ST4 Rules Proposal Thread--give your input here

[Greg G.]

Hi Guys,

 

Well, the '16 ST Rules are out, and the Calculator tool, new ST/PT/TT Dyno Certification Form and ST Car Classification Forms will all be out within a week. So, it seems to me that it was very helpful this past year to have a few threads where drivers and potential new ST competitors had a chance to give their input and ideas in regard to specific rule items that were up for consideration. In fact, these discussions not only lead to both making some changes and not making changes to the rules, but also lead to some new ideas that were either implemented for '16 or put into the pipeline for '17 and beyond. And, as you know, while we appreciate driver input and take it into consideration, our goal is to always improve and grow the series, which means that ultimately it comes down to the series officials making the decisions on the rules, as opposed to a vote or mob rule. We always understand that regardless of what decisions are made, whether they be to make changes or not do anything, some percentage of the competitors will not be satisfied, and some will be very vocal. With that being said, we all need to remember that the large majority of competitors never actually look at (or certainly post) on these forums (unfortunately). So, just because there is some high volume about a given topic here, does not mean that that sentiment is common or the majority opinion around the country. However, we also know that those of you who take the extra time to follow these forums are often well informed, intelligent, and have some valid points and ideas that we appreciate. So, now that I'm done with my disclaimer:

 

ST4 is definitely planned for '17. Now, whether it ends up being called ST4 or PT4 or something else is still up for a final decision, but I suspect it will be ST4. The idea is to extend the ST series classing scheme down to the lower HP and higher Adjusted Wt/HP Ratio vehicles. And, the current plan is to set that class at a limit of Adjusted Wt/HP Ratio of 12:1 (using the Avg HP calculation that is being tested in '16 in ST3). The goal is to attract new competitors that are neither competing in ST (because they have difficulty reaching 10:1 for ST3) or PTB/PTC (because they have difficulty with the points system), and to increase field sizes of the cars that are competing in PTB currently. Assuming we add ST4 (PT4, etc.) as a new class, we would delete at least one class, which in this case would be PTB (with a consideration for PTC, but that would likely depend on whether ST5/6 (PT 5/6) become reality as well (see other thread).

 

So, what are we asking? As you know, unlike some other open classes, our philosophy in ST is that as we move further away from Super Unlimited, there necessarily needs to be either increased vehicle restrictions and/or an increased number of Modification Factors and/or an increased value of current Modification Factors in order to help contain costs to the competitors. While we understand that these rules do not directly prevent someone from spending a million dollars on a build, they definitely can limit the advantage gained by doing so. It does not make sense to ST officials to have vehicles that cost $3000-$7000 to purchase to essentially be required to have $40,000++ of modifications to be competitive. As you know, ST1 and ST2 have the same rules with just the exception of the different limit on Adjusted Wt/HP Ratio. This is appropriate, as these vehicles tend to be much more expensive to begin with, and it is understood that these are going to be fairly high dollar classes. ST3 is where some of these controls start to kick in, with the OEM Aero rule that allows drivers to choose to stick with OEM Aero, and the higher Modification Factor for a non-OEM sequential/semi-automatic transmission. We believe that ST4 should have an expansion of this philosophy, but we are just beginning to work on what these additional controls might look like. Additionally, we have not decided the extent of these additional controls, and it may turn out that we decide that we don't want any, and to have ST4 just mirror ST3 with a different Adjusted Wt/HP Ratio. This is where we would like this thread to focus. Please feel free to give your input on ideas for these additional controls, or the extent of the controls, or whether you don't think there should be any. Valid arguments can be made for all of these cases, so try not to judge each other or make personal attacks, but if you wish to constructively comment on ideas submitted here without getting nasty, feel free.

 

So, I'll start with my personal opinion. I think that ST4 should be ST4, a true extension of the ST series, and that any classes below this that may require significant differences, like a vehicle model Modification Factor table, might be best served as sticking under the PT series label. So, in that light, I think that the extent of the differences between ST3 and ST4 should be small, which will increase the draw to new competitors as less restrictions allow for more cross-classing from other series that either do or don't have restrictions. At the same time, this may mean that those in PTB will have to decide on whether to improve on their current builds or not. But, I also think that we should probably have a few additional controls. The proposed rule for quarter panels for ST3 that failed to make it to the rules may be one example. Another example may be further restrictions on Aero to some type of defined modification parameters, or perhaps a restriction on "A" tires or Mod Factor for "A" tires. I have some other ideas, but I'd rather see how many come up with the same ideas.

 

I'm starting a similar thread for ST5/6 (PT5/6), that will necessarily have significant additional controls as we don't want these series to end up requiring a $250K car to be the champion of the lowest level class.

 

Thanks for your input, and have a great 2016 season!

[bpanther]

Our current ST3 car is well underpowered with the new averaged ST3 dyno calcs. Great position to be in for me!!! Except, there is no more weight to take out. And, I don't want to spend a $2-3k to get the 40 hp I could use. So if there was ST4 (and associated competitors tp race against), I'd switch now. If, of course I could keep my non OEM car, slicks, etc.

 

Main question from my mind - will there enough under-powered ST3 cars or PTB cars wanting to jump to ST4 in 2017?

[Luke P.]

I used to run my car in TTB but when I upgraded for GTS I had work done to my chassis and cage which prevents that cross over. I have a 14.5 power to weight but could go unrestricted and pull ballast to get close to 12. What I'd suggest is to give consideration that there are many cars like mine with a beefed up chassis but relatively low power. I'd take a mod factor but don't want to be killed for reinforcements that sometimes enhance performance but other times are for reliability. Id be interested in crossing over and dicing with cars of other makes. That is the essence of touring car racing after all.

[Arca_ex]

Make ST4 just like ST3, if you want to create mod factors to keep costs down then do that, but don't introduce model specific mod factors, keep the playing field level.

[Ryan S.]

I agree with Greg on if it's going to be an ST class it needs to follow the same progression. Since the underlying theme is to try and rein in spending through power to weight ratio, and the ratio is targeted at 12:1 I think just heavier penalties that highlight the progression from the slower class to SU. Such as 1.0 for Aero modifications. It may seam excessive but at the lower power levels it could account for more the 0.4 in ST3. I would also propose an out right banning of driver aids, ABS, traction control, and stability control explicitly, because a lot of the cars that are going to fit the 12:1 ratio won't have the luxury of those things being factory available and if they are available they may be of a performance level not appropriate for motorsports anyway.

 

My $0.02 anyway.

 

Ryan

[Arca_ex]

I would also propose an out right banning of driver aids, ABS, traction control, and stability control explicitly, because a lot of the cars that are going to fit the 12:1 ratio won't have the luxury of those things being factory available and if they are available they may be of a performance level not appropriate for motorsports anyway.

 

My $0.02 anyway.

 

Ryan

 

 

Banning ABS is a terrible idea. Do you realize that almost all cars come with it and it is not simple to disable or remove from most cars? I don't view it as an advantage either. Same goes for stability control. Most of the time it's a huge hinderance. The traction control rule might be carried over as a mod factor but it's so hard to police, and what if you can't shut it off completely?

[Ryan S.]

 

Banning ABS is a terrible idea. Do you realize that almost all cars come with it and it is not simple to disable or remove from most cars? I don't view it as an advantage either. Same goes for stability control. Most of the time it's a huge hinderance. The traction control rule might be carried over as a mod factor but it's so hard to police, and what if you can't shut it off completely?

 

I would disagree, ABS is pretty big aid and its also pretty easy to get rid of too.

 

https://lefthanderchassis.com/v2a/14_viewproduct_product.asp?idproduct=0063403342

 

Now if you are talking hindrance from your experience with an RX8 (Im assuming you drive an RX8 because of your avatar) I completely agree, that equipment sucks, but an out right ban would prevent someone from adding in say a bosch motorsports system, or using the functionality of a motec ECU. So think of it from that perspective, it is possible to have unfairly good stuff ("unfair" from the dollar perspective) so an out right ban puts the driving task on the driver, why wold any of us be opposed to that idea. And its not hard to police, no funny stuff between the master cylinder and the caliper and a cable actuated throttle. (Yes yes traction control can still be had in through manipulation of the timing and the fuel, but that really sucks)

[ILIKETODRIVE]

Don't ban them. Make the wording OEM only or removal.

 

Eliminates wacky awesome aftermarket systems. Doesn't hinder people that want to keep functional OEM ABS. BAM

[Greg G.]

Don't ban them. Make the wording OEM only or removal.

 

Eliminates wacky awesome aftermarket systems. Doesn't hinder people that want to keep functional OEM ABS. BAM

FYI, we would certainly never ban OEM ABS for Time Trial, and we do want to continue to keep the rules for TT and the associated race classes completely

interchangeable. It has worked out very good for the drivers and for both TT and the PT and ST race series.

[Emmanuel B.]

Being one of those pestering Greg for the last few months for ST4, my initial thoughts are as follows and subject to improvement based on input from others.

 

ST4 should be a true extension of ST system with a few additional Modification factors along the following lines:

 

Tires:

Group current PT tires instead of just Non-DOT vs DOT-R. Example:

[A9] (-0.X)

[A1+A2] (-0.X)

[A3+A4+A5+A6] (+0)

[A7+A8] (+0.X)

 

Suspension/Chassis:

Relocation of suspension mounting points (-0.X)

Increased track width >4" (-0.X)

 

Aero:

Flat bottom/belly tray (-0.X)

Front fascia/air dam, Splitter, Canards (-0.X)

Wing, Diffuser, Vertical Panels (-0.X)

Front Windshield (-0.X)

[daytonars4]

ST4 would be a natural migration for GTS1/2 if the ratio makes that happen. 12 to 1 unfortunately would be a stretch. A typical GTS1/2 car is an E36. You expect around 240whp. The standard build is around 2900lbs loaded. For M cars it works just fine and is at the edge of the limit running completely strung out. For non M cars they would be so underpowered it just won't work since cutting sufficient weight is either not possible or too costly. 12.5 to 1 or 13 to 1 would work better if the e36's are a potential target.

 

A mod factor for OEM ABS is a terrible idea. 2015 was my first year of racing. I didn't have ABS and neither did a friend of mine. First race weekend after comp school he wrecks out while leading the race and takes out 2 other cars with him bc he locked up. If you add aN ABS penalty it promotes people removing it which is in my opinion creating a safety issue. If you want to add a mod for aftermarket ABS that would be reasonable.

 

Considering it's a lower powered class aero becomes less beneficial, not more. As you will see with the top GTS1 cars, they don't run any aero bc drag exceeds the benefit of the additional downforce. Therefore making the factor for aero higher in ST4 than you would for ST3 etc doesn't make sense bc the benefit is actually less. I actually started the year in GTS2 with all the fancy aero like diveplanes etc., but by Nationals I had reduced my wing angle and removed diveplanes which resulted in a PR.

 

You can add a mod factor for people with engines over x rpm to help reduce the benefit of a high strung motor. So for example, if your declared dyno shows a redline over 7500? rpm, .x mod.

 

 

Lawrence Gibson

Midatlantic

e36 M3 S54

GTS2

[PaulB#51]

I am all for this if we can keep the tires in proportion to the weight of the car.

I don't want to see a 2250 lbs, FI miata on 315's, with aero.

To keep costs down punish aero, punish over extra large tires based on weight.

Since we assume 12:1lbs to pwr.

How do we distinguish between various platforms since now we are taking power to weight out of the current PT base classing guide.

What about a chassis modifier.

You start with a Nissan Sentra you have a different modifyer the e36 m3.

Rank the cars 1-5.

One end of the spectrum are known great handling chassis, the other end are known crappy handlimg straight axle cars, ect...to help keep cost down.

 

Regards,

PaulB

[Brian L.]

I would like to see some restriction on tires and width for ST4. Eliminating non-DOT tires all together seems reasonable, keeps all the arguments about dot vs. non-DOT from even happening in the first place.

 

I don't think we should see any wide bodies or fender flares in ST4, maybe a max wheel width of 9" or something like that.

 

Restricting tire size and type should help with increasing the lap time gap between classes as well to help discourage out of class racing.

 

I might also catch some flack for this, but I say keep non production cars out of ST4 to simplify the rules on tire size. Keeping the class attracting similarly weighted cars will help keep the rules simple with balancing performance. This class should be be the cheapest way to go ST racing, if you have enough money for big fender flares and slicks, fancy non production tube frame cars with sequential gear boxes, than go play in the higher classes .

[Dysenpham]

Yes ST4/TT4 should just be a lower division of ST3/TT3, meaning the same mod factors and Avg WHP apply but to varying degrees. The same "red thread" should be woven within the aero rules giving "OEM aero" credit mod factor. Just be careful when it comes to rules that will cause some major rebuilds from folks already coming from other NASA classes.

[bpanther]

I might also catch some flack for this, but I say keep non production cars out of ST4 to simplify the rules on tire size. Keeping the class attracting similarly weighted cars will help keep the rules simple with balancing performance. This class should be be the cheapest way to go ST racing, if you have enough money for big fender flares and slicks, fancy non production tube frame cars with sequential gear boxes, than go play in the higher classes .

 

Hard thing to nail down, but maybe it makes sense. On the other hand, my non production ex-GTA tube frame car was put together for $8k. We've got an $80k 370Z in PTB here in Rocky Mountain (it was at champs at Laguna).

 

I am really trying to keep the cost of this car under $10k to show you can have a fast fun, yet still competitive, purpose built racecar w/o breaking the bank. I need cams, injectors and new throttle body to get it up to my new maximum HP with the 2016 formula. That would push it over that limit, but not by much.

 

Brian - you buy me that set of cams/heads and I'll stay in ST3 with it.

[hispanicpanic]

Being one of those pestering Greg for the last few months for ST4, my initial thoughts are as follows and subject to improvement based on input from others.

 

ST4 should be a true extension of ST system with a few additional Modification factors along the following lines:

 

Tires:

Group current PT tires instead of just Non-DOT vs DOT-R. Example:

[A9] (-0.X)

[A1+A2] (-0.X)

[A3+A4+A5+A6] (+0)

[A7+A8] (+0.X)

 

Suspension/Chassis:

Relocation of suspension mounting points (-0.X)

Increased track width >4" (-0.X)

 

Aero:

Flat bottom/belly tray (-0.X)

Front fascia/air dam, Splitter, Canards (-0.X)

Wing, Diffuser, Vertical Panels (-0.X)

Front Windshield (-0.X)

 

 

 

I think nickel and diming mods like this could prove usefull, but at the same time, aren't the TT class rules supposed to be simple?

 

Perhaps limiting non-OEM aero to 3 inch splitters as viewed from vertical, no elements past the rear bumper, some very basic restrictions on non-oem aero to prevent things from going wild. Maintaining the +.4 mod factor seems reasonable as well.

 

 

While we're on the topic of rules, modern automatic transmissions are pretty darn good. Almost as good as an OEM DCT type transmission, and many times better than a manual. It makes no sense to penalize OEM DCT transmissions while leaving automatics free. Either add the .2 modification to automatics, or remove the .2 penalty for OEM DCT's. Non-OEM sequentials and things i think are penalized properly. Maybe slightly too much, but the purpose of penalizing is to discourage, so its probably fine the way it is.

 

Also, now that average powers are considered, i think you seriously need to reconsider the points for rotaries and engines of specific displacement and such. With an average power consideration, there's no need to consider how the power is made.

[hispanicpanic]

Also forgot to add, people are mentioning restricting tire sizes. I think tire sizes should be 100% open, but place modification factors on classes of tire compounds. Penalize A7's and slicks the same, penalize R7's and anything with a published treadwear of 50 and below slightly less, Give back points for tires between 60-120 treadwear, and give even more points for tires of 130+ treadwear. If you want to limit the cash spent in classes, the easiest way to do that is by giving points back to those who wish to be competitive in less than professional budgets.

 

Example, 1 set of yokohama AD08-R in 295/30/18 is $1500. This set of tires lasted 8 track weekends, at $187 per weekend. I additionally did 8,000 DD miles on them driving to/from the track and on weekend joyrides/autocrosses. They had the same amount of grip for 7 track weekends, and began to fall off towards the end of the 7th. They still had tread so i did 1 more weekend. Contrast that to a set of A7's in the same size, and it's about $900 per weekend. Contrast that to NT01's and its about $375 per weekend, twice as much as my AD08-R's.

 

Tire sizes is dependant too much on the vehicle and it would be unfair to force a 4000 lb sedan to run on 245's while the miata's are on the same rubber.

[Emmanuel B.]

Perhaps limiting non-OEM aero to 3 inch splitters as viewed from vertical, no elements past the rear bumper, some very basic restrictions on non-oem aero to prevent things from going wild. Maintaining the +.4 mod factor seems reasonable as well.

I believe we're on the same page. My personal opinion is that non-OEM aero is a broad spectrum. A bolt dealer upgrade wing doesn't provide the same benefit as a $2k Good Aero wing. The guy with a keen interest in playing with aero should however be allowed to work on a full splitter + flat bottom + diffuser + wing. It should just come at a penalty that removes the unfair advantage created vs the guy who just buys a cheap aftermarket wing to help with some oversteer because he had to ditch a lot of weight in the rear to meet the new power limit. Just some basic restrictions like what you mentioned, etc so one doesn't have to develop or buy a lot of aero to match the guy who can spend.

 

I think tire sizes should be 100% open, but place modification factors on classes of tire compounds. Penalize A7's and slicks the same, penalize R7's and anything with a published treadwear of 50 and below slightly less, Give back points for tires between 60-120 treadwear, and give even more points for tires of 130+ treadwear. If you want to limit the cash spent in classes, the easiest way to do that is by giving points back to those who wish to be competitive in less than professional budgets.

I agree with this as well as you can see from my grouping. I should probably update the variables to X and Y to show the difference. I thought about tire widths as well. I feel the current 245 or less, 275 or less, and greater than 275 are too broad a spectrum. Perhaps a factor for 225 or less, 255 or less, and greater than that. I say 225 because a 205 can be stretched on a 9" wheel for nearly the same lateral grip as a 225.

[ILIKETODRIVE]

Also forgot to add, people are mentioning restricting tire sizes. I think tire sizes should be 100% open, but place modification factors on classes of tire compounds. Penalize A7's and slicks the same, penalize R7's and anything with a published treadwear of 50 and below slightly less, Give back points for tires between 60-120 treadwear, and give even more points for tires of 130+ treadwear.

I'm on the same page as you with my tire hypothetical:

 

TT4/ST4: add an adjustment for A tires (A.1 and A.2) from non-A tires, as well as keeping the adjustment for slicks (non-DOT tires)

https://nasa-assets.s3.amazonaws.com/document/document/457/TT__B-F__Car_Classification_Form_2015--v12.1--1-15-15.pdf

 

TT4/ST4 doesn't stray too far from TT3/ST3.

 

Tire sizes is dependant too much on the vehicle and it would be unfair to force a 4000 lb sedan to run on 245's while the miata's are on the same rubber.

Here's where I think everyone can win:

 

Add to TT4/ST4 through TT6/ST6 a size-to-weight table that has a smaller window as you move down in classes.

 

TT4/ST4 allows really light cars a lot of leeway with how big they can go and heavy cars no restrictions.

Edited December 9, 2015 by Guest

[Emmanuel B.]

Updated my initial thoughts to v0.1

ST4 should be a true extension of ST system with a few additional Modification factors along the following lines:

 

Tires:

Group current PT tires instead of just Non-DOT vs DOT-R. Example:

[A9] (-0.X)

[A1+A2] (-0.Y)

[A3+A4+A5+A6] (+0)

[A7+A8] (+0.Z)

 

Greater than 225 (-0.X)

Greater than 255 (-0.Y)

 

Suspension/Chassis:

Relocation of suspension mounting points (-0.X)

Increased track width >4" (-0.X)

 

Aero:

OEM non BTM aero (-0.X)

Non-OEM Aero (-0.Y)

Removal of Front Windshield (-0.Z)

[daytonars4]

Different cars have the ability to fit different size tires, so a flare rule wouldn't be fair. A Porsche 944/968 can easily fit 285's without flares, yet an E36 needs flares to even run 245's (I know bc I now run A7 245's and they rub even with banging out my fenders). So the mod should just be focused on tire size. An A7 is not a slick. I love my A7's but the grip is certainly not equal to the slicks I run in HPDE's. An A7 is 1 second a lap faster at VIR than an R7 so clearly you could put a factor for that. Or people could simply choose the A vs the R on their own? Even in GTS with the known gap people still choose the R bc it has a longer life cycle and in a 45 minute race, should result in faster laps toward the end. So why eliminate that ability for racers to strategize? If there's a penalty for an A, considering the end of race falloff in lap time you are basically double penalizing them. So I'd so no penalty there but there should be a delta vs someone running a Toyo. At this power level I'm not sure if it's reasonable for someone to expect to be competitive on a non-BFG/Hoosier etc tire. ST5/6 seems the more natural spot for that. On a BFG/Hoosier at VIR you are looking at 95-100mph in turn 10. On a toyo if you hit 85-90 I'd clap for you.

 

IMO in the 12 to 13 to 1 ratio range a person should expect aero on their car. I look at the GTS classes to understand the impact of aero and tires. In GTS1 none of the top guys run aero bc it's detrimental. That's an 18.5 to 1 class. In GTS2 we all run aero but at the "mid level." That's a 14.5 to 1 ratio. In GTS3 everyone runs substantial aero, that's a 11 to 1 class. You will also notice that none of the top guys are running slicks in GTS1-3. In GTS3 it results in a 1lb per whp penalty. So it would be safe to say that racers do not believe the penalty justifies the benefit. In in the higher GTS classes they do run slcisk bc the penalty is only .5. So keeping the same penalty of 1 to 1 for ST4 would be logical or you can slightly reduce it. I think ST5 and 6 sould be where the major aero penalties start to come into play. You can basically look at Spec 46 now to see what having a 12.5 to 13 to 1 looks like without aero. Those cars slide all over the place and it's a completely different driving experience from what you get in a more stable and planted GTS car with aero. Whereas Spec 30 is much slower so they don't slide around as much without aero. I enojy having a car that's easy to keep under me.

 

A DCT and PDK absolutely need a penalty, which we don't have in GTS. .2 seems reasonable. A sequential should have a very large penalty since the goal should be to keep the big builds out of this class. So .5 maybe for sequential.

 

Lawrence Gibson

Midatlantic GTS2

E36 S54

[Emmanuel B.]

(And for those that are immediately going to jump to UGH NO A7s AND AUTO-X COMPOUNDS?! WUT A JOKE! there are plenty of fast tires in A.3 so get over it)

I thought about that. There isn't a noticeable difference in cost for a set of A7 vs R7 (I've checked 6 sizes on tirerack) so I don't really think there's a huge cost saving. I think we should penalize the performance advantage accordingly, but I don't think it should be eliminated.

[ILIKETODRIVE]

Tyres!

Edited December 9, 2015 by Guest

[Emmanuel B.]

I thought about that. There isn't a noticeable difference in cost for a set of A7 vs R7 (I've checked 6 sizes on tirerack) so I don't really think there's a huge cost saving. I think we should penalize the performance advantage accordingly, but I don't think it should be eliminated.

It's not just about cost; it's about entry into the series. Low PTW cars that crossover (from Spec classes and the like) typically don't run A tires. If you're adamant about running A tires or having them available, step your butt up to TT5/ST5. Just like if you say Y DO THEY GET HELP 4 NO AERO in TT3/ST3; step your butt up to TT2/ST2.

 

The faster race compound tires will be penalized accordingly vs slower race compound tires and "street" tires.

Not sure I entirely follow your post. The thread title suggests ST4 Rules Proposal. How is that relevant?

 

Edit: It appears you're referring to eliminating them for ST6. Disregard my comment. I don't have an opinion here nor there on that subject. The focus right now is on ST4.

[daytonars4]

Spec racers for the most part will race in .... Spec classes. I think the Spec46 and GTS2 comparison to help with the factors is a great fundamental approach. GTS2 and Spec 46 run very similar lap times. So you have a no aero/toyo/(higher end but non-remote suspension) car on par with a DOT/aero car/remote suspension car. Spec 46 has about a 1.5lb per whp advantage and run similar size tires. Spec 46 blows away GTS2 on the straights and the inverse happens in the corners. So the combination of the penalty for aero, remote suspension, and tires should fundamentally make these cars equal in a ST4 class. Therefore the penalty for the combination of aero+tire compound+remotes should not exceed 1.5 for this scenario. How you weight that penalty between aero/tires/suspension is a guessing game unless someone does trial testing.