SCCA Autocross Class for the Model 3

[Stretch2727]

I ran D class in late Sept. P3D+. The car was 4 days old. Street tires. They had no idea what class to put me in so I suggest D.

It has been about 10 years since I had done any autocross.

I did ok but did find the car was hard to modulate. Almost too much power and found myself overshooting corners. In the past with other cars it was full throttle coming out of corner. With the P3D almost never could do this, alway some level of partial throttle which to me made it more difficult. I am sure with some practice I could do better.

I plan to go a few times this year. It will be interesting to try track mode. (It was not on the car yet when I went last year.) I may also try my RWD as I would like to compare. If anyone in NJ PA wants to join me let me know. Lot's of people checking out the Tesla. Only one there.

 

[SD_Engnr]

Yea, same here. I'm going to be running 9.5 wide wheels so that technically kicks me out of street even without coilovers!

i don't actually care about my class (not being competitive) it's more about scheduling the time at the course correctly

Just saw this. Not my request, but looks like someone else wanted the car classed in Street Touring.

Looks like with the wider wheels, the car will end up in D Street Prepared.

 

[Lunares]

Just saw this. Not my request, but looks like someone else wanted the car classed in Street Touring.

View attachment 374518

Looks like with the wider wheels, the car will end up in D Street Prepared.

Interesting to me that they wouldn't at least put it in STU. STU says that up to 11" rims and up to 285" tires are okay, I wouldn't meet any other ST* class due to the 9.5 rim and 265 tire I'm going to run.

 

[Joshker]

As more Model 3 AutoX'ers are starting to pop up has anyone heard anything further about correct classing for Model 3 (NON Performance cars) with wider wheels and tires?

I’m starting my journey of AutoX'ing my MR RWD Model 3. From what I can see I am DS. From there I'm a bit confused. I'm about to order tires for my 18X9.5 APEX EC-7's and was planning on 265/35/18 RE-71R’s.
Looking at the rulebook under touring 14.3/14.4 if I understand correctly Street Touring Ultra - STU is my only option for this tire and wheel combo but then under tires it states STU (AWD & 2WD mid- or rear-engine). I really don't plan on getting overly crazy with modifications (It's a Tesla) but I already have the wheels so I'd like to be in a class that I would be most competitive. Does this vehicle fit under the STU “Catch-all”: Sedans & Coupes NOC (non-sports-car-based; 4-seat minimum; over 5.1L normally aspirated or 2.0L to 3.1L forced induction)? Seems to fit overall, the power would also be consistent with the engines listed.

Obvious going to street prepared would make it non competitive. I've emailed [email protected], how else can I go about getting an answer?

 

[Daniel in SD]

I doubt you’ll be competitive in anything other than street class. Stock width wheels plus MPP party box (when it comes out) might be competitive.

 

[Joshker]

I doubt you’ll be competitive in anything other than street class. Stock width wheels plus MPP party box (when it comes out) might be competitive.

Thats disappointing. Guess I should consider selling my brand new wheels. I really wanted to run a more appropriate tire on the car.

 

[Daniel in SD]

Thats disappointing. Guess I should consider selling my brand new wheels. I really wanted to run a more appropriate tire on the car.

Going to street touring would be super tough. Check out the PAX index that allows you to compare times between different classes.
D street .800
B street .810
STU .828
So the difference between DS and STU is almost three times as large as the difference between a P and a RWD!
2019 PAX/RTP Index

 

[Lunares]

Going to street touring would be super tough. Check out the PAX index that allows you to compare times between different classes.
D street .800
B street .810
STU .828
So the difference between DS and STU is almost three times as large as the difference between a P and a RWD!
2019 PAX/RTP Index

Its about 1.6 second difference (on a course where pax standard is 60s). Big yes but also going to be swamped in general by driver skill until people are way better

 

[Daniel in SD]

Its about 1.6 second difference (on a course where pax standard is 60s). Big yes but also going to be swamped in general by driver skill until people are way better

Yes, driver skill trumps all! 1.6 seconds
I've only autocrossed my Model 3 once and only because it was raining. The stock suspension seemed perfectly fine, way better than I was expecting (beat my buddy in his P3D+! Performance Model 3 slower than AWD? Autocross results!). I used my 265/40R18 PS4S and they took a bit of wear on the outside edges even in the wet conditions.
If I were trying to be competitive I would stick to DS class.
235/40R18 Hankook RS-4 on a dedicated set of rims. All 200TW tires are pretty hard to live with day to day.
They don't make them in the stock diameter but the smaller diameter will give more torque and probably be faster.
They're symmetrical so they can be flipped and you're going to need to because the Model 3 has no camber adjustment .
They last way longer than the RE-71R
MPP Party box. It's great that street class allows stability control defeat devices.

 

[AlanSubie4Life]

Yes, driver skill trumps all! 1.6 seconds
I've only autocrossed my Model 3 once and only because it was raining. The stock suspension seemed perfectly fine, way better than I was expecting (beat my buddy in his P3D+! Performance Model 3 slower than AWD? Autocross results!). I used my 265/40R18 PS4S and they took a bit of wear on the outside edges even in the wet conditions.
If I were trying to be competitive I would stick to DS class.
235/40R18 Hankook RS-4 on a dedicated set of rims. All 200TW tires are pretty hard to live with day to day.
They don't make them in the stock diameter but the smaller diameter will give more torque and probably be faster.
They're symmetrical so they can be flipped and you're going to need to because the Model 3 has no camber adjustment .
They last way longer than the RE-71R
MPP Party box. It's great that street class allows stability control defeat devices.

This guy...he is going to keep trolling me with this embarrassment until I get off my rear and get some decent 18" (stock width) wheels for my car. I just need light cheap wheels, and 235 width tires should be fine, since the car only uses a couple inches of the outside of the front tread anyway.

But currently not worth it, as he apparently actually is the slightly better driver these days, when compared in the same vehicle. Also running the P3D porker is probably super expensive for tire wear, regardless.

 

[Drivesolo]

It's spring time here in Western WA. How do I know? The first of the local WWSCC autocross events was this past weekend and NWR-SCCA starts next weekend. I decided not to campaign my RWD TM3 this season in the WWSCC street tire class since I don't believe it can be competitive with DS index. I think the AWD can but the the RWDs should probably be in ES. First practice day is this coming Saturday, hopefully I can get some video this year with telemetry.

 

[StationaryDave]

My 3, Elektra, wants to go racing at the Atlanta SCCA event June 9. (Atlanta Region SCCA | Schedule)
Thanks to you earlier posters, I'll start out at 50 psi all around on my stock 18s. Sport suspension settings of course.
Other than tire pressure are there any other setup changes I can make at the track on a stock 3?
Dave

 

[Lunares]

My 3, Elektra, wants to go racing at the Atlanta SCCA event June 9. (Atlanta Region SCCA | Schedule)
Thanks to you earlier posters, I'll start out at 50 psi all around on my stock 18s. Sport suspension settings of course.
Other than tire pressure are there any other setup changes I can make at the track on a stock 3?
Dave

Brake pads, rotors, fluid and then suspension is all you can do besides wider tires.

I wouldn't start at 50 psi though, that's way too high. After a hot lap you would be around 53-55, that's above tire safety rating.

 

[Daniel in SD]

My 3, Elektra, wants to go racing at the Atlanta SCCA event June 9. (Atlanta Region SCCA | Schedule)
Thanks to you earlier posters, I'll start out at 50 psi all around on my stock 18s. Sport suspension settings of course.
Other than tire pressure are there any other setup changes I can make at the track on a stock 3?
Dave

There’s a good chance that you will destroy your MXM4s in a single day if you drive close to the limit. I believe @SammichLover can show you pictures. Seems like a waste of $1k to me. I think it’s worth it to get appropriate tires (Hankook R-S4 are my recommendation) mounted on dedicated rims.

 

[SammichLover]

There’s a good chance that you will destroy your MXM4s in a single day if you drive close to the limit. I believe @SammichLover can show you pictures. Seems like a waste of $1k to me. I think it’s worth it to get appropriate tires (Hankook R-S4 are my recommendation) mounted on dedicated rims.

Yes.

In some ways this picture doesn't tell the proper story. The problem I think is to keep from rolling and popping them you over-inflate (and dear god, check pressure between runs as the front will rise 1PSI or more a run) and that means you are eating the center tread even faster than at the factory pressure.

And they smelled worse. It was the smell that told me I'd killed them that day and was driving corpses afterward.

If there is a reasonable chance you'll keep doing this, but you're not entirely sure, you can do what I did after the above oopsie. Get some bargin 200tw to 300tw tires on their own bargin rims. No need for TPMS. $1250 at Tirerack got me the whole wheel set mounted and delivered to my house. With studious rotation (front is much harder on the tires) I've gotten 8 events plus 2 track days out of them so far. Only down to the tip of the wear bars now, lots left.

I actually have the wheel set for sale for the original price of the rims with the mounted tires thrown in for free, and if they sell I'll be going to RE71R on 18" that'll support larger rotor kits in case that's what I do with the brakes (need that for track, not AX).

If they don't sell I'll just drive them out and then put the top-shelf tires on these rims and drive those, for now. The rims are fine, get the job done, and I'll only need to worry about replacing them with bigger barreled rims if I don't go the Racing Brake route on rotors (those rotors are stock sized, just designed different to handle heavier braking duty, so obviously will fit under the rims I have now).

 

[StationaryDave]

There’s a good chance that you will destroy your MXM4s in a single day if you drive close to the limit. I believe @SammichLover can show you pictures. Seems like a waste of $1k to me. I think it’s worth it to get appropriate tires (Hankook R-S4 are my recommendation) mounted on dedicated rims.

Good point about the risk of ruining tires in one day. And my tires are perfect right now (as with seemingly everything with my 3) so I'll think twice about attempting driving at limit on my drive-to-work tires. Yes, getting a dedicated set of wheels and tires is the way to go if you get serious. I've seen plenty of autocrossers drive to the track on their everyday tires, pull their racers out of the back seat, and switch at the track (and back before driving home).

 

[SammichLover]

I've seen plenty of autocrossers drive to the track on their everyday tires, pull their racers out of the back seat, and switch at the track (and back before driving home).

On all seasons?

I admittedly pushed them pretty hard, but the MXM4 isn't in any way a credible AX tire and that'll lead to more than normal damage onto itself.

 

[usofrob]

I autocrossed my S 90D once with the stock all season tires, but I think I only got 4 runs in. I still managed to get to 50k miles before replacing them. Having AWD, electric motors and a very low center of gravity seems like cheating. However, being super long and wide (for a sports car) made it so that I coned 3/4 times. Still, it competed well against one of the Corvettes out there. So, I was happy.

 

[usofrob]

Just saw this. Not my request, but looks like someone else wanted the car classed in Street Touring.

View attachment 374518

Looks like with the wider wheels, the car will end up in D Street Prepared.

I'm looking at doing an autocross in a couple weeks. I have wider wheels on my car now. Is D Street Prepared the correct class to register in? I don't know how cars map through the modified classes. Does anyone have anything they can link to that explains this? When I read the SCCA rules it talks about engine sizes and other useless things.

 

[Daniel in SD]

I'm looking at doing an autocross in a couple weeks. I have wider wheels on my car now. Is D Street Prepared the correct class to register in? I don't know how cars map through the modified classes. Does anyone have anything they can link to that explains this? When I read the SCCA rules it talks about engine sizes and other useless things.

Could be FSP since it might meet the "catch all" "Sedan under 1.7L not otherwise classified"
Might actually be competitive in that class (PAX is 2% faster than B Street) if you do all the suspension mods (coilovers and camber).