Best Track Times in a GT4
#903
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Randy P at Willow Springs:
#905
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Thunderhill 5 mile course - 3:09.965 - 15 Sep 2017 - Hoosier R7 - Suspension mods
Thanks to MoTeC USA I managed to save my data from Friday when I had troubles with recording accurate lap times. Naturally, it was user error, but I was able to recover the sessions I thought were lost. As I suspected, I was a wee bit faster in the morning sessions on the 5 mile west side bypass configuration, dipping into the nines.
Thanks to MoTeC USA I managed to save my data from Friday when I had troubles with recording accurate lap times. Naturally, it was user error, but I was able to recover the sessions I thought were lost. As I suspected, I was a wee bit faster in the morning sessions on the 5 mile west side bypass configuration, dipping into the nines.
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#908
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My first thought is that so long as the tires and mods are disclosed, we should keep just one score card.
However, it is true that mods such as full slicks give the driver a substantial advantage. It could be argued that it takes it from a street car to a race-only car.
What if we agreed on a time-penalty for cars outfitted with non-DOT tires?
It would still allow the fastest drivers, many of which prefer to run slicks, to achieve top podium status.
Do you like this idea?
And, if so, how much faster in terms of percentage are slicks faster than the fastest DOT tires?
#909
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I hear you.
My first thought is that so long as the tires and mods are disclosed, we should keep just one score card.
However, it is true that mods such as full slicks give the driver a substantial advantage. It could be argued that it takes it from a street car to a race-only car.
What if we agreed on a time-penalty for cars outfitted with non-DOT tires?
It would still allow the fastest drivers, many of which prefer to run slicks, to achieve top podium status.
Do you like this idea?
And, if so, how much faster in terms of percentage are slicks faster than the fastest DOT tires?
My first thought is that so long as the tires and mods are disclosed, we should keep just one score card.
However, it is true that mods such as full slicks give the driver a substantial advantage. It could be argued that it takes it from a street car to a race-only car.
What if we agreed on a time-penalty for cars outfitted with non-DOT tires?
It would still allow the fastest drivers, many of which prefer to run slicks, to achieve top podium status.
Do you like this idea?
And, if so, how much faster in terms of percentage are slicks faster than the fastest DOT tires?
![Stick Out Tongue](https://rennlist.com/forums/images/smilies/tongue.gif)
More seriously, I think that there should just be one list and all mods should be included. Tires are the most easily understood mod which also makes the biggest difference so perhaps just a note should be added before the list saying that RE-71/Dunlop/MPSC2 are +0 seconds, while Hoosier/Pirelli slicks are +2 seconds adjustment on a 2 min track (1.66%). Because it's a percentage, you could have a different adjustment for each track (2 seconds at Thunderhill, 1.6 seconds at Laguna?) Leave the order by overall lap time, but one can do the math for oneself on how to compare the times.
#910
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Hoosier R7, which most people run, are in fact DOT tires. Hoosiers slicks are another level (Hoosier also makes the "Continental" slicks used in IMSA) and are comparable to Pirelli DH slicks, Michelin slicks are another level above. I agree with keeping one list with full disclosure of tires and mods. The biggest variable is the driver. I'm a big believer in data and looking at my "Fast" laps always reveals that several of my corners in the fast lap are "average".
#911
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I know a guy who ran a 1:38 at Road Atlanta last week... without a 3rd gear! ![EEK!](https://rennlist.com/forums/images/smilies/eek.gif)
So we should include mods and handicaps too.
![EEK!](https://rennlist.com/forums/images/smilies/eek.gif)
So we should include mods and handicaps too.
#912
Nordschleife Master
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Originally Posted by orthojoe
Another time to post driving in someone else's car. Lol.
I took the GT3 out out to thunderhill, but I brought up a set of GT4 wheels with 235/295 R7s mounted on them. My friend was nice enough to let me mount the wheels on her GT4 to let me do a break in run. I did 3 warm up laps, each lap 20 seconds faster, and on the 4th lap I gave it a go and then cooled back down. The one hot lap netted a new PB of 3:09.2 with 106F intake temps vs prior PB of 3:11.5 on RE71R and 80F intake temps. Will give the tires a real test in 2 weeks once the tires have 'cured'
https://youtu.be/XAc3kwP2Zjc
I took the GT3 out out to thunderhill, but I brought up a set of GT4 wheels with 235/295 R7s mounted on them. My friend was nice enough to let me mount the wheels on her GT4 to let me do a break in run. I did 3 warm up laps, each lap 20 seconds faster, and on the 4th lap I gave it a go and then cooled back down. The one hot lap netted a new PB of 3:09.2 with 106F intake temps vs prior PB of 3:11.5 on RE71R and 80F intake temps. Will give the tires a real test in 2 weeks once the tires have 'cured'
https://youtu.be/XAc3kwP2Zjc
In regards to the time list, it's too complicated to separate everything out. You're doing everyone a service by doing what you already do. To assign a specific time penalty would be very arbitrary. It's fine to leave it as is, but list tires and mods. We all know tires are the biggest factor when it comes to times. Ambient temps would be interesting to note as well
Last edited by orthojoe; 09-19-2017 at 10:27 PM.
#913
Nordschleife Master
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Looks like you accidentally shifted into 6th instead of 4th going into T1? Probably lost a tenth or 2 there. Exit speeds must be high enough with R7 where you need to shift into 5th at the end of the straight, or maybe it's smoother to bounce off the rev limited for 4th since your time in 5th is so short?
Is there still a light tap on the brake for T8 or just a lift?
Man, i really need to recalibrate myself to take advantage of these tires. When I go back to RE71R I need to be careful not to drive myself off the track!
Do you bother with the single break in heat cycle and let the tires sit for a week so they grip longer, or am I just wasting my time?
#914
Burning Brakes
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Originally Posted by orthojoe
Do you bother with the single break in heat cycle and let the tires sit for a week so they grip longer, or am I just wasting my time?
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
As someone who drives their car to and from the track, R7's, or other comparable or stickier tires really are not a good option for you. It's outright dangerous to drive those tires on the street.
BUT, if you decide to take the plunge, here's my .02 after many laps on R compound tires: IT DEPENDS. On so many different factors. Car weight and setup. Track surface. Ambient temperatures. Length of sessions. Driving style and skill. Etc.
Some people swear by proper heat cycling. Others say it doesn't matter. Neither case has been proven definitively.
What is known is that all R compounds and slicks are stickiest when they're new. You can be sure to get a few fantastic sessions from them and then performance will fade, more or less gradually. Most DE guys like you will get 15-20 sessions out of a set of R7's. But, at your level, and as someone who is always chasing lap times, you'd probably want to swap them out before they are completely worn out. On that point, I have never held on to a set of R7's until they've corded. Once I see my lap times dropping significantly I swap them for a fresh set. With this protocol I can more easily evaluate my own performance without having worn tires as an excuse.
Final comment, running stickier tires requires some setup changes. But they're worth it!
#915
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Joe, we all knew it was only a matter of time before the sticky tire dark side won you over. ![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
As someone who drives their car to and from the track, R7's, or other comparable or stickier tires really are not a good option for you. It's outright dangerous to drive those tires on the street.
BUT, if you decide to take the plunge, here's my .02 after many laps on R compound tires: IT DEPENDS. On so many different factors. Car weight and setup. Track surface. Ambient temperatures. Length of sessions. Driving style and skill. Etc.
Some people swear by proper heat cycling. Others say it doesn't matter. Neither case has been proven definitively.
What is known is that all R compounds and slicks are stickiest when they're new. You can be sure to get a few fantastic sessions from them and then performance will fade, more or less gradually. Most DE guys like you will get 15-20 sessions out of a set of R7's. But, at your level, and as someone who is always chasing lap times, you'd probably want to swap them out before they are completely worn out. On that point, I have never held on to a set of R7's until they've corded. Once I see my lap times dropping significantly I swap them for a fresh set. With this protocol I can more easily evaluate my own performance without having worn tires as an excuse.
Final comment, running stickier tires requires some setup changes. But they're worth it!
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
As someone who drives their car to and from the track, R7's, or other comparable or stickier tires really are not a good option for you. It's outright dangerous to drive those tires on the street.
BUT, if you decide to take the plunge, here's my .02 after many laps on R compound tires: IT DEPENDS. On so many different factors. Car weight and setup. Track surface. Ambient temperatures. Length of sessions. Driving style and skill. Etc.
Some people swear by proper heat cycling. Others say it doesn't matter. Neither case has been proven definitively.
What is known is that all R compounds and slicks are stickiest when they're new. You can be sure to get a few fantastic sessions from them and then performance will fade, more or less gradually. Most DE guys like you will get 15-20 sessions out of a set of R7's. But, at your level, and as someone who is always chasing lap times, you'd probably want to swap them out before they are completely worn out. On that point, I have never held on to a set of R7's until they've corded. Once I see my lap times dropping significantly I swap them for a fresh set. With this protocol I can more easily evaluate my own performance without having worn tires as an excuse.
Final comment, running stickier tires requires some setup changes. But they're worth it!
It'll be interesting to see how many 'good' sessions I get out of this set. That will determine whether or not I use them again. If its 15-20 sessions, that is not bad at all seeing as that is how much I get out of RE71R these days.