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New SM7.5 Tire First Majors HST Race Performace

- - - - - SM7.5 Tire 2020 Buttonwillow HST

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#1
RWP80000

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https://1drv.ms/b/s!...8I0qjA?e=g8RvQm

 

Click on the link above to see a PDF summary of results from the 2020 Buttonwillow HST Event for the first official use of the SM7.5 tire in competition.

 

A quick summary of the results are as follows;

  • There were 19 SM entries in the Buttonwillow event with somewhere between 7 and 9 competitors ran the SM7.5 in competition.
  • Average times between the current SM7 vs SM7.5 for the top five competitors over four "on-track" sessions were close to the same.
  • The fastest SM7 competitor averaged 2:05.530 sec. Lap Times for the four sessions while the SM7.5 averaged 2:05.594 for 4 users.
  • Fastest Qualifying time went to the SM7.5 tire with it being the only tire to break into sub 2:05.00 lap times (two competitors).
  • The fastest qualifying time was 2:04.724 sec's for the SM7.5 vs 2:05.058 sec's (3rd fastest) for the fastest SM7 qualifying time.

Out of 6 potential race Podium positions, five went to the SM7.5 tire including both race wins, the remaining 3rd Place podium going to the SM7. 

 

The performance capability of the SM7.5 seemed to be consistent with conditions over the 4 "on-track" sessions and did not show any sign that there was a "flyer" lap related to any particular Heat Cycle.

 

In general the wear surface of the SM7.5 appeared even and flat but their was one situation where there was tire surface irregularities that looked like a thin skin of rubber had separated from the tread surface.  The Hoosier tire rep said that this issue was due to tire mold release compound getting on the uncured tread rubber as it was inserted into the mold and that this irregularity would go away as the tire wore down.  I will be sending this tire back to Hoosier for engineering evaluation.  We did run this set of tires on the Saturday race but we moved the tire from the most heavily loaded RR position and put it on the least loaded LF position. 

 

Also, as a result of this condition we elected to run a second set of SM7.5 sticker tires in the second qualifying session as a precaution.  Under the new Tire Limiting Program proposal, we would have lost our first qualifying time and would have had to start from the rear for the 2nd qualifying session since we used a second set of tires.  We could have used a single replacement instead and kept the first set of times and started in the earned 3rd place Qual 2 start position.  Ironically, at last years Buttonwillow HST, we also had a tire quality problem where we had a 7 to 9 inch long tread edge separation that was attributed to improper curing in the mold.  This also resulted in our use of a second set of sticker tires at this event in 2019 due to a tire irregularity.

 

Rich Powers

SM 145


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#2
Jim Drago

Jim Drago

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https://1drv.ms/b/s!...8I0qjA?e=g8RvQm
 
Click on the link above to see a PDF summary of results from the 2020 Buttonwillow HST Event for the first official use of the SM7.5 tire in competition.
 
A quick summary of the results are as follows;

  • There were 19 SM entries in the Buttonwillow event with somewhere between 7 and 9 competitors ran the SM7.5 in competition.
  • Average times between the current SM7 vs SM7.5 for the top five competitors over four "on-track" sessions were close to the same.
  • The fastest SM7 competitor averaged 2:05.530 sec. Lap Times for the four sessions while the SM7.5 averaged 2:05.594 for 4 users.
  • Fastest Qualifying time went to the SM7.5 tire with it being the only tire to break into sub 2:05.00 lap times (two competitors).
  • The fastest qualifying time was 2:04.724 sec's for the SM7.5 vs 2:05.058 sec's (3rd fastest) for the fastest SM7 qualifying time.
Out of 6 potential race Podium positions, five went to the SM7.5 tire including both race wins, the remaining 3rd Place podium going to the SM7. 
 
The performance capability of the SM7.5 seemed to be consistent with conditions over the 4 "on-track" sessions and did not show any sign that there was a "flyer" lap related to any particular Heat Cycle.
 
In general the wear surface of the SM7.5 appeared even and flat but their was one situation where there was tire surface irregularities that looked like a thin skin of rubber had separated from the tread surface.  The Hoosier tire rep said that this issue was due to tire mold release compound getting on the uncured tread rubber as it was inserted into the mold and that this irregularity would go away as the tire wore down.  I will be sending this tire back to Hoosier for engineering evaluation.  We did run this set of tires on the Saturday race but we moved the tire from the most heavily loaded RR position and put it on the least loaded LF position. 
 

 
Rich Powers
SM 145

 


Rich,
Thanks for the info. Hard to really make heads or tails, but that's a good synopsis. Did anyone run SM7 back to back with sm7.5?
Did anyone race sm7.5s with more than 3 sessions on them?
 

https://1drv.ms/b/s!...8I0qjA?e=g8RvQm
 
 
Also, as a result of this condition we elected to run a second set of SM7.5 sticker tires in the second qualifying session as a precaution.  Under the new Tire Limiting Program proposal, we would have lost our first qualifying time and would have had to start from the rear for the 2nd qualifying session since we used a second set of tires.  We could have used a single replacement instead and kept the first set of times and started in the earned 3rd place Qual 2 start position. 
Rich Powers
SM 145

Rich
That was a choice you made.  If you were under the tire limiting rule, you likely would have just switched the one tire with NO penalty and no performance issues unless you were so concerned with starting at the front for qualifying?  I would have just switched the one, 100%.  IMO, you went to stickers because you could with no penalty and it was a better race option. Exactly what the tire limiting proposal would stop. I look at that as a positive! Also, who cares that you needed to start at the back in qualifying?  Don't get me wrong, I would have done the exact same thing.  


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NASA Champs Winner - NASA Champs Winner Hoosier Super Tour points Champion - Hoosier Super Tour points Champion ARRC Champion - Won the ARRC Race in a Spec Miata Series Champ - Won a points based series in a Spec Miata BFG Supertour Winner - Majors Winner - Circuit of the Americas Winner - We have a Winnah! - Won their 1st race... Congratulations! June Sprints winner  - June Sprints winner June Sprints winner  - June Sprints winner June Sprints winner  - June Sprints winner June Sprints winner  - June Sprints winner SCCA National Champion - Won SCCA Runoffs at Road America SCCA National Champion - Won SCCA Runoffs at Road America

#3
RWP80000

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Rich,
Thanks for the info. Hard to really make heads or tails, but that's a good synopsis. Did anyone run SM7 back to back with sm7.5?
Did anyone race sm7.5s with more than 3 sessions on them?

 

Jim, Yes there is data in there on back to back SM7 vs SM7.5.  If you look at the first practice, everyone was on SM7's.  Then for the first qualifying, half of the Top 6 were on SM7.5 and half on SM7's. That comparison shows the SM7.5 to have about a 1/4 sec advantage over the SM7. Then you can look at Dakota Dickerson who was on SM7 in first Qual. session and then went to SM7.5 stickers for Qual 2, winning the Pole with a 2:04.724 sec time, which was 1.694 seconds faster than his previous qualifying time on SM7's.

 

As an aside, Littlehale was on SM7 tires for all qualifying and race sessions.  I did show a "(?)" for his heat cycles only because I did not personally observe that he was on Stickers for the first Q-session but he had told me he was going to qualify on SM7 stickers but I did not personally observe if he used stickers in Q1, Q2 or both. 

 

As far as anyone running SM7.5 for more than 3 HC's, I can say positive that J. Rutter ran on SM7.5 for all four of qualifying and race sessions.  I do not believe he introduced a second set of SM7.5 during the event.  Also, I do not know for sure what Nick Leverone did but I know he was on SM7.5 for the 4 qualifying and race sessions.  I cannot say positively that he did not introduce a 2nd set but I do not think so which would mean that he also put 4 sessions on his SM7.5's.  It should also be noted that he ran the fastest Sunday race lap.

 

 

 

 

Rich

That was a choice you made.  If you were under the tire limiting rule, you likely would have just switched the one tire with NO penalty and no performance issues unless you were so concerned with starting at the front for qualifying?  I would have just switched the one, 100%.  IMO, you went to stickers because you could with no penalty and it was a better race option. Exactly what the tire limiting proposal would stop. I look at that as a positive! Also, who cares that you needed to start at the back in qualifying?  Don't get me wrong, I would have done the exact same thing.  It seems like you went out of your way to point out a potential negative that I don't see as a negative and a situation that would be easily addressed with no penalties?

 

Jim, I agree 100% that we would have not made the same choice on running a second set if the Tire Limiting program was in place and that the position from which we started our qualifying session had noting to do with our final qualifying result at this event.  However, at other events with high number of entries on tracks where drafting is an important factor, starting position can be a factor especially were you need a good partner and when being a "independent" means having to work with those around you at the back.

 

I do have concerns on the effort to police and enforce this type of rule when it is difficult to even get people to self report when they have "incidental" contact on the track.

 

I have been giving a lot of thought to this program from the aspect of how to best implement it and one of my thoughts is that we need to make it as un-intrusive as we can.  The thought I have on this is that instead of all this "loss of times and going to the back of the pack" we take a different approach and make it so all penalties are implemented in effect "post race".

By this I mean that you would only capture the tire ID's for the first 10 cars during each qualifying session and the top 20 cars for the race ( as "points" are awarded through at most the top 20).  Then, the penalties for anyone not being on the same tires as used in the first Qualifying session, would be to reduce the Tire Contingency Award as well as the Conference and HST Points awarded all by HALF in the next Race(s) with any fractional tire or point being rounded down to the next full integer.  

 

Under this proposal there would be no loss of qualifying or race positions allowing the racing to take place based on actual competitive contests without draconian last place starts in large fields which only serve to frustrate anyone who may have been "taken out" through no fault of their own.  The Contingency and Point penalties would be significant enough to discourage putting on "sticker" tires indiscriminately but would also allow those that have an incident, whether through their own fault or not, to replace damaged tires if necessary while continuing to participate at from an appropriate performance position while being penalized AFTER the competition for the excessive use of tires by the implementation of the loss of both significantly reduced Tire Contingency, Conference and HST Points awards. This would be easier to implement and only affects those finishing in the positions for receiving awards as needing to be verified at the end of 2nd qualifying and each race.

 

Rich Powers



#4
Jim Drago

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Jim, Yes there is data in there on back to back SM7 vs SM7.5.  If you look at the first practice, everyone was on SM7's.  Then for the first qualifying, half of the Top 6 were on SM7.5 and half on SM7's. That comparison shows the SM7.5 to have about a 1/4 sec advantage over the SM7. Then you can look at Dakota Dickerson who was on SM7 in first Qual. session and then went to SM7.5 stickers for Qual 2, winning the Pole with a 2:04.724 sec time, which was 1.694 seconds faster than his previous qualifying time on SM7's.

 

As an aside, Littlehale was on SM7 tires for all qualifying and race sessions.  I did show a "(?)" for his heat cycles only because I did not personally observe that he was on Stickers for the first Q-session but he had told me he was going to qualify on SM7 stickers but I did not personally observe if he used stickers in Q1, Q2 or both. 

 

As far as anyone running SM7.5 for more than 3 HC's, I can say positive that J. Rutter ran on SM7.5 for all four qualifying and two race sessions.  I do not believe he introduced a second set of SM7.5 during the event.  Also, I do not know for sure what Nick Leverone did but I know he was on SM7.5 for the 4 qualifying and race sessions.  I cannot say positively that he did not introduce a 2nd set but I do not think so which would mean that he also put 4 sessions on his SM7.5's.  It should also be noted that he ran the fastest Sunday race lap.

 

 

 

 

 

Jim, I agree 100% that we would have not made the same choice on running a second set if the Tire Limiting program was in place and that the position from which we started our qualifying session had noting to do with our final qualifying result at this event.  However, at other events with high number of entries on tracks where drafting is an important factor, starting position can be a factor especially were you need a good partner and when being a "independent" means having to work with those around you at the back.

 

I do have concerns on the effort to police and enforce this type of rule when it is difficult to even get people to self report when they have "incidental" contact on the track.

 

I have been giving a lot of thought to this program from the aspect of how to best implement it and one of my thoughts is that we need to make it as un-intrusive as we can.  The thought I have on this is that instead of all this "loss of times and going to the back of the pack" we take a different approach and make it so all penalties are implemented in effect "post race".

By this I mean that you would only capture the tire ID's for the first 10 cars during each qualifying session and the top 20 cars for the race ( as "points" are awarded through at most the top 20).  Then, the penalties for anyone not being on the same tires as used in the first Qualifying session, would be to reduce the Tire Contingency Award as well as the Conference and HST Points awarded all by HALF in the next Race(s) with any fractional tire or point being rounded down to the next full integer.  

 

Under this proposal there would be no loss of qualifying or race positions allowing the racing to take place based on actual competitive contests without draconian last place starts in large fields which only serve to frustrate anyone who may have been "taken out" through no fault of their own.  The Contingency and Point penalties would be significant enough to discourage putting on "sticker" tires indiscriminately but would also allow those that have an incident, whether through their own fault or not, to replace damaged tires if necessary while continuing to participate at from an appropriate performance position while being penalized AFTER the competition for the excessive use of tires by the implementation of the loss of both significantly reduced Tire Contingency, Conference and HST Points awards. This would be easier to implement and only affects those finishing in the positions for receiving awards as needing to be verified at the end of 2nd qualifying and each race.

 

Rich Powers

 

 

Probably not the thread.. So I will keep it short.  change "tire" to "restrictor plate"  they rarely check 20 restrictor, nor would they need to check 20 tires.  the same 4-6-8- they pull in after whichever session is the only cars they check. instead of checking for scca stickers, they can check tires. 

 

And for the 100th time. If a tire is damaged at no fault of your own, you have a case to replace the tire w/o penalty.  Keep your video rolling. 

Way too many holes in what you proposed there, at that proposed there, I would prefer scrapping it as the juice is not worth the squeeze. 

 

If it was a sprints win or something that mattered, I would forgo the contingency and put the third set on if I thought I needed it, just like I did last year and lost :) 


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NASA Champs Winner - NASA Champs Winner Hoosier Super Tour points Champion - Hoosier Super Tour points Champion ARRC Champion - Won the ARRC Race in a Spec Miata Series Champ - Won a points based series in a Spec Miata BFG Supertour Winner - Majors Winner - Circuit of the Americas Winner - We have a Winnah! - Won their 1st race... Congratulations! June Sprints winner  - June Sprints winner June Sprints winner  - June Sprints winner June Sprints winner  - June Sprints winner June Sprints winner  - June Sprints winner SCCA National Champion - Won SCCA Runoffs at Road America SCCA National Champion - Won SCCA Runoffs at Road America




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