Impressions of GT3 (Manifold)
09-26-2015, 03:57 PM
#227
I am far from the experience level of Manifold and others on this forum as I have only 2,000 miles of track experience and all of that in my GT3. However, I have had some excellent coaching for most of those miles and my coach emphasizes smoothness on both the throttle and the brake, on and off on both -- maybe it's the PASM or something else, but he feels that the car is more easily upset by abrupt inputs than you would expect from such a capable car.
All cars regardless of capability are susceptible to input. The better the car the more susceptible. Any input that alters trajectory has a shift in weight which is where the shift is. While it can happen quickly, all on or off will mean a rebound of some kind and thus a certain amount of unsealing of the car. Better divers will be able to ramp up control pressure so as weight shifts remains shifted without rebound. This is the biggest challenge to becoming a better more accomplished driver and will be repaid in spades as time ability progresses.
09-26-2015, 08:25 PM
#228
All cars regardless of capability are susceptible to input. The better the car the more susceptible. Any input that alters trajectory has a shift in weight which is where the shift is. While it can happen quickly, all on or off will mean a rebound of some kind and thus a certain amount of unsealing of the car. Better divers will be able to ramp up control pressure so as weight shifts remains shifted without rebound. This is the biggest challenge to becoming a better more accomplished driver and will be repaid in spades as time ability progresses.
10-27-2015, 12:01 PM
#229
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Just got back from a Chin event at VIR where there were multiple 991 GT3s.
In addition to driving my car with factory alignment and Sport Cup 2, I also drove another one, and rode in one with fellow RLer rm21.
Both of the other two had the Crawford wing and some alignment changes, and rm21 was on Trofeo R.
The one I drove did seem to have a slightly more pinned down rear under hard braking from 150+ mph, due to the wing, without causing understeer (not sure what was done with the front of the car). Didn't like the brake pedal feel, too much travel and softness, less feel than my brakes (Ferodo pads, AP Racing front rotor, SRF). I suspect that the fluid was boiled, but the Pagid (Yellow?) pads might also be a factor. Otherwise, the car felt very similar to mine, and I like the tight Recaro race seat over my LWB. (Have also driven my cousin's 991 GT3, which has the same setup as my car, and it felt identical to mine).
From the right seat, rm21's car also seemed to benefit from the big wing, and, combined with the tires, was dialed in such that it gave me the impression of better handling and more grip than my car. rm21 is miles ahead of me in terms of researching how to improve the car, and I'm becoming convinced that the car can/should be tweaked to make it better for the track, though that requires some real expertise in order to make it better rather than worse. I plan to take my car to TPC Racing to get their proprietary alignment tweak, as well as their side muffler bypass - I was envious of the sound of rm21s car! Will stick with SC2 for now, but riding in some cars on slicks made me wonder ...
rm21 was driving really well. His first time at VIR, learned the track quickly, and by day 2 he blew the doors off a couple other 991 GT3s in the intermediate group and moved to the top group. He needs to instruct!
In addition to driving my car with factory alignment and Sport Cup 2, I also drove another one, and rode in one with fellow RLer rm21.
Both of the other two had the Crawford wing and some alignment changes, and rm21 was on Trofeo R.
The one I drove did seem to have a slightly more pinned down rear under hard braking from 150+ mph, due to the wing, without causing understeer (not sure what was done with the front of the car). Didn't like the brake pedal feel, too much travel and softness, less feel than my brakes (Ferodo pads, AP Racing front rotor, SRF). I suspect that the fluid was boiled, but the Pagid (Yellow?) pads might also be a factor. Otherwise, the car felt very similar to mine, and I like the tight Recaro race seat over my LWB. (Have also driven my cousin's 991 GT3, which has the same setup as my car, and it felt identical to mine).
From the right seat, rm21's car also seemed to benefit from the big wing, and, combined with the tires, was dialed in such that it gave me the impression of better handling and more grip than my car. rm21 is miles ahead of me in terms of researching how to improve the car, and I'm becoming convinced that the car can/should be tweaked to make it better for the track, though that requires some real expertise in order to make it better rather than worse. I plan to take my car to TPC Racing to get their proprietary alignment tweak, as well as their side muffler bypass - I was envious of the sound of rm21s car! Will stick with SC2 for now, but riding in some cars on slicks made me wonder ...
rm21 was driving really well. His first time at VIR, learned the track quickly, and by day 2 he blew the doors off a couple other 991 GT3s in the intermediate group and moved to the top group. He needs to instruct!
Last edited by Manifold; 10-27-2015 at 01:43 PM.
10-27-2015, 07:51 PM
#230
Burning Brakes
Just got back from a Chin event at VIR where there were multiple 991 GT3s.
In addition to driving my car with factory alignment and Sport Cup 2, I also drove another one, and rode in one with fellow RLer rm21.
Both of the other two had the Crawford wing and some alignment changes, and rm21 was on Trofeo R.
The one I drove did seem to have a slightly more pinned down rear under hard braking from 150+ mph, due to the wing, without causing understeer (not sure what was done with the front of the car). Didn't like the brake pedal feel, too much travel and softness, less feel than my brakes (Ferodo pads, AP Racing front rotor, SRF). I suspect that the fluid was boiled, but the Pagid (Yellow?) pads might also be a factor. Otherwise, the car felt very similar to mine, and I like the tight Recaro race seat over my LWB. (Have also driven my cousin's 991 GT3, which has the same setup as my car, and it felt identical to mine).
From the right seat, rm21's car also seemed to benefit from the big wing, and, combined with the tires, was dialed in such that it gave me the impression of better handling and more grip than my car. rm21 is miles ahead of me in terms of researching how to improve the car, and I'm becoming convinced that the car can/should be tweaked to make it better for the track, though that requires some real expertise in order to make it better rather than worse. I plan to take my car to TPC Racing to get their proprietary alignment tweak, as well as their side muffler bypass - I was envious of the sound of rm21s car! Will stick with SC2 for now, but riding in some cars on slicks made me wonder ...
rm21 was driving really well. His first time at VIR, learned the track quickly, and by day 2 he blew the doors off a couple other 991 GT3s in the intermediate group and moved to the top group. He needs to instruct!
In addition to driving my car with factory alignment and Sport Cup 2, I also drove another one, and rode in one with fellow RLer rm21.
Both of the other two had the Crawford wing and some alignment changes, and rm21 was on Trofeo R.
The one I drove did seem to have a slightly more pinned down rear under hard braking from 150+ mph, due to the wing, without causing understeer (not sure what was done with the front of the car). Didn't like the brake pedal feel, too much travel and softness, less feel than my brakes (Ferodo pads, AP Racing front rotor, SRF). I suspect that the fluid was boiled, but the Pagid (Yellow?) pads might also be a factor. Otherwise, the car felt very similar to mine, and I like the tight Recaro race seat over my LWB. (Have also driven my cousin's 991 GT3, which has the same setup as my car, and it felt identical to mine).
From the right seat, rm21's car also seemed to benefit from the big wing, and, combined with the tires, was dialed in such that it gave me the impression of better handling and more grip than my car. rm21 is miles ahead of me in terms of researching how to improve the car, and I'm becoming convinced that the car can/should be tweaked to make it better for the track, though that requires some real expertise in order to make it better rather than worse. I plan to take my car to TPC Racing to get their proprietary alignment tweak, as well as their side muffler bypass - I was envious of the sound of rm21s car! Will stick with SC2 for now, but riding in some cars on slicks made me wonder ...
rm21 was driving really well. His first time at VIR, learned the track quickly, and by day 2 he blew the doors off a couple other 991 GT3s in the intermediate group and moved to the top group. He needs to instruct!
10-27-2015, 07:57 PM
#231
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10-28-2015, 07:14 AM
#232
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Just got back from a Chin event at VIR where there were multiple 991 GT3s.
In addition to driving my car with factory alignment and Sport Cup 2, I also drove another one, and rode in one with fellow RLer rm21.
Both of the other two had the Crawford wing and some alignment changes, and rm21 was on Trofeo R.
The one I drove did seem to have a slightly more pinned down rear under hard braking from 150+ mph, due to the wing, without causing understeer (not sure what was done with the front of the car). Didn't like the brake pedal feel, too much travel and softness, less feel than my brakes (Ferodo pads, AP Racing front rotor, SRF). I suspect that the fluid was boiled, but the Pagid (Yellow?) pads might also be a factor. Otherwise, the car felt very similar to mine, and I like the tight Recaro race seat over my LWB. (Have also driven my cousin's 991 GT3, which has the same setup as my car, and it felt identical to mine).
From the right seat, rm21's car also seemed to benefit from the big wing, and, combined with the tires, was dialed in such that it gave me the impression of better handling and more grip than my car. rm21 is miles ahead of me in terms of researching how to improve the car, and I'm becoming convinced that the car can/should be tweaked to make it better for the track, though that requires some real expertise in order to make it better rather than worse. I plan to take my car to TPC Racing to get their proprietary alignment tweak, as well as their side muffler bypass - I was envious of the sound of rm21s car! Will stick with SC2 for now, but riding in some cars on slicks made me wonder ...
rm21 was driving really well. His first time at VIR, learned the track quickly, and by day 2 he blew the doors off a couple other 991 GT3s in the intermediate group and moved to the top group. He needs to instruct!
In addition to driving my car with factory alignment and Sport Cup 2, I also drove another one, and rode in one with fellow RLer rm21.
Both of the other two had the Crawford wing and some alignment changes, and rm21 was on Trofeo R.
The one I drove did seem to have a slightly more pinned down rear under hard braking from 150+ mph, due to the wing, without causing understeer (not sure what was done with the front of the car). Didn't like the brake pedal feel, too much travel and softness, less feel than my brakes (Ferodo pads, AP Racing front rotor, SRF). I suspect that the fluid was boiled, but the Pagid (Yellow?) pads might also be a factor. Otherwise, the car felt very similar to mine, and I like the tight Recaro race seat over my LWB. (Have also driven my cousin's 991 GT3, which has the same setup as my car, and it felt identical to mine).
From the right seat, rm21's car also seemed to benefit from the big wing, and, combined with the tires, was dialed in such that it gave me the impression of better handling and more grip than my car. rm21 is miles ahead of me in terms of researching how to improve the car, and I'm becoming convinced that the car can/should be tweaked to make it better for the track, though that requires some real expertise in order to make it better rather than worse. I plan to take my car to TPC Racing to get their proprietary alignment tweak, as well as their side muffler bypass - I was envious of the sound of rm21s car! Will stick with SC2 for now, but riding in some cars on slicks made me wonder ...
rm21 was driving really well. His first time at VIR, learned the track quickly, and by day 2 he blew the doors off a couple other 991 GT3s in the intermediate group and moved to the top group. He needs to instruct!
Last edited by rm21; 10-28-2015 at 07:33 AM.
10-28-2015, 08:14 AM
#234
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rm21. What alignment setting are you using? Im not sure how they translate for those of us on MPSC2 without the additional aero but keen to learn how you have the suspension set up. having the Cup splitter will help in balancing out the downforce over the front axle I guess. Nice work.
10-28-2015, 09:55 AM
#235
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rm21. What alignment setting are you using? Im not sure how they translate for those of us on MPSC2 without the additional aero but keen to learn how you have the suspension set up. having the Cup splitter will help in balancing out the downforce over the front axle I guess. Nice work.
I can say that I am following what seems to be the consensus on the Trofeo pressures - 29 front and 31 rear seem optimal for my driving. I also just did a Ross Bentley webinar on suspension tuning and learned a nice trick. If you put an air-dryer (basically a desiccant cylinder) inline from your air compressor, you can get the humidity out of your air and it is far easier to regulate pressures. He suggested it is a bit better than using nitrogen. It is a pain, since you need to deflate and inflate your tires 2-3 times, but since I generally don't trailer my car and have access to a big tank of nitrogen, it is a nice poor man's solution.
At this point, I've got a ton of driver improvement left so I'm done with suspension tuning. I'm running consistent 1:34s at Road Atlanta, but my latest split time composites were 1:31.5, so I'm still very inconsistent. I realize you can't take composite times at face value since you can always overcook a braking zone but then kill your entry to the next turn, but 1:31s are close to pro territory so it is a motivating metric!
Would love to find some other folks with Solo DLs on RL to share data feeds. I know you're a bit far away for that! RL has been great for helping me get the car to this point.
10-28-2015, 10:21 AM
#236
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Manifold - Thanks for the kind words. You are an awesome driver and instructor - you made it easy for me to learn the line and advance to red. It was nice to have an expert driver validate the fact that I think my car is finally dialed in. It took a few iterations to get the right setup with the giant wing and cup splitter! When I turned the car into my race shop they also couldn't believe how well the tires were wearing after six track days. I wish you could have felt the car when the tires were new - the grip was even better. I'm starting to become a real believer in the Trofeos, at least for the tracks I drive. I'm going to see if I can squeak out another two days at Barber in several weeks. Hope to see you again soon at VIR, or maybe Road Atlanta.
).I don't know how the rubber compounds compare between the Trofeo R and the Sport Cup 2, but the TR seems to have an advantage in apparently using the same rubber across the tread and having less grooves in the tread, though of course that makes the SC2 better and safer in the rain, which is a factor for a car which isn't being trailered. I think my next iteration will be to try the TPC alignment with the SC2, but I'm open to considering the TR in the future. Maybe the TR is the closest approximation to a slick we can get without voiding the warranty. And if the alignment and tire pressures are dialed in, being able to make use of good rubber across the whole tread can help with tire wear and durability.
But you make a good point about the behavior of the car and tires being track dependent. My car likes my home track, Summit Point Main, the least among the several tracks I've been to, and I think the bumpiness at high speeds, especially in braking zones, is a big factor in that. I've wondered if the PASM just can't cope with that. Having done a lot of days with the car at SP, I've adapted by modulating the brakes better, but I've now had two super-experienced CIs drive my car at SP and, near the limit, both found it to be a handful to a surprising extent (whereas you saw that the car was pretty good at VIR). So that further convinces me that it's worth trying the TPC alignment tweak (which I understand to be intended for use with the SC2).
I really like Chin, and will be a doing a bunch of events with them next year, including probably two or three at VIR. Let's definitely plan to run and ride together again. Once you get more seat time at VIR, I may not be able to keep up with you!
LOL on how I got mixed up on the checkouts. How many people could there be who are driving a GT3, initials of RM, in Red at other tracks with Chin, first time at VIR so starting in Blue, and would like to do some sessions at the track before a Red checkout. Well, apparently there were at least two at this event!
10-28-2015, 01:21 PM
#237
Drifting
10-28-2015, 01:29 PM
#238
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It's not a famous track, and the facilities are just ok, but it's a quality lap with a good variety of geometrics and good flow, and I'm still not bored with the track after having done many dozens of days there. The other two tracks at Summit Point (Shenandoah and Jefferson) are also worth checking out.
10-28-2015, 01:38 PM
#239
Drifting
Since my son and I are both tracking, we decided to buy a 2nd track car and went with a SB. He is away at college so I'm tracking solo. The SB is a ton of fun so I've been using that instead of the GT3. When he tracks with me I will use the GT3 and he will use the SB.
10-28-2015, 01:44 PM
#240
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Manifold - Thanks for the kind words. You are an awesome driver and instructor - you made it easy for me to learn the line and advance to red. It was nice to have an expert driver validate the fact that I think my car is finally dialed in. It took a few iterations to get the right setup with the giant wing and cup splitter! When I turned the car into my race shop they also couldn't believe how well the tires were wearing after six track days. I wish you could have felt the car when the tires were new - the grip was even better. I'm starting to become a real believer in the Trofeos, at least for the tracks I drive. I'm going to see if I can squeak out another two days at Barber in several weeks. Hope to see you again soon at VIR, or maybe Road Atlanta.