Proposed changes for '18

[focusedintntions]

I had hoped that my gts2 e36 m3 would be a fun crossover to st4. But with the ruleset changing from 4 to 6 points it'll be impossible for my car to compete in this class against any properly built cars. This would definitely have to be a gts3 car to have any shot in 4. I hope 5 comes around and is sensible.

 

Also I would like to add we should allow canards. Seems silly that the class allows 10k suspension, 10k diff, 10k in brakes, but then some $200 canards aren't allowed b/c of "cost control". That ban essential kills the most popularly used airdamn/splitter for e36's.

 

who's spending 10k on a diff or brakes?

 

 

Price out a full pfc motorsport setup for an e46 or fully built diff from diffsonline. The a la cart stuff on the website is just the tip of the iceberg of what some of the guys I know have done. Not common, but allowed under current st4 rules.

[DanielsDM]

 

 

On the left of this picture, a stack of Hankook 245/17. In the middle are my 245/17 Hoosiers, and to the right are Tom Tangs 275 Hankooks. Some takeaways 1)no, Tom does NOT have a tire advantage over me because he runs 275 . They are, fact the same size. 2) I don't care how many points you give me, its hard to give up 4" tire. Look at how small those 245 hankooks are.

 

The ST/TT rules always use the manufacturers stated Tire Width number when classifying a tire. We should change this to MEASURED TREAD WIDTH when assigning points. Hoosier is only the chosen tire because it grossly under-reports on its tire width, meaning we simply have a larger tire when we run it(not because of some innate superiority in the brand). You also cannot count on the stamp on the side of the tire to be accurate within the same brand! The Hoosier 245/15 is MUCH wider than the 245/17, for example. So if you penalize all hoosiers, you might be penalizing larger sizes for no reason, because their number may be closer to the true number. You just don't know unless you measure them.

 

Wow, that picture really shows the differences. +1 on using measured tread width over sidewall numbers. Or at least go off the published specs. According to what is listed on TireRack the Hoosier 245/17 is 9.7" tread width and the Hankook 245/17 is 9.1"

[Charliehayes22]

I vote no on the tire change. Unless you classify a certain purple tire company in there correct size groups, not going off what's written on the sidewall. That will make it harder on tech and not be a good thing.

 

Leave it max 275 and call macaroni.

 

Like mentioned many times the heavy car was a-ok the "small" tires and did just fine waxing everyone. This class is to new, leave it be.

 

ABS should be open with a penalty. -.2 or -.3

 

Again as mentioned before BMWs have a huge advantage with the rules and the "stock 3 series" abs unit. This is easily flashed to compete with Bosch Motorsport versions for a 1/4 of the price.

 

One rule should be effective immediately is limiting ESR's posts.

[Savington]

Reposting this from the other thread. There was some good discussion around how best to measure power area to balance peaky vs. flat powerbands without making it so wide that it invites further gamesmanship.

 

6 points is not going to do what people thinks it will. It will just open it up to more power games. I don't think that is the intention of class. I will reiterate that we should decrease the partition size. I mean its ST, we are already pretty used to complicated forms and calculators .

 

As someone who has played the flat power game, I agree with this. Opening to 6 points opens up a world of possibilities for those who can easily tune their powerbands (any DBW car, any turbo car, any car with a standalone and variable valve timing). If you expand the measured power area beyond the RPM range actually used on track, the potential for powerband tweaking goes up dramatically. If I never use the 4400-490rpm range on track, but it's counted in the rules, that opens up a huge opportunity for me to artificially draw down my average power and increase my actual power.

 

I'll race next year no matter what, my car can easily be tweaked to fit whatever rules are decided on, but I think smaller partitions and a focus on the RPM range actually being used is a good idea. 1500rpm is too small, but 2500rpm is definitely too big - something like a 2000rpm band measured at 9 points (peak + every 250rpm on either side) might be a good middle ground.

[Dover]

I vote no on the tire change. Unless you classify a certain purple tire company in there correct size groups, not going off what's written on the sidewall. That will make it harder on tech and not be a good thing.

 

Leave it max 275 and call macaroni.

 

Like mentioned many times the heavy car was a-ok the "small" tires and did just fine waxing everyone. This class is to new, leave it be.

 

ABS should be open with a penalty. -.2 or -.3

 

Again as mentioned before BMWs have a huge advantage with the rules and the "stock 3 series" abs unit. This is easily flashed to compete with Bosch Motorsport versions for a 1/4 of the price.

 

One rule should be effective immediately is limiting ESR's posts.

 

 

Yes, the heavy car ran away from the field in a 3100lb car on 245s. He went to that tire for the +0.7 which suggests that the +0.7 is too much even for a heavy car. Giving a 2500lb car on 245s the same +0.7 doesn't seem fair compared to a 3000 or 3100lb car on 275s with only a +0.3. That's a tire-to-weight advantage with a power-to-weight cherry on top.

 

I like the idea of using actual measured width on the tire. I'm guessing "the heavy car" went with with the 245/40R17 with a tread width of 9.7" which compares pretty favorably to my 275/35R18 tread width of 10.3". A 30mm (1.2in) drop in section width only reduced tread width by half that amount.

 

And it's commendable that he saw this and took advantage of it. That's just smart set-up using the rules as written. It doesn't mean that the rules as written level the playing field as well as they could.

 

I don't know what the implications would be for "higher" ST classes, but maybe remove the power adjustment factors for tire width in ST4 and implement a simple scale establishing minimum weight by tire width:

 

10" 3000lbs

9" 2700lbs

8" 2400lbs

 

As for tech... Drivers stack your tires, measure the total height and divide by 4, report the average width, and set your min weight by tire. If someone questions or protests, do it again in impound. No, it's not as quick and easy as going by the misleading designation on the sidewall, but it is faster and easier than loading a car on the dyno for compliance pulls. Just an idea...

 

 

Yes on the ABS. Maybe open it up to some low-cost option for everyone with a penalty for everyone with ABS (OEM and modified).

[flier129]

One rule should be effective immediately is limiting ESR's posts.

 

+1 to that immediate rule.

 

 

Here's to hoping 2018 rules for all classes will be posted soon!

[esr]

too late Charlie,

 

I already got enough smart guys involved to out number you!

So see you guys next year.

Mission accomplished!

Happy New Year EVERYONE.

 

I vote no on the tire change. Unless you classify a certain purple tire company in there correct size groups, not going off what's written on the sidewall. That will make it harder on tech and not be a good thing.

 

Leave it max 275 and call macaroni.

 

Like mentioned many times the heavy car was a-ok the "small" tires and did just fine waxing everyone. This class is to new, leave it be.

 

ABS should be open with a penalty. -.2 or -.3

 

Again as mentioned before BMWs have a huge advantage with the rules and the "stock 3 series" abs unit. This is easily flashed to compete with Bosch Motorsport versions for a 1/4 of the price.

 

One rule should be effective immediately is limiting ESR's posts.

[Jon B.]

I vote no on the tire change. Unless you classify a certain purple tire company in there correct size groups, not going off what's written on the sidewall. That will make it harder on tech and not be a good thing.

 

Leave it max 275 and call macaroni.

 

Like mentioned many times the heavy car was a-ok the "small" tires and did just fine waxing everyone. This class is to new, leave it be.

 

ABS should be open with a penalty. -.2 or -.3

 

Again as mentioned before BMWs have a huge advantage with the rules and the "stock 3 series" abs unit. This is easily flashed to compete with Bosch Motorsport versions for a 1/4 of the price.

 

One rule should be effective immediately is limiting ESR's posts.

 

Yes. Can we please leave the tire rules alone at least for the time being? Changing 275 to an arbitrary limit such as 3000/ 3100 car will just promote building heavy, high HP cars. The middle weights (2700 - 2999) be disadvantaged unless a modifier was given, similar to how the rule is now... The lightweights, I don't think it matters all that much - see posts from those who know what they are talking about (Savington/Andrew). The rules as currently written provide a better balance/choice.

 

Greg - can you also provide more insight into a 6 pt dyno measurement? Looks like most would agree that adding a couple more points over a typical RPM range would be better than expanding the RPM range from which measurements were taken. Perhaps that was the original intention and we were making assumptions?

 

Jon B

NorCal ST4

[Brian L.]

Lots of talk on here about people gaming a 6 point system. I wish we could all easily just go back to cable throttles and this would be a lot easier .

 

To avoid people artificially lowering the bottom 1 or 2 points on a 6 point system, we simply write a rule that makes those points invalid if they deviate over a certain amount from the next higher point. The Honda's running in the class probably have the steepest natural curve? So we look at some data to make sure cars like this are not throwing out points, and we are good?

 

People seam to be forgetting about the penalty to shift, can be a tenth or more per shift. If we don't measure more points, and people continue to build motors that can run over a 4000 RPM flat curve, and never have to shift, it will become a must in the class. This is already the case in ST3, do we want this in ST4?

 

And BTW (Tony lol), this is not to hate on people that built great cars under the current rules, this is to help keep costs down in the class for the future to truly make this class great!

[944buzz]

Congratulations to Dave, Austin and Jon!

It was great to see a first year class have 14 competitors in so many different makes of cars.

There was a big difference in quality and prep level of cars at this event.

Clearly the Vette, Miata and S2000 came with fully prepared cars.

I think the rest of us weren't prepared, at least I know my car was not built to the max of the rules. It was still pretty much a PTD car with Hoosiers, air dam and wing.

The fact that Dave can get the vette to handle so well at that weight with a 245 tire is impressive.

To see a 4 cyl car and a V8 car be competitive with each other tells me that the format does not need alot of tweaking.

The 3rd to 9th place cars had similar lap times. Albeit way off the pace of the leaders.

I can't wait to race in this class again. In my opinion it is the class to be in right now.

Hopefully I will make the trek to Infineon a few times next year to race with the NorCal group.

 

See ya!

[drivinhardz06]

Lots of talk on here about people gaming a 6 point system. I wish we could all easily just go back to cable throttles and this would be a lot easier .

 

To avoid people artificially lowering the bottom 1 or 2 points on a 6 point system, we simply write a rule that makes those points invalid if they deviate over a certain amount from the next higher point. The Honda's running in the class probably have the steepest natural curve? So we look at some data to make sure cars like this are not throwing out points, and we are good?

 

If you are worried about artificially lowering points, then you are taking too large of a sample.

[brkntrxn]

As for tech... Drivers stack your tires, measure the total height and divide by 4, report the average width, and set your min weight by tire. If someone questions or protests, do it again in impound. No, it's not as quick and easy as going by the misleading designation on the sidewall, but it is faster and easier than loading a car on the dyno for compliance pulls. Just an idea...

 

 

Have you done that with the SAME tire on different width wheels? They will not measure the same even though the contact patch remains the same. I like your idea, but it would be arguable in reality.

[Greg G.]

Hi Folks,

 

We are working on both the Avg HP formula and the potential loopholes that changes could unintentionally bring (the biggest being someone adding a few data points lower in the rpm range that are not used on track and only used to lower the Avg HP number), and we are working on the tire size issue that is prevalent from the 205 to 255 size range. We think we have a solution for the tire issue, and we are researching how our proposed changes will work out in reality at the track.

[Matt@NCM]

we are working on the tire size issue that is prevalent from the 205 to 255 size range. We think we have a solution for the tire issue, and we are researching how our proposed changes will work out in reality at the track.

 

interest level over 9000

[davidfarmer]

me too......

 

we are working on the tire size issue that is prevalent from the 205 to 255 size range. We think we have a solution for the tire issue, and we are researching how our proposed changes will work out in reality at the track.

 

interest level over 9000

[Drew W.]

Greg--any general update on intentions for rolling out ST5 in 2018? I had a few people ask me about this at our AZ event this weekend--there is some interest here but people aren't sure if it's going to happen or not.

[Greg G.]

Greg--any general update on intentions for rolling out ST5 in 2018? I had a few people ask me about this at our AZ event this weekend--there is some interest here but people aren't sure if it's going to happen or not.

As of right now, we are still planning on rolling it out! We made a lot of decisions this past weekend. We are still waiting on some research being conducted, but while that is getting finished, we are working out actual rules verbiage.

[davidfarmer]

please KIS....keep it simple.........

[sperkins]

.....But we saw ST3 go the way of expensive builds that limited field parity.

 

Just like we all said that it would.

It's competition though. You don't think that's going to happen in every class? Someone will always build to the rule set. Nothing wrong with that.

Some of the ST3 rules designed to keep costs down make no sense at all. I'd just love to see some rule stability.

[davidfarmer]

I agree with Scott, someone will always be willing to spend more money and/or time. I think arbitrary things like brake size, wheels, isn't the way to go. I think tire size, weight limits (within reason) etc make the most sense. I know people want to be able to race a 4000lb car against a 2000lb car, but that's really not practical. Build the classes for the cars that more-or-less fit. I can make a 200hp corvette, but I can't make a 2000 lb corvette. Same the other way, I can make a 600hp miata, but it would be stupid to make a 3800lb miata.

 

Good luck with the tough choices.

[Blake T.]

Greg,

 

What is your target date to release the 2018 ruleset?

 

Thanks

[farberio]

Can we get clarity on the ST4 aero rules for 2018? There is a 5degree tolerance to the verticle air dam, does this also apply to the front splitter?

[Greg G.]

Greg,

 

What is your target date to release the 2018 ruleset?

 

Thanks

November 29th.

[Greg G.]

Can we get clarity on the ST4 aero rules for 2018? There is a 5degree tolerance to the verticle air dam, does this also apply to the front splitter?

No. This rule was purposely left without specific tolerance in order to prevent frivolous protests or unfair disqualifications, as horizontal is pretty simple, but can change slightly with rear ride height changes, tire pressure changes, any damage on track, etc. So, keep it horizontal, and avoid a protest or DQ.

[Chase J.]

Greg,

 

What is your target date to release the 2018 ruleset?

 

Thanks

November 29th.

 

D day!