Autocross megathread

[mattm]

So what you didn't do was drop in as an FL5 in the classifier. Which is what I had to do when I bought my DE5, because it wasn't in the system at the time.

Sincerely- this is exactly the type of bullshit that has kept me from giving enough of a shit to compete at a national level (and subsequently joining the SCCA).

Feel free to resort to the rulebook "or get in contact with an experienced autocrosser to help you out!" Because technically, the DE5 is NOT eligible for BST, even though the FL5 IS.

To be clear- the mechanically identical car is not allowed to compete in the same class because... your guess is as good as mine.

I operated under an assumption that the DE5 was in BST because of what's in that screenshot. GOD FORBID.

Fuck them all, honestly. Lol. I'll just stick to embarrassing Porsches.

Wait until you try to wrap your mind around the indexing math. It's just hilariously nonsensical.

Or that my MX-5 is C Street, but any significant mods bump it into... A Street Touring.

Yeah, SCCA can make things tough. I'm a 40 year member and use to the stuff. As to the legality of a ITS, have someone protest you. It'll bump up and hopefully found to be legal in the equivalent CTR classing. The only real (bad) differences are the seats. You can't thread safety harnesses through the seat on a an ITS as you can on a CTR. Had I paid attention I might have waited until the right CTR (cheap) came up. Right now I drop the seat bottom back, grab the shoulder part of the belt and "snug it up." Then I adjust the seat to the belt so it secures me in place, it is NOT my favorite set up. But for a local event or local nationals, it'll do fine. My Nats CSP ride in a Meotter and has real belts and is a hoot to drive.

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[mattm]

PCA LA since 2024 allows non-Porsches to classify and compete in Porsche classes. You can check it here: https://classification.zone8.org/ (you need to register to classify your car).
From what I know they are the only one PCA who does it. Or it will be my "Monday" talking, lol

I am advocating at PCA San Diego to adopt this system next year, too. You might want to check your local club if they are open to it.

Connecticut Valley PCA is receptive to non-Pooches (Porsches). I'm a 30 PCA member.

 

[CANDE5]

I need to fix the "nut behind the wheel."

You are NOT alone! I’ve got a long way to go also. Sure is fun figuring it out though.

 

[Sinnelizer]

So what you didn't do was drop in as an FL5 in the classifier. Which is what I had to do when I bought my DE5, because it wasn't in the system at the time.

Sincerely- this is exactly the type of bullshit that has kept me from giving enough of a shit to compete at a national level (and subsequently joining the SCCA).

Feel free to resort to the rulebook "or get in contact with an experienced autocrosser to help you out!" Because technically, the DE5 is NOT eligible for BST, even though the FL5 IS.

To be clear- the mechanically identical car is not allowed to compete in the same class because... your guess is as good as mine.

I operated under an assumption that the DE5 was in BST because of what's in that screenshot. GOD FORBID.

Fuck them all, honestly. Lol. I'll just stick to embarrassing Porsches.

Wait until you try to wrap your mind around the indexing math. It's just hilariously nonsensical.

Or that my MX-5 is C Street, but any significant mods bump it into... A Street Touring.

Wait, but SCCA explicitly says it is Unofficial Solo Car Classifier. The book says:
B Street Touring (BST) – Primarily mid-to-high power and performing sports cars, coupes, AWD sedans, and hatchbacks.
So fk them. You stick to the official rules book.
I'd let them protest.

 

[optronix]

PCA LA since 2024 allows non-Porsches to classify and compete in Porsche classes. You can check it here: https://classification.zone8.org/ (you need to register to classify your car).
From what I know they are the only one PCA who does it. Or it will be my "Monday" talking, lol

I am advocating at PCA San Diego to adopt this system next year, too. You might want to check your local club if they are open to it.

I just go after them on raw times. I'm usually faster than anything that isn't a GT car. There are a couple exceptions in 718s but also they are exceptional drivers.

 

[Sinnelizer]

Looking for some input on tires.

I've got a bit of a unique situation. I live in an area without street addresses, so no deliveries to my door. I have a PO box, but Apex Wheels won't ship there. I talked to my local Discount Tire — the guys I take my car to after every autocross event for free rotations (I just tip them $20) — and they agreed to let me order Apex wheels directly to their shop if I buy the tires through them.

For 18x9.5 wheels, their only 200TW option is the Falken Azenis RT615K in 275/35/R18 95W SL BSW, at $310 per tire.

Has anyone here run these at autocross? How do they perform? Are they a solid choice, or should I steer clear?

Thanks!

PS @optronix I remember you warned about size 19 - wet and chilly conditions. I wonder if 18 is any different compound-wise.

 

[Sinnelizer]

Another quick question for those running Apex wheels on their DE5.

I know Apex requires 60° conical seat lug nuts, but I want to double-check the exact specs before I order or reuse what I already have. What's the correct size for the DE5 Integra Type S?

• Diameter: M14 or M12?
• Thread pitch: 1.25mm or 1.5mm?

Also, while I'm at it — do I need to upgrade to aftermarket wheel studs, or are the factory ones fine with these wheels?

For context, I do have a set of M14 wheel studs sitting around from my old Camaro. Any chance those would work?

@Victorofhavoc I guess, you'll know it better.

Thanks!

 

[Victorofhavoc]

Another quick question for those running Apex wheels on their DE5.

I know Apex requires 60° conical seat lug nuts, but I want to double-check the exact specs before I order or reuse what I already have. What's the correct size for the DE5 Integra Type S?

• Diameter: M14 or M12?
• Thread pitch: 1.25mm or 1.5mm?

Also, while I'm at it — do I need to upgrade to aftermarket wheel studs, or are the factory ones fine with these wheels?

For context, I do have a set of M14 wheel studs sitting around from my old Camaro. Any chance those would work?

@Victorofhavoc I guess, you'll know it better.

Thanks!

Stock studs work fine. M14x1.5 is the correct size.

 

[optronix]

Looking for some input on tires.

I've got a bit of a unique situation. I live in an area without street addresses, so no deliveries to my door. I have a PO box, but Apex Wheels won't ship there. I talked to my local Discount Tire — the guys I take my car to after every autocross event for free rotations (I just tip them $20) — and they agreed to let me order Apex wheels directly to their shop if I buy the tires through them.

For 18x9.5 wheels, their only 200TW option is the Falken Azenis RT615K in 275/35/R18 95W SL BSW, at $310 per tire.

Has anyone here run these at autocross? How do they perform? Are they a solid choice, or should I steer clear?

Thanks!

PS @optronix I remember you warned about size 19 - wet and chilly conditions. I wonder if 18 is any different compound-wise.

The RT660 is what I used. The RT615 is a more "endurance" type tire; not necessarily ideal for autocross relative the RT660. It is still a 200 TW tire though so not like it's a bad choice- there are just better choices and for the money you're spending on tires that are explicitly for the purpose of autocross I'd encourage you to consider getting exactly what you want.

As for the grip on the RT660, I actually really liked them- until I got in the cold or wet. Neither of those issues will be common in your situation so they'd actually be pretty good options for you, even in 18. In 18', the compound won't be any different but there will be some different characteristics from a larger sidewall that will play a role in how the car feels and grips. To be completely honest, I didn't really notice a huge difference going from 19" Falkens to the 18" Bridgestones as far as feel... but yes, there was a significant difference in grip. That also might have something to do with the sidewall on the Bridgestones being very, very stiff relative even to other 18" tires.

Plain and simple, the Bridgestones have proven time and again to be the fastest tire. But as you're developing your skills, it isn't necessarily a requirement for you to get THE fastest tire. But as I mentioned earlier, you're already spending the money... unless the 615s can be had at a steal I'm not sure I'd recommend them over the Bridgestones (they might actually be a few hundred dollars cheaper now that I think about it so there is that). But one advantage they would have is they will last longer than most other 200 TW tires. That is actually a pretty significant consideration as you're "learning the ropes" with autocrossing a FWD car.

 

[Victorofhavoc]

I agree with what @optronix said there.

Most new drivers in autox and road course stuff tend to cook tires as they learn. This makes rubber disappear very quickly, and tires also have a number of heat cycles before they fall off which frustrates newer drivers who overheat them a lot. The grippier tires are peakier and more sensitive to cycling so there's something to be said about a more durable tire making a better driver through consistency. Pace comes with time.

 

[Sinnelizer]

I agree with what @optronix said there.

Most new drivers in autox and road course stuff tend to cook tires as they learn. This makes rubber disappear very quickly, and tires also have a number of heat cycles before they fall off which frustrates newer drivers who overheat them a lot. The grippier tires are peakier and more sensitive to cycling so there's something to be said about a more durable tire making a better driver through consistency. Pace comes with time.

Thank you, tribe!

@optronix Are you talking about this tires? https://tires.bridgestone.com/en-us/tires/automotive/potenza/re-71rz I love ho Bridgestone doesn't publish TW on their site. Or I just can't find it anywhere.

 

[optronix]

Thank you, tribe!

@optronix Are you talking about this tires? https://tires.bridgestone.com/en-us/tires/automotive/potenza/re-71rz I love ho Bridgestone doesn't publish TW on their site. Or I just can't find it anywhere.

Yes sorry, I totally glossed over the fact that Bridgestone makes a ton of different tires. Yes, definitely RE-71RZ (RS are great too if you can still find them, the RZ superseded them)- they were a noticeable step up even over the Falken RT660. The OEM Potenza S001s on my MX-5 for example are the rough equivalent of the OEM PS4S on the DE5, except worse in every category. Don't get those.

I'm a bit of a tire snob now, I'll admit. Ever since I tried the Falkens I'm convinced it's a true "night and day" difference and I basically refuse to engage in any autocross or track events on summer tires (also they disintegrate).

That said, I kept my Apex wheels around strictly because I prefer the street manners of the PS4S. The RE-71RZ are kind of obnoxious, and not super fun to drive in the rain with the camber I have.

 

[Victorofhavoc]

Yes sorry, I totally glossed over the fact that Bridgestone makes a ton of different tires. Yes, definitely RE-71RZ (RS are great too if you can still find them, the RZ superseded them)- they were a noticeable step up even over the Falken RT660. The OEM Potenza S001s on my MX-5 for example are the rough equivalent of the OEM PS4S on the DE5, except worse in every category. Don't get those.

I'm a bit of a tire snob now, I'll admit. Ever since I tried the Falkens I'm convinced it's a true "night and day" difference and I basically refuse to engage in any autocross or track events on summer tires (also they disintegrate).

That said, I kept my Apex wheels around strictly because I prefer the street manners of the PS4S. The RE-71RZ are kind of obnoxious, and not super fun to drive in the rain with the camber I have.

I think you meant you won't use a 300tw summer .

It's funny, though, the ps4s can turn a high speed lap as well as almost any 200tw for about 2.5 laps and then they're falling off. I've seen them peak at 1.2G on track and this past weekend I was in civic type r with them on. With a little guidance he was able to catch a bunch of cars on 200tw tires because he was hitting 1 to 1.1G (it's nice the type r has a display I can watch as a passenger) while they were still working on their line. High speed they have enough time to cool the shoulders and start to grip again where autox you're just riding shoulder.

The ps4s are certainly better than the old crop of 200tw and even the r888r/nt01 Gen of tires.

 

[optronix]

I think you meant you won't use a 300tw summer .

It's funny, though, the ps4s can turn a high speed lap as well as almost any 200tw for about 2.5 laps and then they're falling off. I've seen them peak at 1.2G on track and this past weekend I was in civic type r with them on. With a little guidance he was able to catch a bunch of cars on 200tw tires because he was hitting 1 to 1.1G (it's nice the type r has a display I can watch as a passenger) while they were still working on their line. High speed they have enough time to cool the shoulders and start to grip again where autox you're just riding shoulder.

The ps4s are certainly better than the old crop of 200tw and even the r888r/nt01 Gen of tires.

I can somewhat reconcile with that, as I did not have a problem with grip at all the one time I took the car to the track at Dominion Raceway on the PS4S. I was intentionally going only about 8/10ths (except on straights... I backed off WAY early because OEM pads/fluid). BUT- autocross? No kidding I think I picked up about 2 seconds or so off my PS4S pace with the Falkens, even more with the Bridgestones. They're not comparable IMHO. On top of the fact that they disentegrate.

That said, there is one notable exception- one guy, a very good driver, I'm usually in a knife fight with in his Z4 on PS4S. As I understand it the Z4 is basically a drop top Supra, so there is that- but he's the only one who routinely gives me fits even though he's not on "real" tires.

Virtually anyone else, I can take one look at their tires and feel confident I'll be faster, regardless of what they're driving. I swear that was NOT the case while I was still on PS4S...

Take that for what it's worth, it's just my experience... and I don't have enough seat time in a track setting to comment other than yes they held up well and didn't actively hold me back the one time I went.

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