said the UP's are a dream to use. When you want to adjust ride height, all you have to do is using a socket wrench, reach under the car and turn it up or down! Seriously, it's a corner balancer's dream. No more jacking up the car, pulling off the wheel, adjusting the spring adjuster with a spanner wrench, putting the wheel back on, lowering the car off the jack, rolling the car back and forth taking a measurement and repeating until ride height is achieved.
Wheels:
I started out with Apex EC-7 18x9.5 and they work fine for 275 tires. When I made the jump to 295's I bit the bullet and sprung for UP's UP03 Race spec wheels 18x10.5" which I was able to get 295's on. I love the wheels, they're light, strong and give me a little sense of pride when They're on the car. I will use the Apex wheels until I've chewed through the 275's sitting under my house but when they're gone, I'll replace them with a set of off brand 18x10.5" wheels... Does anybody recommend an affordable practice wheel 18x10.5" that will fit over the Tesla M3P brake calipers?
Summary:
I've spent a lot of time & money developing my M3P for the CST class (Soon to be the XA class). Thank you to all the trusted sources that I've leaned heavily on (Rishie of Autornd, Ben & Eddy of UP, Jesse & Sasha of MPP, Tom, Kyle). I feel I have a very solid car and can now focus on my driving for the rest of the season. In the latest configuration we were able to finally get our first win in the CST class (**disclaimer- Tom Berry decided to race a different class that day).
View attachment 654764 Next weekend we will be racing the SCCA National Champ Tour in Fontana. The class we were hoping to run had no entrants so we will be running in the ASP class. The ASP class allows for Hoosiers... we will be running Yokohama AO52's (Since we have two sets under my house) and hoping for a miracle. I hope sharing my development helps as much as I learned from reading other peoples contributions.
