991 GT3 Track Lap Times
12-07-2015, 08:23 PM
#76
Rennlist Member
About 600 per front and 1000 per rear corner. No driver weight compensation yet.
If I haven't forgotten Sebring yet I should be able to get there. The car can certainly do it or better, but not sure if I will. So far only driven RS on tracks I never been to. It arrives Dec 23 in port, so hopefully a practice day before Winterfest to setup the car because the fender liners will go flying as-is.
12-08-2015, 07:15 AM
#77
3250 with half a tank? Plus my 250+doesn't help.
About 600 per front and 1000 per rear corner. No driver weight compensation yet.
If I haven't forgotten Sebring yet I should be able to get there. The car can certainly do it or better, but not sure if I will. So far only driven RS on tracks I never been to. It arrives Dec 23 in port, so hopefully a practice day before Winterfest to setup the car because the fender liners will go flying as-is.
About 600 per front and 1000 per rear corner. No driver weight compensation yet.
If I haven't forgotten Sebring yet I should be able to get there. The car can certainly do it or better, but not sure if I will. So far only driven RS on tracks I never been to. It arrives Dec 23 in port, so hopefully a practice day before Winterfest to setup the car because the fender liners will go flying as-is.
12-08-2015, 03:04 PM
#79
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Brainerd International Raceway
1:37.7 - 1:38.xx seen below
Michelin PSC2 - fresh set to start the day
79*F with a slight wind
Mods - GT3 cup bushings, GT3 Cup caliper studs, aggressive-street alignment, Akrapovic Evolution Race exhaust, EvoMS tune (completed post-trackday)
Figured my first post would be track-related.. Let's see some more times guys, it's a long winter!
1:37.7 - 1:38.xx seen below
Michelin PSC2 - fresh set to start the day
79*F with a slight wind
Mods - GT3 cup bushings, GT3 Cup caliper studs, aggressive-street alignment, Akrapovic Evolution Race exhaust, EvoMS tune (completed post-trackday)
Figured my first post would be track-related.. Let's see some more times guys, it's a long winter!
12-08-2015, 07:11 PM
#81
Rennlist Member
I started cold at 26 F and 25R. My hot pressures in my last session were 33 PSI all the way around But tire temperatures showed the center still hotter than the outside edge, so it's telling me I want hot pressure of probably 31 or 32 PSI. That's consistent with what I have read about Trofeo Rs
I struggled with rising hot psi's throughtout the weekend. I was afraid to start with such a low cold psi. My car is set up similar to yours ( an aggressive street set up) -2.1 deg. (f) -1.9 deg. (R) maximum I could achieve without shims and changing other suspension parts.
For clarification I was on the OEM PSC2's but experienced the same as you. I was starting with 26/27 psi cold , first lap and half spent waiting on pressure than a period of two laps with good grip, than the last few laps managing under steer and a loose rear end as the pressures would rise to 35/37. I was struggling trying to get mid 2:26's. Most laps (when there was a clean one) were upper 26's lower 27's. I can run high 26's in my 996 GT3 so needless to say I was a bit troubled by this as one would think a similarly driven 991 GT3 would be quicker than a similarly driven 996 GT3
Finally, after Keith Jensen (shared a garage with him) mentioned that he spoke to someone about starting with much lower pressures (perhaps it was you he spoke with) I started at 23/24.
Had to wait a little longer for the pressure to come up BUT I found the tires stayed underneath the car for the remainder of the session. A big improvement. I was able to click off 2:24/ 2:25 lap times much easier than the struggling I was doing earlier to squeak out 26's/27's.
By the end of the session I observed 31/33 f/r.
My plans are to eventually amend my alignment just as I saw you post earlier. I observed a good bit of shoulder wear, not horrible but I know it can be better with a little more neg. camber.
I am hoping that with a little suspension tweaking, better psi management, and more time with the car on circuit, some 2:23's will be acheivable. Perhaps I may have to move to the Trofeo R's for that as well. Time will tell.
12-09-2015, 01:13 PM
#82
Same findings here Keith, I was at COTA this weekend as well. This was my first time at COTA in my 991 GT3, 2nd time tracking the car altogether.
I struggled with rising hot psi's throughtout the weekend. I was afraid to start with such a low cold psi. My car is set up similar to yours ( an aggressive street set up) -2.1 deg. (f) -1.9 deg. (R) maximum I could achieve without shims and changing other suspension parts.
For clarification I was on the OEM PSC2's but experienced the same as you. I was starting with 26/27 psi cold , first lap and half spent waiting on pressure than a period of two laps with good grip, than the last few laps managing under steer and a loose rear end as the pressures would rise to 35/37. I was struggling trying to get mid 2:26's. Most laps (when there was a clean one) were upper 26's lower 27's. I can run high 26's in my 996 GT3 so needless to say I was a bit troubled by this as one would think a similarly driven 991 GT3 would be quicker than a similarly driven 996 GT3
Finally, after Keith Jensen (shared a garage with him) mentioned that he spoke to someone about starting with much lower pressures (perhaps it was you he spoke with) I started at 23/24.
Had to wait a little longer for the pressure to come up BUT I found the tires stayed underneath the car for the remainder of the session. A big improvement. I was able to click off 2:24/ 2:25 lap times much easier than the struggling I was doing earlier to squeak out 26's/27's.
By the end of the session I observed 31/33 f/r.
My plans are to eventually amend my alignment just as I saw you post earlier. I observed a good bit of shoulder wear, not horrible but I know it can be better with a little more neg. camber.
I am hoping that with a little suspension tweaking, better psi management, and more time with the car on circuit, some 2:23's will be acheivable. Perhaps I may have to move to the Trofeo R's for that as well. Time will tell.
I struggled with rising hot psi's throughtout the weekend. I was afraid to start with such a low cold psi. My car is set up similar to yours ( an aggressive street set up) -2.1 deg. (f) -1.9 deg. (R) maximum I could achieve without shims and changing other suspension parts.
For clarification I was on the OEM PSC2's but experienced the same as you. I was starting with 26/27 psi cold , first lap and half spent waiting on pressure than a period of two laps with good grip, than the last few laps managing under steer and a loose rear end as the pressures would rise to 35/37. I was struggling trying to get mid 2:26's. Most laps (when there was a clean one) were upper 26's lower 27's. I can run high 26's in my 996 GT3 so needless to say I was a bit troubled by this as one would think a similarly driven 991 GT3 would be quicker than a similarly driven 996 GT3
Finally, after Keith Jensen (shared a garage with him) mentioned that he spoke to someone about starting with much lower pressures (perhaps it was you he spoke with) I started at 23/24.
Had to wait a little longer for the pressure to come up BUT I found the tires stayed underneath the car for the remainder of the session. A big improvement. I was able to click off 2:24/ 2:25 lap times much easier than the struggling I was doing earlier to squeak out 26's/27's.
By the end of the session I observed 31/33 f/r.
My plans are to eventually amend my alignment just as I saw you post earlier. I observed a good bit of shoulder wear, not horrible but I know it can be better with a little more neg. camber.
I am hoping that with a little suspension tweaking, better psi management, and more time with the car on circuit, some 2:23's will be acheivable. Perhaps I may have to move to the Trofeo R's for that as well. Time will tell.
Conditions were pretty optimal for lap times - I agree 23s are doable, but it will take similar weather. I am not sure Trofeo Rs are all that much faster than MPSC2s, but availability of the latter was sketchy when I was buying tires, so I decided to give the Trofeos a try.
You were wheeling the car well, so I look forward to any comparison in tires you may make.
12-09-2015, 03:35 PM
#83
Rennlist Member
Ha, yes that was me. I wanted to follow Jensen around as I knew he had more laps there than me. Unfortunately it looked liked his tires were not cooperating as his rear end was all over the place (no rear grip). When I saw you coming, I figured here is an opportunity to learn some lines as I had heard from a little bird earlier that you went low 24's.
So I filed in behind and starting paying attention. Some VERY GOOD driving I might add.
I was wondering what happened to you in 17/18, I saw your car rotate a good bit and noticed I closed in pretty quickly going into 19/20. A nail!!!! What is the world is a nail doing on track????? Just something you wouldn't think you would encounter at COTA.
Sorry to hear about the tire, that sucks. Hopefully no other damage....
Concerning the tire comparison, that is why I was so intent on being on track with both of you. I wanted to see "for myself". If there was discernible difference between the Trofeo R and the MPSC2's. Unfortunately, Jansens tires weren't cooperating and we weren't on track together enough.
Availability is another issue I am not too excited about. I almost had to source a set of Trofeo R's as I couldn't get the MPSC2's. My car originally came with the Dunlops (which are good but do not hold up well to track temps) so I wanted to try the MPSC2's. I guess my next tire to try is the Trofeo R's
Anyway, will have to introduce myself next time, by the way beautiful car (love the yellow) and great driving.
So I filed in behind and starting paying attention. Some VERY GOOD driving I might add.
I was wondering what happened to you in 17/18, I saw your car rotate a good bit and noticed I closed in pretty quickly going into 19/20. A nail!!!! What is the world is a nail doing on track????? Just something you wouldn't think you would encounter at COTA.
Sorry to hear about the tire, that sucks. Hopefully no other damage....
Concerning the tire comparison, that is why I was so intent on being on track with both of you. I wanted to see "for myself". If there was discernible difference between the Trofeo R and the MPSC2's. Unfortunately, Jansens tires weren't cooperating and we weren't on track together enough.
Availability is another issue I am not too excited about. I almost had to source a set of Trofeo R's as I couldn't get the MPSC2's. My car originally came with the Dunlops (which are good but do not hold up well to track temps) so I wanted to try the MPSC2's. I guess my next tire to try is the Trofeo R's
Anyway, will have to introduce myself next time, by the way beautiful car (love the yellow) and great driving.
12-09-2015, 04:31 PM
#84
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Would love to see some COTA video from you guys in your 991 GT3s. I've only been there once, a few months ago, when I borrowed my cousin's 991 GT3. I discovered only at the end that the runoff is part of the track, though I did unintentionally use it a few times. I like the track, but having so many ~40 mph corners seems odd to me.
12-09-2015, 07:25 PM
#85
Would love to see some COTA video from you guys in your 991 GT3s. I've only been there once, a few months ago, when I borrowed my cousin's 991 GT3. I discovered only at the end that the runoff is part of the track, though I did unintentionally use it a few times. I like the track, but having so many ~40 mph corners seems odd to me.
12-10-2015, 12:41 AM
#86
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Not sure how many of you have been to Thermal, but we did some testing there with the RS's and the GMG GT3 and the GT3 with our setup, exhaust and Trofeo R's was just as fast as the RS's, prepped to the same level but the MPSC II's.
Best lap so far on the long course is a 2:13.4.
Best lap so far on the long course is a 2:13.4.
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12-10-2015, 08:26 PM
#87
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I think that was you initially following Jensen and letting me by 3rd session Sunday - I had hoped to continue playing but got a nail in the left rear for some excitement in 16-18, and by the time I was sure it was a tire going down I'd missed pit in and ended up ruining the tire. Glad I trailered.
Conditions were pretty optimal for lap times - I agree 23s are doable, but it will take similar weather. I am not sure Trofeo Rs are all that much faster than MPSC2s, but availability of the latter was sketchy when I was buying tires, so I decided to give the Trofeos a try.
You were wheeling the car well, so I look forward to any comparison in tires you may make.
Conditions were pretty optimal for lap times - I agree 23s are doable, but it will take similar weather. I am not sure Trofeo Rs are all that much faster than MPSC2s, but availability of the latter was sketchy when I was buying tires, so I decided to give the Trofeos a try.
You were wheeling the car well, so I look forward to any comparison in tires you may make.
12-10-2015, 11:04 PM
#88
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When I was at COTA a few months ago, a tire went down on a 991 GT3 with Cup 2. Not sure of the cause, but it seemed to go down within a few laps.
12-17-2015, 01:25 PM
#90
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Seeing that I ran 2:05.4 in my 964 Cup, I hope a 991 GT3 could at least challenge the PCA K class time of 2:04.x, if not run in the 2:01 range.
Heck, I wonder if it should be able to break 2:00. How much does modern technology make up for older tech, 100 fewer hp, lighter weight, and slicks, e.g., I can run sub 2:00 in my 996 Cup, is a current street GT3 not yet on par with a 12 year old Cup car?
I can't speak to many of these track times, but once WGI (and other east coast tracks) is in the discussion, I can contribute.
Heck, I wonder if it should be able to break 2:00. How much does modern technology make up for older tech, 100 fewer hp, lighter weight, and slicks, e.g., I can run sub 2:00 in my 996 Cup, is a current street GT3 not yet on par with a 12 year old Cup car?
I can't speak to many of these track times, but once WGI (and other east coast tracks) is in the discussion, I can contribute.