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Technical Bulletin: Avg HP Calculations--All ST & TT 3-11-22


Greg G.
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Posted (edited)

Technical Bulletin 3-11-22

Avg HP Calculations—Applies to all ST and TT Rules-- effective immediately

The following revision of ST Rules Section 7.2 will take effect immediately.  New wording is in blue font below.  Sections 7.2.1, 7.2.3, and 7.2.3 shall remain unchanged at this time.  A new ST/TT Dyno Certification Form will be posted shortly that includes these changes as well as the wording that was revised in the ST Rules earlier this year. 

Competitors not using Avg HP do not need to update their ST/TT classing submissions. 

All competitors using Avg HP that have already submitted 2022 ST/TT compliance documentation need to review their Dyno data export table and determine if this rule revision affects the data points used for their Avg HP calculations.  If there are no changes in the data points used, or if the competitor is using a HP number equal to or greater than Max HP for their ST/TT classing, nothing needs to be done.  However, if this rule revision results in different data points being used to calculate the Avg HP, the competitor needs to edit their current ST/TT classing submission, upload the data export table with all 250 RPM data points circled or highlighted, and submit a new page 3 of the Dyno Certification Form. 

All competitors getting new pre-competition Dyno testing should use the new Dyno Certification Form (revised 3/22).  All competitors using Avg HP that are revising their Avg HP should update their page 3 of the Dyno Certification Form and their data export table. 



7.2 Average Horsepower Calculation

Any competitor may choose to use Maximum Horsepower instead of Average Horsepower
at any time.


The number used for calculating the Adjusted Wt/HP Ratio will be a calculated average giving a better approximation of the maximum horsepower available over the range of usable RPM. For pre-competition testing, the Dyno test with the highest maximum horsepower will be used to calculate this average (not an average of the three Dyno runs) as follows (all horsepower numbers will be rounded to the nearest whole number before any calculations):

Avg HP = Average HP calculated and used in the Adjusted Wt/HP Ratio
Max HP = Maximum horsepower shown on the data export

On the Dyno 50 RPM data export numeric RPM/HP table printout, circle (or highlight) all HP data points in 250 RPM increments above and below the Max HP.  The highest seven (7) of those data points will then be used with the formulas below.  Data points showing on the graph/table after the physical rev limiter has been hit or after the Dyno brake has been actuated will not be used. 

Any Dyno curve resulting in aberrant data points that would otherwise be included in the Avg HP calculation that are not consistent with the usable power band or flat tune power band can be rejected by the Race Director/TT Director at their discretion, and the Maximum HP will be used to classify the vehicle.

 

(If any of the above data points at higher RPM than Max HP RPM do not exist due to maximum
RPM, then those potential data points will not be used in the calculation of Avg HP.)

7.2.1 For vehicles with a maximum RPM greater than 7000 rpm:
The seven (7) highest data points of the above seven (7) will be used in the calculation below:
Avg HP = Max HP +(sum of the seven highest data points)/8

7.2.2 For vehicles with a maximum RPM between 6000-7000 rpm:
The five (5) highest data points of the above seven (7) will be used in the calculation below:
Avg HP = Max HP +(sum of the five highest data points)/6

7.2.3 For vehicles with a maximum RPM less than 6000 rpm and all Forced Induction
vehicles:
The three (3) highest data points of the above seven (7) will be used in the calculation below:
Avg HP = Max HP +(sum of the three highest data points)/4

Edited by Greg G.
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To: All ST and TT competitors
Hi Folks, I hope that the start of your season is going well. We came upon an issue this past weekend with the Avg HP calculation method, and although we really don’t like mid-season rules revisions as much as most of you, we decided that a revision of this rule was necessary to avoid further misunderstanding and potential controversy. In doing so, we are following rule number 2, Intent, of both the ST and TT Rules.
 
Although we have had the Avg HP rule since 2016, and wrote the rule to try and decrease the amount of work that competitors need to do to calculate the Avg HP, we had a competitor attempt to gain an unfair advantage using the current rule. While it is controversial whether this was a violation of the TT Rules, at this point, the best course is to revise the rule to avoid future issues. We have posted a Technical Bulletin on the NASA Community in the ST section, and we have updated the ST-TT Dyno Certification Form.
 
The short version is that instead of using a range of 2000 RPM above and below the Max HP to find data points to use for calculating Avg HP, competitors will now use the entire Dyno graph/table to find the highest 250 RPM increment data points to use for the Avg HP calculation. The technical bulletin outlines who will need to update their ST-TT classing submissions.
 
Thanks, and have a great season!
 
Greg Greenbaum
NASA National ST & TT Director
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12 minutes ago, Brian Clarke said:

I’ve read this a bunch of times what are we trying to stop here?

Brian, see above.  If you haven't looked at the TT group on FB lately, check out the post with the Dyno graph.

We are stopping someone from attempting to gain a huge unfair advantage using the Avg HP rule.  Also, we are cleaning up the loophole of obtaining a slight advantage by having a flat tune with a very long RPM range that has higher data points further than 2000 rpm from the Max HP. 

This will have no effect on those who are not using Avg HP, or those not manipulating their Dyno tunes, or even the majority that are manipulating their Dyno tunes.

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I got removed from the TT group with no explanation or notice actually.  Can’t even read it.   I mean I pay my dues!!

Edited by Brian Clarke
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Brian,

Any competitor that doesn't like the decision by a Race Director or TT Director can appeal that decision by the usual methods. 

But, they are being directed on what they should be looking for.

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1 minute ago, Greg G. said:

Brian,

Any competitor that doesn't like the decision by a Race Director or TT Director can appeal that decision by the usual methods. 

But, they are being directed on what they should be looking for.

As a competitor I want to know what your looking for.

 Do you have an example to show? 

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13 minutes ago, Brian Clarke said:

As a competitor I want to know what your looking for.

 Do you have an example to show? 

The last rule allows the Race Director or TT Director to delete aberrant data points that are creating an unfair advantage by the competitor attempting to manipulate the system.  An example of this would be for a competitor to have a flat HP curve for a usable 1750 RPM range and dump power before (and after) that range by 100+ HP in order to have an aberrant data point 100 HP less to help bring the average down, but use a transmission capable of staying in that 1750 RPM range all of the time.

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4 hours ago, Brian Clarke said:

I got removed from the TT group with no explanation or notice actually.  Can’t even read it.   I mean I pay my dues!!

You've been unblocked. Play nice.

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If I am reading it correctly ----------- my "RPM at Max HP" is 7300. Rev limit is 7800 rpm. So, does "Horsepower at 250 rpm increments above/below Max HP from the 50 RPM increment table" mean using 250 rpm increments? If so, is the "50 rpm increment table" referring to the layout of the chart on the print out? (I am "assuming" so, but want clarity.)

In rereading this, I am afraid that some with think I am too dim to be able to use Velcro, but I gave up "assuming" quite some time ago.

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The recent issue in question was legal to the rules, and a known loophole for years.   None of my clients/competitors have the extra 400hp required to take advantage of this loophole

 

Complex rules lead complex “cheats”!    
 

      Enforcement relies on local series’ directors to understand and examine submissions: that continues to be the weak link in the regions around me.   There continues to be cars with missing data (usually the 50rpm sheet)

 

 

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7 hours ago, Bob Bubxaum said:

If I am reading it correctly ----------- my "RPM at Max HP" is 7300. Rev limit is 7800 rpm. So, does "Horsepower at 250 rpm increments above/below Max HP from the 50 RPM increment table" mean using 250 rpm increments? If so, is the "50 rpm increment table" referring to the layout of the chart on the print out? (I am "assuming" so, but want clarity.)

In rereading this, I am afraid that some with think I am too dim to be able to use Velcro, but I gave up "assuming" quite some time ago.

Hi Bob,

Yes, the 50 RPM refers to the setting used to output the data on the table you print out.  Then, choose those 250 rpm increments as you stated.  So 7550, 7800, 7050, etc.

We use the 50 RPM table because the program gives different numbers if we choose to look at 250 RPM output table.

So, bottom line is, you are approved and certified to use Velcro. 🤣

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