Tire Pressures
05-17-2006, 01:38 PM
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Last year at Watkins Glen I started a long conversation with Bob Williams at Michelin (864-525-7783). Their feedback from Germany was that all of the track times by the CGT development team were based on cold (morning) psi of 32 even. No deviation. Prior to that I had tried a number of lower pressures, but in the end, went back to 32 psi. My psi monitor at the track, after a 20-30 minute session, routinely shows a rise to 42-43 psi all around, depending on the course. I am on my second set of Pilot Sport Cups after 10+ days of track use. BTW, the car is still better than this driver.
05-18-2006, 06:50 PM
#4
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Track time!
Thanks all for the input: Just came back from the track with the CGT - was able to complete almost 50 laps, while still respecting the break-in rpm (but for those few times my heel and toe was too aggressive ). Cold tire pressures for the MPS2s at 32 pounds. Weather conditions were warm and clear - about 85-95 degrees. Just two cars on the entire 2.2 mile track so had a great opportunity to experiment on the track and on the skid pad.
Initial impressions of CGT: very good - excellent "high speed" stability on the straights and corners, pretty easy to get the car to respond via late/trail braking, pretty easy to catch slides resulting from over rotation (and exaggerated and abrupt steering), fabulous braking from the get go, responsive turn in, smooth power delivery through the "restricted" power band. Car has little body roll, although considerable understeer. I still need work adjusting to the higher shifter location and for whatever reason, my heel and toes weren't crisp or consistent. Considerable tire squeal and greasier performance as track temperatures went up (pretty easy to make the tires squeal, accompanied with understeer). I was able to trigger the ABS a few times under hard braking but didn't trigger the traction control (probably because of the self imposed rev limit) and a pretty judicious right foot.
Overall and FWIW, the CGT is a well balanced, heavy feeling car that appears to be under-tired. While the grip and predictabilility of the MPS2s was good through corners, it felt as though the car was capable of a whole lot more with stickier tires. Some sort of R rated tire would result in much crisper turn in and higher cornerning forces. I can also see how CGT drivers could get in over their heads with the dreaded power throttle oversteer if they were not judicious with their right foot. Despite that, abrupt turns with abrupt throttle off did not result in anything close to the snap oversteer one would normally expect in a GT-2 or other rear engined car. The rear tires stuck very well.
CGT ODO now says 325; can't wait to find redline soon - that should be a trip!!
Initial impressions of CGT: very good - excellent "high speed" stability on the straights and corners, pretty easy to get the car to respond via late/trail braking, pretty easy to catch slides resulting from over rotation (and exaggerated and abrupt steering), fabulous braking from the get go, responsive turn in, smooth power delivery through the "restricted" power band. Car has little body roll, although considerable understeer. I still need work adjusting to the higher shifter location and for whatever reason, my heel and toes weren't crisp or consistent. Considerable tire squeal and greasier performance as track temperatures went up (pretty easy to make the tires squeal, accompanied with understeer). I was able to trigger the ABS a few times under hard braking but didn't trigger the traction control (probably because of the self imposed rev limit) and a pretty judicious right foot.
Overall and FWIW, the CGT is a well balanced, heavy feeling car that appears to be under-tired. While the grip and predictabilility of the MPS2s was good through corners, it felt as though the car was capable of a whole lot more with stickier tires. Some sort of R rated tire would result in much crisper turn in and higher cornerning forces. I can also see how CGT drivers could get in over their heads with the dreaded power throttle oversteer if they were not judicious with their right foot. Despite that, abrupt turns with abrupt throttle off did not result in anything close to the snap oversteer one would normally expect in a GT-2 or other rear engined car. The rear tires stuck very well.
CGT ODO now says 325; can't wait to find redline soon - that should be a trip!!
05-19-2006, 09:18 AM
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Congrats on a fun and safe track experience!
The factory Michelins are quite slippery, and easy on/off throttle
is a must.
Reminder: respect those first 1000 miles for (2) reasons,
1) Porsches says so. 2) You will get to know the car much better WITHOUT
scaring the hell out of yourself or endangering yourself!!
MK
The factory Michelins are quite slippery, and easy on/off throttle
is a must.
Reminder: respect those first 1000 miles for (2) reasons,
1) Porsches says so. 2) You will get to know the car much better WITHOUT
scaring the hell out of yourself or endangering yourself!!
MK
05-19-2006, 10:31 AM
#6
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Thread Starter
Getting to know car
Totally agreed about gaining familiarity with the car!
In all actuality, the rev limit was quite beneficial and educational, as it served two purposes: ramping up my knowledge of the car on the track, and providing an educational backdrop for trying new maneuvers. Having only two cars on the entire track also helped; too often, I don't feel I can experiment much with handling when a lot of other cars are trying to log fast times.
I experimented with trying to maintain a constant speed for the entire course (i.e. no braking) that made for some pretty interesting slides through the corners. Sort of interesting comparison of figuring out the average speed by lap times, and then trying to maintain that average speed everywhere on the course without hard acceleration and hard braking. Interestingly, I was able to stay pretty close to my friend in a turbocharged Lotus Elise and surprisingly, caught him in many of the tighter corners. In addition, I also tried upshifting all the way to 6th that got me to about 80 per cent of the speed I am guessing I would have reached on the straights had I been able to use the full rpms. I also practiced some very abrupt turn ins "at speed" to see how the car would respond - very surprisingly, despite the tires, the rear end had fabulous grip. I also did some extremely late braking runs. Lastly, the whole exercise/experimentation forced me to practice my footwork on oversteer situations; I sometimes have a tendency to apply throttle to try to correct a slide which oftentimes disrupts the balance of car too much and exacerbates the slide. It makes for greater spectator viewing, but certainly not a fast way around a corner.
The laboratory will continued with the rev limit and as long as their is an open track.
In all actuality, the rev limit was quite beneficial and educational, as it served two purposes: ramping up my knowledge of the car on the track, and providing an educational backdrop for trying new maneuvers. Having only two cars on the entire track also helped; too often, I don't feel I can experiment much with handling when a lot of other cars are trying to log fast times.
I experimented with trying to maintain a constant speed for the entire course (i.e. no braking) that made for some pretty interesting slides through the corners. Sort of interesting comparison of figuring out the average speed by lap times, and then trying to maintain that average speed everywhere on the course without hard acceleration and hard braking. Interestingly, I was able to stay pretty close to my friend in a turbocharged Lotus Elise and surprisingly, caught him in many of the tighter corners. In addition, I also tried upshifting all the way to 6th that got me to about 80 per cent of the speed I am guessing I would have reached on the straights had I been able to use the full rpms. I also practiced some very abrupt turn ins "at speed" to see how the car would respond - very surprisingly, despite the tires, the rear end had fabulous grip. I also did some extremely late braking runs. Lastly, the whole exercise/experimentation forced me to practice my footwork on oversteer situations; I sometimes have a tendency to apply throttle to try to correct a slide which oftentimes disrupts the balance of car too much and exacerbates the slide. It makes for greater spectator viewing, but certainly not a fast way around a corner.
The laboratory will continued with the rev limit and as long as their is an open track.
05-19-2006, 06:45 PM
#7
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Thread Starter
CGT v. GT-2 v. GT-3
CGT: A+ for pure driving enjoyment that excites all senses
GT-2: A+ for pure driving excitement that always keeps you on your toes and on edge, and that provides that big pucker factor feeling
GT-3: A+ for pure driving experience on the track - the car just seems to do everything great
Porsche: A+++ for providing great enjoyment, no matter what vehicle!
GT-2: A+ for pure driving excitement that always keeps you on your toes and on edge, and that provides that big pucker factor feeling
GT-3: A+ for pure driving experience on the track - the car just seems to do everything great
Porsche: A+++ for providing great enjoyment, no matter what vehicle!
Trending Topics
05-19-2006, 09:03 PM
#8
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Thread Starter
CGT Observations
"wonder if the pucker factor will increase after break-in on the cgt? 
surprised to hear you say "heavy feeling" referring to the cgt!
also, that you thought the car under-tired even staying below 4200 rpm."
Not sure about the pucker factor; the CGT seems to be an all around better balanced car and much more stable than the GT-2 at higher speeds - you definitely know the weight is behind you in the GT-2; additionally, not having to have to deal with the turbo boost on throttle, especially at the wrong place, should make the CGT more "controllable". Guess time and # of degrees of over-rotation and spins
will tell.
Needed to clarify the heavy feeling comment: I was comparing it to my Challenge Stradale that seems much more responsive and lighter compared to the CGT. The CS doesn't have anywhere the power as the CGT though.
Despite the rpm limit, I managed to get to fourth and even fifth before corners that would have otherwise been third gear entry corners at higher revs. Speed was probably similar or slightly less than at turn in and I am guessing cornering forces were somewhat similar. Front tires had quite a bit of slip and tire squeal, at least more than I would have expected given the corners and the speed. Rears had very good grip. My seat of the pants tire comments come after using the Pirelli Corso system on the Stradale on the track and using MPSCs on the GT-2. In both cases, far greater grip around corners, less tire squeal but only at higher cornering forces, and quicker turn in response.
surprised to hear you say "heavy feeling" referring to the cgt!
also, that you thought the car under-tired even staying below 4200 rpm."
Not sure about the pucker factor; the CGT seems to be an all around better balanced car and much more stable than the GT-2 at higher speeds - you definitely know the weight is behind you in the GT-2; additionally, not having to have to deal with the turbo boost on throttle, especially at the wrong place, should make the CGT more "controllable". Guess time and # of degrees of over-rotation and spins
will tell.Needed to clarify the heavy feeling comment: I was comparing it to my Challenge Stradale that seems much more responsive and lighter compared to the CGT. The CS doesn't have anywhere the power as the CGT though.
Despite the rpm limit, I managed to get to fourth and even fifth before corners that would have otherwise been third gear entry corners at higher revs. Speed was probably similar or slightly less than at turn in and I am guessing cornering forces were somewhat similar. Front tires had quite a bit of slip and tire squeal, at least more than I would have expected given the corners and the speed. Rears had very good grip. My seat of the pants tire comments come after using the Pirelli Corso system on the Stradale on the track and using MPSCs on the GT-2. In both cases, far greater grip around corners, less tire squeal but only at higher cornering forces, and quicker turn in response.
05-23-2006, 02:24 PM
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Originally Posted by thusly
Overall and FWIW, the CGT is a well balanced, heavy feeling car that appears to be under-tired.
Thanks. Your overall impressions are similar to what ex-professional racer, Motoharu "Gan-san" Kurosawa, said during his first drive on the track in the Best Motoring video:
Car&Driver and MotorTrend have stated the Stradale and CGT curb weights as 3157 and 3258 lbs. respectively. Do you feel the approx. 100 lb. weight difference on the track and on the street? Are you actually feeling the weight difference or more the design differences or a little of both? Also, between the Cup, Stradale, and CGT, which one feels the most stable at higher speeds?
Originally Posted by thusly
Despite that, abrupt turns with abrupt throttle off did not result in anything close to the snap oversteer one would normally expect in a GT-2 or other rear engined car. The rear tires stuck very well.
Links:
http://store.driftingshop.com/enchbybemoin.html
http://www.motortrend.com/roadtests/...rformance.html
https://rennlist.com/forums/996-gt2-gt3-forum/101663-car-and-driver-jan04-gt3-vs-stradale-vs-ford-gt.html
05-23-2006, 04:38 PM
#10
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Thread Starter
CGT vs. CS vs. GT-2
Haven't seen the Best Motoring video on the CGT - I will need to check it out!
From a seat of the pants perspective only, the Stradale just seems livelier with quicker/more responsive steering than the CGT. Not to say the CGT is heavy; just heavier as compared to the CS. To me, there is a certain "lightness" in steering exhibited by my CS and 550 - a Ferrari thing?? Not sure it is attributed to weight; the CGT feels very solid and planted. Not being anything close to an engineer, I would imagine that the differences are due to design/chassis, as well as very good aerodynamics (as compared to the GT-2). As far as high speed stability, the CGT feels the best (I haven't been able to get over 120 so far, but would envision that the aerodynamics would make the car even better at faster speeds). CS is very good as well, but would seem to be more "twitchier" than the CGT at speeds about 125mph. The GT-2s is much twitchier at high speeds altogther, and much more so than the CS. Motons helped quite a bit, but nevertheless, both the CS and CGT feel much more planted.
Lastly, very safe to assume I didn't do throttle lifts at 130mphs - my car control skills clearly aren't anywhere at that level!
From a seat of the pants perspective only, the Stradale just seems livelier with quicker/more responsive steering than the CGT. Not to say the CGT is heavy; just heavier as compared to the CS. To me, there is a certain "lightness" in steering exhibited by my CS and 550 - a Ferrari thing?? Not sure it is attributed to weight; the CGT feels very solid and planted. Not being anything close to an engineer, I would imagine that the differences are due to design/chassis, as well as very good aerodynamics (as compared to the GT-2). As far as high speed stability, the CGT feels the best (I haven't been able to get over 120 so far, but would envision that the aerodynamics would make the car even better at faster speeds). CS is very good as well, but would seem to be more "twitchier" than the CGT at speeds about 125mph. The GT-2s is much twitchier at high speeds altogther, and much more so than the CS. Motons helped quite a bit, but nevertheless, both the CS and CGT feel much more planted.
Lastly, very safe to assume I didn't do throttle lifts at 130mphs - my car control skills clearly aren't anywhere at that level!
05-24-2006, 10:43 AM
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Originally Posted by thusly
To me, there is a certain "lightness" in steering exhibited by my CS and 550 - a Ferrari thing??
Originally Posted by thusly
CS is very good as well, but would seem to be more "twitchier" than the CGT at speeds about 125mph. The GT-2s is much twitchier at high speeds altogther, and much more so than the CS. Motons helped quite a bit, but nevertheless, both the CS and CGT feel much more planted.
Is it safe to assume the GT-2 alignment was checked with OEM shocks as well as the Motons and still was much twitchier than the CS?
05-24-2006, 03:01 PM
#12
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Thread Starter
GT-2 v GT-3
Based on my experiences, alignment and suspension set up are extremely important with the GT-2 and GT-3. Before Motons, the GT-2 was borderline scary - really had a fine edge to it: totally losing it to feeling somewhat ok about it. At that time, the GT-2's alignment and settings were checked with factory specs. My first GT-3 also felt skittish, but the alignment settings were way off. In both cases, and after Motons and corner balancing, both cars respond very well, ride better, handle better and in the case of the GT-2, is far more "tame". The Motons made the largest difference in the GT-2s handling. Can't really say how the GT-2 and GT-3 compare at 125mph and above as far as twitchiness, as I haven't done back to backs on the road. Suffice to say, I do feel comfortable in both when driven at those speeds (very short periods on the track as opposed to on the road). I have found myself driving the GT-2 with the same spirit as the GT-3 on the track; before Motons, I never thought I would even get to that "comfortable feeling" and the suspension mods really were the key reason.
Even with the Moton set-up on the GT-2, I still think that the CS feels like it has more stability than the GT-2 (at least on the road), although that gap has narrowed considerably.
Even with the Moton set-up on the GT-2, I still think that the CS feels like it has more stability than the GT-2 (at least on the road), although that gap has narrowed considerably.
05-24-2006, 03:32 PM
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Originally Posted by thusly
Can't really say how the GT-2 and GT-3 compare at 125mph and above as far as twitchiness, as I haven't done back to backs on the road. Suffice to say, I do feel comfortable in both when driven at those speeds (very short periods on the track as opposed to on the road). I have found myself driving the GT-2 with the same spirit as the GT-3 on the track; before Motons, I never thought I would even get to that "comfortable feeling" and the suspension mods really were the key reason.
