STX Rules and Setup Questions

[ApexEight]

Just gotta get this out there.

I really want to make the jump to STX. It would allow literally everything I want to do/have done with my BRZ.

I think the biggest hurdle for me will be wheels and tires, in terms of budget.

Are 17x9 with 245s or 255s necessary to be comeptitive locally?

What if I just got some 17x7.5s and threw some sticky 225s on them?

I don't see myself trying to be anywhere near nationally competitive. I do have access to tracks near me that I would like to take advantage of. It seems like autocrossers value 17x9s with 245s or 255s more than the track guys.

Arghh Idk. Just thinking out loud.

[G_Ride]

Originally Posted by ApexEight

Just gotta get this out there.

I really want to make the jump to STX. It would allow literally everything I want to do/have done with my BRZ.

I think the biggest hurdle for me will be wheels and tires, in terms of budget.

Are 17x9 with 245s or 255s necessary to be comeptitive locally?

What if I just got some 17x7.5s and threw some sticky 225s on them?

I don't see myself trying to be anywhere near nationally competitive. I do have access to tracks near me that I would like to take advantage of. It seems like autocrossers value 17x9s with 245s or 255s more than the track guys.

Arghh Idk. Just thinking out loud.

Where I am, you need 17x9 with 245s. Could you be competitive with 17x7.5 and 225s? It's possible. You tell us: what's the competition like in your area? How well do you stack against them currently? What do you have right now?

[14stu]

Originally Posted by ApexEight

Just gotta get this out there.

I really want to make the jump to STX. It would allow literally everything I want to do/have done with my BRZ.

I think the biggest hurdle for me will be wheels and tires, in terms of budget.

Are 17x9 with 245s or 255s necessary to be comeptitive locally?

What if I just got some 17x7.5s and threw some sticky 225s on them?

I don't see myself trying to be anywhere near nationally competitive. I do have access to tracks near me that I would like to take advantage of. It seems like autocrossers value 17x9s with 245s or 255s more than the track guys.

Arghh Idk. Just thinking out loud.

If you are getting new wheels, there isn't much cost difference between 17x7.5 and 17x9. You can run a 225 on a 9" wheel, if tire costs are a concern ($50 difference per set, you can cut the difference if you go to a 245/45/17). I was noticeably faster (2s on a 1.7mi, 1:30 track) on a 245 tire than a 225 on the track (only difference was the tire size and the track days were with the same weather/track conditions a week apart).

Local competition varies greatly from region to region. My region has half a dozen super fast STX drivers and every hundredth counts; however, other regions have a couple of half prepped cars with casual drivers.

If you don't care about being competitive, why prep the car at all? You might want to consider the new SSC class, mods are limited and reasonable.

[strat61caster]

Originally Posted by ApexEight

What if I just got some 17x7.5s and threw some sticky 225s on them?

You'll also need the RIGHT 225's, if you're on a tire that's not as fast as the BFG Rival S 1.5 or RE71R it won't matter what size you chose you'll be >1s off a competitive time (unless nobody is taking it too seriously).

I agree with the other two, start showing up before you start buying mods, pay attention to your competitors, ask questions. It won't matter if you're on crap tires, unmodified, uncompetitive, if you're just starting out you have fucktons to learn. Don't be afraid of a big budget build because you can drive the wheels off a low budget build and be competitive with enough effort put in.

[ApexEight]

I don't run SCCA, but a third-party autocross organization, so to speak. Atlanta SCCA gives me less runs at the same price, and I would have to work more, and the tracks are shorter. I get ~60s tracks with my current club, but I've heard that Atlanta SCCA has tracks that are as low as 35s. That does not seem worth it to me. I do have access to PCA and BMWCCA autocross events though.

The organization I run with now usually gets a turnout of around 60-65 cars. I haven't been to many events and am new to autocross relatively, with only a total of 5 events under my belt: two in my old Genesis Coupe, two in my old FR-S, and one in my new-to-me BRZ.

I think I just need to attend more events on my current tires to figure out which direction I really want to go toward and how much I actually want to be competitive. I can drive, but boy do I have a lot to learn.

DS is attractive because of its low cost, but STX allows me to mod with parts that I believe give huge benefits for their cost (Whiteline poly steering rack, trans, diff and subframe inserts, shifter springs and bushings, etc). Local DS and STX competition isn't super deep, but enough to have some fun in. I wish SSC allowed poly.

I'm currently on 225/45 Pirelli P Zero All Season Plus tires. They probably have more grip than the stock Primacies (I've never driven on those for extended periods of time) and they beat out the Michelin Pilot Sport A/S 3+ on TireRack. They seem to be good tires, but I have an itch for a dual duty 200 TW tire like the RT615K+. I've never had 200 TW summer tires on any of my cars and I crave grip, but the car is a daily first, but I want to turn it into the "ultimate dual duty daily driver/locally somewhat competitive autocross/2-3 track days a year" BRZ, all while being on a bang-for-the-buck mindset and never paying a large amount of money to improve any one area of the car (like dropping a lump sum at once like $1,000+ on a set of wheels, even though I know that's really not that much for a set of good wheels). I'm not broke and it's not like I'm barely affording my BRZ or this hobby; I have a solid career but I just don't want to spend so much on my car and stuff. Idk. I've got other aspirations and goals too. Even though I think about cars and my BRZ an unhealthily amount of time. Like, I'm literally on this forum all fucking day lol.

I think I just need to get some camber bolts, throw on my Whiteline shit and my Strano FSB, get a good alignment and just drive until these Pirellis are toast and get as much seat time as possible. I do have an opportunity to trade my tires plus around $200 for a set of 225/45 Super Sports but I'm afraid it won't be big enough of an improvement to justify the expense and just make me wish I saved for some 200 TW tires.

Anyway, thanks for the replies and letting me vent lol.

[14stu]

The nice thing about wheels is that you can sell them when you are done (or use them forever) for most of what you paid for them. Bushings don't do much, they increase NVH more than performance (I've done them).

RE71r's will cut 2s off a 60s course over your current tires. The 245s are worth 0.1-0.25s over the 225s (this is highly course dependent).

After tires, the only big performance gain is in coilovers, but you're going to have to spend $2k or more for ones that are worth it, you'll also need a corner balance and alignment which will add another $500 (suspension mods add up to about a second at both autox and the track).

Headers, exhaust, and a tune will set you back another $1k-$2k (good for a couple of tenths at autox and a second at the track).

Every bushing you can do will get you maybe a tenth.

SSC is going to have a spec tire (the test car ran 225 Hankook RS4's, which aren't as fast as the RE71r's but they are cheaper) and is limited to an 17x8 wheel (tire rack has a light, cheap set that the test car ran). SSC is supposed to cost about $1900 plus wheels and tires (another $1208 +shipping). You'll still need a corner balance and alignment.

The best part about SSC would be that you'd be fully prepped for the class and wouldn't be allowed to do anything else. As long as the class exists you can sell your parts for close to what you paid, you never have to wonder if throwing more money at the car would help, and you'll be running a cheaper tire without being less competitive.

I bet nearly all the STX guys would have gone SSC if it had existed before they started modding. I know I would have (and I would have been very happy with that setup at both autox and track). The only thing you can't fix in SSC is the torque dip and the fuel cut at redline (they might allow tuning in the future, but they'll never allow headers).

[DeshuL]

I need some setup help here...

I have Feal 441s with 8k/7k, 22mm front sway and OEM rear bar. My alignment is -3 front with 1* toe out, and -2.2 rear with 0 toe. I have my dampening 4 clicks off full soft in the front and about 8-10 off full soft in the rear.

My car is prone to understeer and loves to push, should I drop the front to a 19mm bar?I'm thinking that'll make a difference, any imput?

[cjd]

Originally Posted by DeshuL

I need some setup help here...

I have Feal 441s with 8k/7k, 22mm front sway and OEM rear bar. My alignment is -3 front with 1* toe out, and -2.2 rear with 0 toe. I have my dampening 4 clicks off full soft in the front and about 8-10 off full soft in the rear.

My car is prone to understeer and loves to push, should I drop the front to a 19mm bar?I'm thinking that'll make a difference, any imput?

The common starting setup is square spring rates and a 19mm (or the Strano) fsb. And usually not toe out till you're fine tuning... Your big front bar and higher front spring rates are contributing... I can't speak to the toe, but it could also be hurting things. That seems like a lot of toe out...

One change at a time though...

[14stu]

Originally Posted by DeshuL

I need some setup help here...

I have Feal 441s with 8k/7k, 22mm front sway and OEM rear bar. My alignment is -3 front with 1* toe out, and -2.2 rear with 0 toe. I have my dampening 4 clicks off full soft in the front and about 8-10 off full soft in the rear.

My car is prone to understeer and loves to push, should I drop the front to a 19mm bar?I'm thinking that'll make a difference, any imput?

You an also try a stiffer rear bar, I'm using the WRX/Forrester XT bar and it did the trick for me. It's also super cheap is you guy one off of NASIOC.

[strat61caster]

Originally Posted by DeshuL

I need some setup help here...

I have Feal 441s with 8k/7k, 22mm front sway and OEM rear bar. My alignment is -3 front with 1* toe out, and -2.2 rear with 0 toe. I have my dampening 4 clicks off full soft in the front and about 8-10 off full soft in the rear.

My car is prone to understeer and loves to push, should I drop the front to a 19mm bar?I'm thinking that'll make a difference, any imput?

First off I hope that's a typo and you mean 0.1 degrees of toe out, if you're really running 1.0 degrees of toe out I'd change that first as you're basically scrubbing your fronts all the time which could be causing a push.

It all depends on WHY it's pushing. I agree with @cjd in that your setup has a really stiff front compared to 'baseline', but I'm not positive if baseline (equal spring rates, slightly larger front bar) is a good barometer any more. The double edged sword of ST* is that with dozens of different things you can adjust it's hard to tell where to start.

I'd try softening the front as well, hell with that setup if the front felt too stiff and you can feel the rear rolling over while you drive I'd be tempted to try unhooking the front bar completely before spending $200. How the car FEELS should dictate what you do, there's a difference between understeer induced due to alignment not getting full use of the tire, and too stiffly sprung and too much air pressure, and just plain driver induced understeer. What's too pushy for someone can be too loose for someone else.

You really gotta put in the test n' tune time and driver practice time to build a good ST* car.

time/money/energy are in short supply

Edit: And as above stiffening the rear could also help find balance and diagnose an overly stiff front. You could also jack up rear tire pressures, same effect, way less time/effort/money basically proving that the issue is a lack of grip up front by removing grip from the rear.

[DeshuL]

Yes typo on the front toe, it's 1/10th toe out.

I'm going to try doing 8k springs in the rear also, and get the car realigned and corner balanced as well. I have another event in two weeks so I'll see how that improves.

Thank you all for the input.

[cjd]

Originally Posted by DeshuL

Yes typo on the front toe, it's 1/10th toe out.

I'm going to try doing 8k springs in the rear also, and get the car realigned and corner balanced as well. I have another event in two weeks so I'll see how that improves.

Thank you all for the input.

What tires, and what pressures are you running?

That alone can change the character of things.

I'll second the option of playing with the adjustments you have already, first. If those things help, you know the bigger (more expensive) change will help. If they don't help, check the nut behind the wheel.

Also, getting on the power too early is an easy way to find understeer... going in too hot, too abrupt a transition causing the front tires to break loose or plough... many things will lower front grip and it's really hard to get back.

[Silver Ignition]

Anyone know the legality of a front strut lift spacer for STX?


Looking at 14.5.B it seems like it may fall under "changes in suspension geometry" although that may pertain just to ball joint mounting points. Right after that it says it allows strut length changes to accommodate ride height and suspension travel (which is what I'm trying to achieve)

[bslate3]

Congrats to Lugod on the STX victory at Solo Nationals!

It was a fun experience. It was nice to meet some new people!

See y'all next year hopefully with a better prepped car!