Rule Proposal - Drop Torque From the Power Calculation

[ssmith]

GTS has an opaque method (currently https://drivenasa.com/wp-content/uploads/gts-calculator/21calcjs.js) for calculating "power" but it is clear torque plays a factor.  I propose that torque be dropped completely from the calculation as whatever performance benefit it provides is better determined by analyzing the shape of the power curve, which already happens.

A moving object has energy related to the mass and velocity as KE=0.5*m*v^2.  Energy is simply work (aka power) over time.  We can remove time by taking the derivative of both sides w.r.t. time which yields P=0.5*m*2*v^(2-1)*a=m*v*a.  Or, power to weight aka P/m=v*a.  At no point does torque, transmission ratios, gear ratios, tire diameter (including how it changes with temperature) come into play.

Historically people have used torque as an indicator of performance.  If you're just told peak HP and peak torque from a motor, then it can give a sense of the shape of the power curve.  However given that we have to enter power from the dyno every 500 RPM, the calculator knows the shape of the power curve already.

The rule basically penalizes people that don't have high revving engines such as an S54 or S65.  A car that can make full power from 5500-8000 RPM with a 4.10:1 differential will behave the same performance as an engine that makes full power from 4125-6000 RPM with a 3.08:1 differential, but the latter will have more torque (at the engine as a Dynojet calculates, not the wheels) yielding a penalty in the GTS calculator.

The penalty for high torque is so high that it actually makes sense to get a sequential transmission for GTS.  That would use a narrow power band (never needing low RPM power) and have very fast shifts.  In GTS Challenge this results in a paltry 0.2 adjustment to the power to weight ratio.  In comparison, a motor that makes 210whp but 267 ft lbs torque takes an effectively penalty of 1.6 (in GTS3).

My name is Scott Smith, I'm an ST4 driver in Norcal region.  I am not a current GTS driver.  In the Norcal region it basically doesn't exist, and ST does not penalize torque (it does take into account how many dyno data points to use based on peak RPM, thus it does take the shape of the power curve into account).  I am proposing this rule because some day I would like to drive east and try some tracks, and I notice that ST4 is nonexistent outside of California, so my choice would be to either run ST3 or one of the GTS classes.  I would like to make sure my car would be reasonably competitive if that happened.

[daytonars4]

ST not factoring torque is why the Camaro’s put 3-4 car lengths on BMW’s on every straight, every start, and every restart. Come to MA for a weekend and you will have a better understanding of why the torque being including is mandatory. Or you can even message me and we can figure out how to get some videos to you. It’s almost comical. Part of the reason we are moving our 10+ car field in ST3 back to GTS3 is due to this. 

[Tansar_Motorsports]

I agree with the OP.

In order to calculate acceleration based on torque, you would need to include RPM, overall gear ratio, and tire diameter, in order to get to the actual force transmitted between the tire and the pavement.  These factors vary significantly from car to car, making torque a bad metric by which to balance multicar classes.

With power, on the other hand, you can calculate your acceleration with nothing than power and weight:

From a mathematical standpoint, TRQ does not matter.  Power determines acceleration.
Too many people have been indoctrinated by the idea that "TRQ wins races".
Mathematically, TRQ is an instantaneous value, it has no time component.  Meanwhile, 1 HP  = 750 Watts.  A Watt is 1 Joule per second.  Joule is the standard unit of energy.  Therefore, if we multiply our power by time, we can calculate how much energy we have added to our vehicle.  In this case, kinetic energy.  Velocity is proportional to kinetic energy (KE = 1/2 M * V^2).  Therefore, our change in velocity (acceleration) is directly proportional to Power * time.

example: accelerating at 200 HP for 10 seconds adds 200*10*750 = 1.5 million Joules of energy to our car.  Starting from an initial speed of zero, in a car that weights 1000 KG,  the velocity would increase to 54 m/s = 194 km/h = 120 mph.  Note, this example ignores wind resistance and rolling resistance.
Therefore, we achieve an average acceleration of 54m/s / 10 seconds = 5.4m/s^2
Look at that, we calculated acceleration without needing to consider TRQ, RPM, or gear ratio!
Power/weight ratio is the correct way to balance a multi-car class, because it eliminates differences in available gear ratios and max RPM.

 

@daytonars4
Camaros pull lengths on you out of corners because they have more low end power than you do.  So as long as the average PWR calculation takes into account a wide enough RPM range, then it should balance out overall.  If your car was equal weight to a camaro, and they have more low end power for initial acceleration, then you would have more top end power, to catch up later down the straight.
In reality, Camaro / mustang are much heavier than other cars, so they have more power, so they should beat other cars on the straight, and lose in the corners...

[ssmith]

1 hour ago, daytonars4 said:

ST not factoring torque is why the Camaro’s put 3-4 car lengths on BMW’s on every straight, every start, and every restart. Come to MA for a weekend and you will have a better understanding of why the torque being including is mandatory. Or you can even message me and we can figure out how to get some videos to you. It’s almost comical. Part of the reason we are moving our 10+ car field in ST3 back to GTS3 is due to this. 

With all due respect, the science does not back that statement up.  "Correlation is not causation."

Looking at the recent results, it looks like Jeffrey Lewis in a Camaro beat Steven Laderman in an M3 at VIR: https://racehero.io/events/nasa-ma-vir-octoberfast-2022/results/1073743701#show:detailed-info-overall-175

Jeffrey makes more than 350rwhp from 4300RPM to 6000RPM.  That's 28% of the rev range in question.  Here is the dyno chart for Jeffrey: https://drive.google.com/file/d/1W7rmdr8HMPeHa-LgBa1-URkqK60Azw3I/view

Steven makes more than 300rwhp from 6500RPM to 8100RPM.  That's less than 20% of the rev range.  Here is the dyno chart for Steven: https://drive.google.com/file/d/1aYYCJi4OuScCu4D3OdVrRuXVdXO1EUxP/view

Given the typical BMW manual ratios of 1.66 for 3rd, 1.24 for 4th, and 1.00 for 5th, that means he'll drop to 6050RPM on 3->4 and 6532RPM on 4->5.  Thus Steven's shifts *have* to be perfect, he always has to be in the right gear in every corner, and even after all that, his shift from 3->4 will put him out of his power band.  Ignoring reliability and cost issues, raising the rev limiter to 8700RPM (assuming the same power level) would "solve" the 3->4 shift and give more breathing room in deciding between 4th and 5th gear, and notably would NOT increase engine torque at all.

And even after all that, VIR is a power track (compared to what we have on the west coast).  At 140mph (as I saw multiple times per lap in some YouTube videos), aero drag gets pretty big.  Those two cars may start at the same power/weight ratio, but once you subtract aero drag, you get (power-drag)/weight or (power/weight - drag/weight).  Well, assuming power/weight is the same, then the car with the lowest drag/weight wins.  One way is to have less drag.  The other way is to have more weight.

Here's a video of Jake Latham at NASA ST2 Champs at Laguna Seca.  The car to his right is an S54 powered BMW E36, Ian Barberi.  The two cars weigh about the same.

Jake has a wide flat power band (320rwhp from 4300RPM-7000RPM), tons of torque (410 ft lbs), and a sequential.
Ian has a peaky power band (>350rwhp 7500-8400RPM, >320rwhp 6500-8400RPM), no torque (250 ft lbs), and a manual (and thus is allowed more power due to ST rules).

Ian loses out at tip in due to having less power at that RPM (note Jake started the race at 4200RPM, just a hair shy of peak power, giving him a long stretch of acceleration before having to shift).
You see Ian gain it back as he reaches his peak RPM but then lose due to the shift, and you see him gain it back by the end of the straight due to having more power (despite having less torque).  You can see all the science play out in that one start, perfectly explained by the power used.

 

[daytonars4]

1 hour ago, ssmith said:

With all due respect, the science does not back that statement up.  "Correlation is not causation."

Looking at the recent results, it looks like Jeffrey Lewis in a Camaro beat Steven Laderman in an M3 at VIR: https://racehero.io/events/nasa-ma-vir-octoberfast-2022/results/1073743701#show:detailed-info-overall-175

Jeffrey makes more than 350rwhp from 4300RPM to 6000RPM.  That's 28% of the rev range in question.  Here is the dyno chart for Jeffrey: https://drive.google.com/file/d/1W7rmdr8HMPeHa-LgBa1-URkqK60Azw3I/view

Steven makes more than 300rwhp from 6500RPM to 8100RPM.  That's less than 20% of the rev range.  Here is the dyno chart for Steven: https://drive.google.com/file/d/1aYYCJi4OuScCu4D3OdVrRuXVdXO1EUxP/view

Given the typical BMW manual ratios of 1.66 for 3rd, 1.24 for 4th, and 1.00 for 5th, that means he'll drop to 6050RPM on 3->4 and 6532RPM on 4->5.  Thus Steven's shifts *have* to be perfect, he always has to be in the right gear in every corner, and even after all that, his shift from 3->4 will put him out of his power band.  Ignoring reliability and cost issues, raising the rev limiter to 8700RPM (assuming the same power level) would "solve" the 3->4 shift and give more breathing room in deciding between 4th and 5th gear, and notably would NOT increase engine torque at all.

And even after all that, VIR is a power track (compared to what we have on the west coast).  At 140mph (as I saw multiple times per lap in some YouTube videos), aero drag gets pretty big.  Those two cars may start at the same power/weight ratio, but once you subtract aero drag, you get (power-drag)/weight or (power/weight - drag/weight).  Well, assuming power/weight is the same, then the car with the lowest drag/weight wins.  One way is to have less drag.  The other way is to have more weight.

Here's a video of Jake Latham at NASA ST2 Champs at Laguna Seca.  The car to his right is an S54 powered BMW E36, Ian Barberi.  The two cars weigh about the same.

Jake has a wide flat power band (320rwhp from 4300RPM-7000RPM), tons of torque (410 ft lbs), and a sequential.
Ian has a peaky power band (>350rwhp 7500-8400RPM, >320rwhp 6500-8400RPM), no torque (250 ft lbs), and a manual (and thus is allowed more power due to ST rules).

Ian loses out at tip in due to having less power at that RPM (note Jake started the race at 4200RPM, just a hair shy of peak power, giving him a long stretch of acceleration before having to shift).
You see Ian gain it back as he reaches his peak RPM but then lose due to the shift, and you see him gain it back by the end of the straight due to having more power (despite having less torque).  You can see all the science play out in that one start, perfectly explained by the power used.

 

Jeff is making 430wtq at 4500rpm. He short shifts around 6k rpm. So how can you claim torque doesn’t matter when he spends a majority of his time below 6000rpm? We can just agree to disagree on that one. As I said, I don’t support this rule change and neither will anyone in Midatlantic. 
 

What engine are you running in your car that is motivating you to ask GTS to remove the torque calculation? Let’s have some transparency here. There’s a reason that guys have swapped LS’s into their BMW’s. And it’s not Bc it’s cheaper since by the time you add a required drysump it’s actually more expensive. Torque matters…

[daytonars4]

Just did my research @ssmith and now I know why you want to change this rule. You are making 210hp/302tq! Yea, I'm gonna pass on that. We have no interest in having guys with power curves like that in GTS2. What I find funny is that the people who always claim that torque doesn't matter are the same exact people who are running massive torque. If torque doesn't matter it's very easy for you to detune the engine to reduce it. There is no benefit to have a sequential in GTS2 where power curves are fairly flat anyway. We have PDK's, sequentials, and manuals in GTS2 in midatlantic already. All the lap records are from the manual cars. If you don't want to reduce the torque on your engine it's obviously bc you think there is some benefit to having it. Just insane for you to even try to convince us otherwise. Having gone from a 210hp/210tq S54 tune to 210hp/230tq I can say definitively that acceleration improved. Same car same driver. So I can only imagine how much further low end acceleration would improve with 210hp/300tq.

The ST calculator is a joke so using that as a reference does not really "prove" anything. Just to make my point, my ratio in ST3 is 9.4 with an S54. Even with 10.0 ratio in GTS3 my race weight would be lower in GTS. The ST rules and calculator reward low revving high torque engines excessively and penalize high revving engines. This probably made sense back in the day when American cars sucked and there was a need to handicap German cars. But things have changed....

[int2str]

@daytonars4that's some weird gate keeping...
@ssmith and @Tansar_Motorsportshave explained the math and science. And your reply is "I'm gonna pass on that"?

There's nothing transparent about the current GTS calculator and there is no benefit in making it this complicated. Given that I may have to class my car in GTS soon, I also support dropping this part of the calculation.

If you think torque is such a special super power, how come Scott isn't consistently winning? Let me assure you he's one of the fastest drivers I've ever met and his car is certainly on point. He has a 4 cylinder turbo. Your gatekeeping and these rules just prevent innovation like he did for no real reason. Why would you not want more competition in your class?

NASA champs in ST4 have been pretty much exclusively won by de-tuned S54's in all recent history. So clearly, that mythical Camaro, Mustang or Scott's torque monster have not caused any issues in ST4. Even at COTA and Daytona, where the Mustang's and Vette's probably had their best chance, S54's took it.

Oh, and if you don't understand why Scott "needs" the torque in a power/weight limited class, look no further than this formula:
   HP = TQ x RPM/5252 

So yeah, I support the rule change request.

[ssmith]

1 hour ago, daytonars4 said:

Just did my research @ssmith and now I know why you want to change this rule. You are making 210hp/302tq! Yea, I'm gonna pass on that. We have no interest in having guys with power curves like that in GTS2. What I find funny is that the people who always claim that torque doesn't matter are the same exact people who are running massive torque. If torque doesn't matter it's very easy for you to detune the engine to reduce it. There is no benefit to have a sequential in GTS2 where power curves are fairly flat anyway. We have PDK's, sequentials, and manuals in GTS2 in midatlantic already. All the lap records are from the manual cars. If you don't want to reduce the torque on your engine it's obviously bc you think there is some benefit to having it. Just insane for you to even try to convince us otherwise. Having gone from a 210hp/210tq S54 tune to 210hp/230tq I can say definitively that acceleration improved. Same car same driver. So I can only imagine how much further low end acceleration would improve with 210hp/300tq.

The ST calculator is a joke so using that as a reference does not really "prove" anything. Just to make my point, my ratio in ST3 is 9.4 with an S54. Even with 10.0 ratio in GTS3 my race weight would be lower in GTS. The ST rules and calculator reward low revving high torque engines excessively and penalize high revving engines. This probably made sense back in the day when American cars sucked and there was a need to handicap German cars. But things have changed....

You haven't actually provided any data to back up your claim that torque is why the Camaros are winning.  You just keep restating it like it is fact.  Do you have any acceleration logs from cars that make your point?  As you said in another thread, "So once again, let’s show some real data to support this concept. Not just thoughts and feelings."

Here's some acceleration data from Buttonwillow raceway.  It was hot, I was short shifting to keep temps at bay, though for these two laps the temps are pretty comparable.  The acceleration is basically the same regardless of what gear I was in, even though the engine makes more torque at lower RPM.  You've seen my dyno chart, go ahead and look at the numbers.

I've raced against detuned S54 and uncorked S52 with my N20; some cars shift more than others, some cars have more torque than others, but in the end of the day our acceleration was the same until it came to aero drag.  I have data, video, and math backing up my statements.

 

[daytonars4]

Answer this simple question @ssmith. You claim there is no benefit to torque. So if that's the case why is your car tuned for 210hp 300tq instead of 210hp 230tq. You/your tuner can easily accomplish the lower torque. Since there is no benefit according to your logic, why bother doing it?.... This is really simple. Since torque doesn't matter you can have a GTS2 tune so you can fit the GTS rules. Then you can have your ST4 tune for the ST rules. Simple as that. I run GTS2 with 1 tune and GTS3/ST3 with another. Why are we pretending this is complicated? You have made your position clear, you want to eliminate the torque rule. I understand ... I oppose. GL

[ssmith]

13 minutes ago, daytonars4 said:

Answer this simple question @ssmith. You claim there is no benefit to torque. So if that's the case why is your car tuned for 210hp 300tq instead of 210hp 230tq. You/your tuner can easily accomplish the lower torque. Since there is no benefit according to your logic, why bother doing it?.... This is really simple. Since torque doesn't matter you can have a GTS2 tune so you can fit the GTS rules. Then you can have your ST4 tune for the ST rules. Simple as that. I run GTS2 with 1 tune and GTS3/ST3 with another. Why are we pretending this is complicated? You have made your position clear, you want to eliminate the torque rule. I understand ... I oppose. GL

I don't need to explain the advantage of my power curve, though I have proven that it isn't due to torque.  You might be able to figure it out if you go back and reread my posts and try to understand the math behind them instead of holding onto your preconceived notions about "torque" being the reason.

Please make a logical argument on why I'm wrong.  Show data, show math, show video.  Refute the acceleration data I showed in different gears.  Refute the calculus on the kinetic energy of a moving object.  Refute the video I posted of a high torque Vette being out accelerated by a low torque BMW.

Do something other than ignoring everything that's been posted and posting whataboutisms.

[daytonars4]

You claim there’s no benefit yet won’t simply retune your car to meet the rules of the class. That’s says it all. Thanks for your time….

[ssmith]

1 hour ago, daytonars4 said:

You claim there’s no benefit yet won’t simply retune your car to meet the rules of the class. That’s says it all. Thanks for your time….

You literally ignored the first two sentences of my last post.  Are you just trolling at this point?

[daytonars4]

There is 1 easy way to “prove” that torque doesn’t matter

-Take AIM data of your car with the 210whp/302wtq tune. 

-Take AIM data with your car tuned for 210whp/230wtq. 
 

Post the overlay here for our review. If the acceleration is the same you have now proven torque doesn’t matter. Now I don’t expect you to actually do this. But it’s frankly a straight forward way to “prove” it. But once again, if there was no benefit to being tuned to 302tq you  wouldn’t do it or spend time and energy arguing for a rule change. So I won’t bother going back and forth with you anymore. You can see if anyone who races in GTS wants to support this rule change. Likely going to be tough to find a “majority” of people to support it.?‍♂️

[ssmith]

5 minutes ago, daytonars4 said:

There is 1 easy way to “prove” that torque doesn’t matter

-Take AIM data of your car with the 210whp/302wtq tune. 

-Take AIM data with your car tuned for 210whp/230wtq. 
 

Post the overlay here for our review. If the acceleration is the same you have now proven torque doesn’t matter. Now I don’t expect you to actually do this. But it’s frankly a straight forward way to “prove” it. But once again, if there was no benefit to being tuned to 302tq you  wouldn’t do it or spend time and energy arguing for a rule change. So I won’t bother going back and forth with you anymore. You can see if anyone who races in GTS wants to support this rule change. Likely going to be tough to find a “majority” of people to support it.?‍♂️

 

I posted data showing the acceleration in a gear making lots of engine torque but the same power is the same as acceleration in a gear making less torque.  I posted it for your review and you've simply ignored it because it doesn't fit your worldview that torque matters.

As I've said, my power curve has an advantage, but torque isn't it.  I could recreate the power curve I want with a high strung unreliable motor; it would cost a lot of money but make less torque and have the same on track performance.  I won't do that test for you; that's what would be required to do a true apples to apples test.  What you're asking isn't a true "only change one variable" test, and the fact you don't understand that is why you'll never understand why some cars are faster than others on track.

[daytonars4]

Changing 1 variable (a tune adjustment which can be done for probably $300) to perform a test according to you “isn’t a true only change one variable test.” Understood …  I’ll stay in the decline camp. Guess we’ll see if anyone else who currently races in GTS agrees with a change like this. 
 

Are you aware that SRO has added BOP to reduce torque on some of the forced induction cars to balance them out with NA cars? If torque doesn’t matter its hard for me understand why they would pursue that approach. Also I have been around M2CS Factory cars. I know that the BOP power sticks significantly reduce torque. It is common knowledge to get custom tunes that boost torque but maintain hp in order to improve pace. This is what the top teams in AER/WRL and ST3 guys do with their M2’s. I literally had one guy tell me “the low torque BOP tune is trash.” So they go from 320hp/320tq to 320hp/380tq or something around that. But either way, it’s above my level of understanding. I’m sure since you appear to be experienced on “what makes cars fast” you will be able to figure out a solution within the GTS rules …

Edited October 25, 2022 by daytonars4

[Tansar_Motorsports]

This conversation is hopeless.

For the record I drive a rotary RX8 (non turbo), so I dont even know what torque is...

 

To simplify everything that has been said.  Basic science & math, as well as actual in car data, prove that a low rpm/high torque motor making 300 HP when it exits a corner at 4000 RPM, and a high rpm/low torque motor making 300 HP when it exits a corner at 6000 RPM will have the exact same acceleration.  Because torque doesn't matter.  

 

Now, yes, if a high torque motor and a low torque motor both exit the corner, and both are down at 3000 rpm at corner exit, then the high torque motor is going to walk away.  Why?  Because it is making more POWER at 3000 RPM than the low torque motor.  Because HP = TQ x RPM/5252

[ssmith]

On 10/24/2022 at 10:57 PM, daytonars4 said:

Are you aware that SRO has added BOP to reduce torque on some of the forced induction cars to balance them out with NA cars? If torque doesn’t matter its hard for me understand why they would pursue that approach. Also I have been around M2CS Factory cars. I know that the BOP power sticks significantly reduce torque. It is common knowledge to get custom tunes that boost torque but maintain hp in order to improve pace. This is what the top teams in AER/WRL and ST3 guys do with their M2’s. I literally had one guy tell me “the low torque BOP tune is trash.” So they go from 320hp/320tq to 320hp/380tq or something around that. But either way, it’s above my level of understanding. I’m sure since you appear to be experienced on “what makes cars fast” you will be able to figure out a solution within the GTS rules …

Because what they're really doing is changing the shape of the power curve.  When you are already have a motor, changing torque means changing the power curve.  When you're deciding to build a motor, you can target whatever power curve you want at whatever torque you want - they can be independent since you can treat the third variable - RPM - as a dependent variable.  SRO isn't about to change the RPM the cars are built for.  And this is the crux of my complaint, that one should not have to build a high $$$ motor to get the power curve one wants AND a low torque reading, as it's the power curve that affects performance, not the peak torque number.  The current GTS rules favor S54/S65 engines.  It isn't that ST favors torque monsters.  In fact ST uses a smaller percentage of the rev range on lower RPM cars than it does on high RPM cars, thus allowing high RPM cars to use more datapoints to bring down their average.

To quote my original post, with some bolding:

On 10/18/2022 at 11:59 AM, ssmith said:

I propose that torque be dropped completely from the calculation as whatever performance benefit it provides is better determined by analyzing the shape of the power curve, which already happens.

...

Historically people have used torque as an indicator of performance.  If you're just told peak HP and peak torque from a motor, then it can give a sense of the shape of the power curve.  However given that we have to enter power from the dyno every 500 RPM, the calculator knows the shape of the power curve already.

Go back and look at the AiM data I posted.  Red line represents a motor that revs from 3750 RPM to 5250 RPM, making 201-210rwhp and 285 ft lbs torque.  Blue line represents a motor that revs from 4750RPM to 6700RPM, making 200-207rwhp and 228 ft lbs torque.  25% more torque!  The laps were 2 minutes apart - weather conditions were the same, track conditions were the same, time pressures were the same, coolant temp was the same.  How is this not proof enough for you that torque is not the factor to look at when determining acceleration?  Unless you think the parasitic loss of 5th gear is some 25% compared to 1:1 4th gear (I don't, I think it's a couple percent, which is why I think the red line is actually a little slower than the blue line - it works out to about a 7hp loss over the 10 seconds).

 

[daytonars4]

@Tansar_Motorsportsis spot on. This conversation is hopeless Bc you aren’t likely to see support from current GTS racers to get on board with this ?.. You are also spot on when you compare 2 identical engines, 1 tuned for massive torque and 1 tuned with no torque. The car with more torque will accelerate faster out of corners. Literally the only point I’ve been trying to make here with the experiment I suggested be run. The engines in GTS2 such as S50/52 and even detuned S54’s all have fairly flat power curves. So the last thing people with these engines want is for someone to show up with a 210hp/300tq with a 7k redline to compete against their 210hp/215tq S50/52/54. I say this knowing it’s the S50/52 7k redline engines with all the track records in my region. 
 

Now if you say you want to run a 210hp/300tq engine in GTS3/4 where peaky power curves are the norm, then maybe there’s some discussion around torque limits. But based on what I see of this engine it’s unlikely to be competitive  in GTS3 so not really sure what else to say. But on that note, ✌️

[ssmith]

45 minutes ago, daytonars4 said:

You are also spot on when you compare 2 identical engines, 1 tuned for massive torque and 1 tuned with no torque. The car with more torque will accelerate faster out of corners. Literally the only point I’ve been trying to make here with the experiment I suggested be run.

I have the results of that experiment, you just keep ignoring it.  285 ft lbs vs 228 ft lbs torque.  As I said:

19 hours ago, ssmith said:

Go back and look at the AiM data I posted.  Red line represents a motor that revs from 3750 RPM to 5250 RPM, making 201-210rwhp and 285 ft lbs torque.  Blue line represents a motor that revs from 4750RPM to 6700RPM, making 200-207rwhp and 228 ft lbs torque.  25% more torque!  The laps were 2 minutes apart - weather conditions were the same, track conditions were the same, time pressures were the same, coolant temp was the same.  How is this not proof enough for you that torque is not the factor to look at when determining acceleration?  Unless you think the parasitic loss of 5th gear is some 25% compared to 1:1 4th gear (I don't, I think it's a couple percent, which is why I think the red line is actually a little slower than the blue line - it works out to about a 7hp loss over the 10 seconds).

 

But then you say:

47 minutes ago, daytonars4 said:

The engines in GTS2 such as S50/52 and even detuned S54’s all have fairly flat power curves. So the last thing people with these engines want is for someone to show up with a 210hp/300tq with a 7k redline to compete against their 210hp/215tq S50/52/54.

...

 Now if you say you want to run a 210hp/300tq engine in GTS3/4 where peaky power curves are the norm, then maybe there’s some discussion around torque limits. But based on what I see of this engine it’s unlikely to be competitive  in GTS3 so not really sure what else to say. But on that note, ✌️

So to summarize:  You don't want me to race my flat power curve against other cars with flat power curves because that's not fair.  Instead I should race my flat power curve car in class where peaky power curves are the norm.  Have you heard the term cognitive dissonance?

 

 

[daytonars4]

@ssmithwhat’s obvious is that you want to change the rules so that at corner exit when these S50/52 cars are at 4K rpm with low tq/low hp, you will have an advantage at high tq=hp that’s already similar to your peak hp. This is actually what the torque rule is meant to prevent. By having 300tq you can have over 3k rpm of peak hp while these other cars only have 1500-2k rpm of peak hp. What you gain is essentially the equivalent of having a seq which allows you to stay in the peak power range without taking any mod for having a seq. Trying to convince other people that this doesn’t matter looks pretty silly from the outside…

Edited October 27, 2022 by daytonars4

[ssmith]

2 minutes ago, daytonars4 said:

@ssmithwhat’s obvious is that you want to change the rules so that at corner exit when these S50/52 cars are at 4K rpm with low tq/low hp, you will have an advantage at high tq=hp that’s already similar to your peak hp. This is actually what the torque rule is meant to prevent. By having 300tq you can have over 3k rpm of peak hp while these other cars only have 1500-2k rpm of peak hp. Trying to convince other people that this doesn’t matter looks pretty silly from the outside…

Great I'm glad we've gotten to this point.  This is exactly the point I was trying to make with my first post.  To quote:

On 10/18/2022 at 11:59 AM, ssmith said:

I propose that torque be dropped completely from the calculation as whatever performance benefit it provides is better determined by analyzing the shape of the power curve, which already happens.

If you don't want flat power curves, then add a rule to ban flat power curves - by measuring power.  As it is, you can have an S54 that makes 210rwhp over a 3200RPM range (5000RPM-8200RPM).  What apparently is not allowed is making 210rwhp from 4000RPM-7000RPM.  That's why I say the rules favor S54/S65 over low revving motors, as low revving motors get hit by the magic 90% of anatomy and beer pints compared to my daughter's favorite animal.  That's what I'm trying to equalize - you should have opportunity to make any legal power curve with any motor.  Right now you can't.

[daytonars4]

2 minutes ago, ssmith said:

Great I'm glad we've gotten to this point.  This is exactly the point I was trying to make with my first post.  To quote:

If you don't want flat power curves, then add a rule to ban flat power curves - by measuring power.  As it is, you can have an S54 that makes 210rwhp over a 3200RPM range (5000RPM-8200RPM).  What apparently is not allowed is making 210rwhp from 4000RPM-7000RPM.  That's why I say the rules favor S54/S65 over low revving motors, as low revving motors get hit by the magic 90% of anatomy and beer pints compared to my daughter's favorite animal.  That's what I'm trying to equalize - you should have opportunity to make any legal power curve with any motor.  Right now you can't.

S50/52 are flat power curves without tuning. All they are doing is putting in restrictor plates which flattens it. So now you essentially propose a ban on the tune that 70% of the cars in GTS2 naturally have. What value does killing the class have?  
 

You further aren’t making any sense Bc you and I both know that you can create a power curve with a turbo engine to be identical to an S54 in GTS2. So this isn’t a question of not being allowed to use a motor that’s legal to create a legal power curve. This is a matter of you wanting to use a legal motor to create an illegal power curve. And expect others to agree to change the rules to allow you to do that. This whole thread is just ridiculous at this point. 
 

The rules do not favor an S54 in GTS2. We’ve had S52 and S54’s in my region in GTS2 since at least 2014. S54 has no track records here. No S54’s had a top 3 laptime at Nationals here in 2015 (There were 2 in the field including mine). And when we review the data S50/52 seem to have better acceleration than S54’s. I can’t explain why Bc I certainly assumed the S54 would be better. But in real life sometimes things don’t work out the way they seem like they should in the lab. 

At least now we have gotten to the heart of the matter. Bottom line is you want to join the class with the ability to have peak hp for 3k rpm while no NA car in class is capable of accomplishing that. Congratulations for just being the typical racer out there who tried to get rules changed to just benefit themselves at the detriment of the class…

[ssmith]

17 minutes ago, daytonars4 said:

You further aren’t making any sense Bc you and I both know that you can create a power curve with a turbo engine to be identical to an S54 in GTS2. So this isn’t a question of not being allowed to use a motor that’s legal to create a legal power curve. This is a matter of you wanting to use a legal motor to create an illegal power curve. And expect others to agree to change the rules to allow you to do that. This whole thread is just ridiculous at this point.

I cannot create the same power curve as an S54 because I cannot rev to 8000+RPM.  Here is an example S54 power curve, at least on the west coast:

https://drive.google.com/file/d/1yHSvkkJSguznAdOCB90bfe-lAPgVgSJ9/view

229rwhp, 250 ft lbs torque, "only" 8050RPM rev limiter.  Over 220rwhp from 4750 to 8000RPM.  90% of 250 is 225, so he does not hit the torque limit, but he's awfully close.

Since my revlimit is around 7000, I have to shift the whole curve down by 1000RPM.  If I had over 220rwhp from 3750 to 7000RPM, I would have 308 ft lbs torque, which would require me to run as if I had a 277rwhp car.

Since the rules do not outlaw a 3250RPM wide flat power band, and an S54 can run that power band but other motors that don't rev as high cannot run that power band, then the rules favor S54/S65.  If you're saying a 3250RPM wide flat power band is not an advantage (since S50/S52 rule in GTS2), then why is it a problem if I am also allowed to run a 3250RPM wide flat power band?  Either it's an advantage or not, and either it's allowed or not.  But it shouldn't be allowed for some motors and not for others.

[daytonars4]

If this is your concern then a productive rules convo would be to suggest that we limit rpm in GTS2 to 7000 or 7500rpm. The solution is not to just allow turbo cars to now game the system to a level that makes every S50/52 in class obsolete. I absolutely see what you mean here. BUT having had 2 race cars with S54’s I can say I haven’t seen a car with a S54 with a tune like that “outperform” the S50/52. As a matter of fact in Midatlantic we ditched the flat S54 tune for something else that has proved to be more effective based on data.
 

Do you have data that shows that an S54 with this power curve has an acceleration advantage over an S52? Should be pretty easy to do a data overlay for us to review. My S54 detune showed better acceleration than my S54 flat tune. I want to get out of this world of theory you are trying to use and get to the real world. Let’s see if in the real world with the current GTS2 rules, is there a “problem” that needs to be fixed. The last thing anyone wants to do is come up for a solution for a problem that doesn’t exist, which then creates a real problem.

Edited October 28, 2022 by daytonars4

[ssmith]

9 minutes ago, daytonars4 said:

My S54 detune showed better acceleration than my S54 flat tune.

Before I respond to the rest, can you clarify this sentence?  Maybe I'm using a different definition but to me "detune" means not running a full power tune, and "flat tune" means a power band with the same horsepower as much as possible.  Usually "flat tunes" are "detunes" but maybe I'm missing some implied meaning?