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View Full Version : Track Attack #11, New tires, best lap time, max g’s, 991 Turbo S…and the big question



Bruce H.
10-16-2014, 11:09 PM
Sept 3, 2014 – '14 Viper TA at Canadian Tire Motorsports Park (Mosport)

My last track event was here just two days ago, and the last on the original front Corsa tires. They had worn very well over 10 track days and 14,000 kms (~8000 miles). Today I was on new fronts that were just installed, and the original half worn rears. I had expected that the new tires would be a bit slippery until the tire’s release agents burned off, or a bit squirmy due to full tread and no heat cycles. That wasn’t the case, and was able to run them at my usual pace, logging in excess of 1.50 g’s in corners, and 1.48 g under braking, which is just shy of the 1.5g braking grip on the old fronts in their final laps. So these tires are terrific when brand new, half worn, and actually at their absolute best even as they are cording… and recording their fastest laps!

Previous day's peak g's prior to resetting for today
http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/TA%20Datalogs/IMG-20140903-00139_zps7db285e8.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/TA%20Datalogs/IMG-20140903-00139_zps7db285e8.jpg.html)
Lining up in the hot pits
http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/DSC_7768_zpsed267b85.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/DSC_7768_zpsed267b85.jpg.html)

Last day a track buddy and I started to use data-logging as a tool to compare various laps in my car against those in his race car in an effort to identify possible areas for improvement. This is the day that Kuno Wittmer was going to be doing some personal coaching with me and he wanted to use data-logging as well, comparing laps he would run in my car to laps that I would then do. Unfortunately the expected delivery date of his son was moved ahead, and a little too close for comfort for him to be several hours away at the track. Kuno’s day will be rescheduled.

Pretty decent resting stance with just 3 1/2" clearance under front splitter, and surely less with me it!
http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/DSC_77592_zps15f190b0.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/DSC_77592_zps15f190b0.jpg.html)
...and under throttle on the front straight
http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/DSC_7853_zps6f75d3e8.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/DSC_7853_zps6f75d3e8.jpg.html)

The data-logging and pointers from my track friend had lowered my lap time to a personal best 1:35:41 two days ago, and as I became more practiced with those slight driving changes today I was able to further reduce that to a new best 1:34:67. This is a phenomenal lap time at Mosport for a bone stock production car by any high-end performance brand, and while I’m not pushing the car, I continue to drive within my comfort zone. I’ve been conservative in that regard all season as I’ve watched lap times consistently fall from having the extra seat time, rather than pushing beyond my comfort zone. I’m sure there’s another few seconds to peel away with better driving, and that will happen as I find improved techniques, competence and confidence with more seat time. The challenge and reward is in improving my driving as measured by lap times, and there’s no short cut to getting there other than seat time, training and on-going analysis.

http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/DSC_7894_zps2adbf937.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/DSC_7894_zps2adbf937.jpg.html)

http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/DSC_8165_zps6e91ee82.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/DSC_8165_zps6e91ee82.jpg.html)

It became obvious that the car’s on-board G meter can only record up to 1.5 g under cornering since it reads that “peak” after most days on this track. I find the G display useful in that it generally indicates or confirms how confident I am on any given track, with 1.5g indicating I'm on it. Since a peak number doesn’t really tell you very how you're doing all around the track I checked the QRacing data-logger which records and displays g forces continuously around the track, showing them above 1.5 regularly in level (non-banked) corners on this track which I've run over many years. The Corsa tires really do get sticky when heated to track temps, and they really do maintain incredible grip lap after lap. SRT made an excellent choice for a fully streetable tire…but there’s no doubt in my mind that the Michelin Pilot Sport Cup 2 tire offers superior grip on track, and would be an even better streetable choice, at least in the warmer weather.

Here’s a short video that captures some of the action, including passing a few very nice cars. I'm using a lot less brake now than I used to, and trying different lines. At the end of the long back straight I'm trying that corner as a double apex, entering on the inside to brake later and deeper which the car seems to like. In this clip is the new 2014 911 (991) Turbo Sport that did run an even quicker lap time of 1:32:2 using lighter after-market wheels and a tire change to the MPSC2’s, which were a huge improvement he claimed. He’s highly trained and skilled, and I’d suggest the quickest of these two cars would be whichever one he was driving! He has the new 2015 GT3 RS on order, and I have a feeling I’m going to need a LOT more seat time and better tires if I hope to keep up to him in that! And you'll hear why you should always disconnect your cell phone's blue tooth when heading out on the track ;) Enjoy!


https://www.youtube.com/watch?v=yos9iTxyhhs

What seemed different today was the frequency that I had the rear stepping out. The first few times it happens you wonder how far out it will go, will you catch it, will the car spin, etc…and then why did it come out. Since I’ve taken the time to work my speeds up slowly when the rear has come out it has been pretty gentle and easily catchable with a little opposite steering input and usually staying on the throttle…and in some cases doing nothing and it tucks back in. So today again it was a non-event each time, and I could mostly anticipate it rather than simply react to it. Data logging showed how just a couple of mph greater entry speed into a corner was enough to loosen the rear at mid corner. That doesn’t necessarily mean that was as fast as the car could go, but rather perhaps the fastest it could go with the amount of throttle I was using, and the weight that I was keeping transferred onto the rear tires at the time. In most cases I had induced the slide with throttle-on over-steer exiting a corner, in another it was while dropping 100 feet down the infamous T2 without enough throttle to keep the weight shifted rearward to maintain rear grip. That’s a corner that requires a solid commitment, and an extra 2-3 mph entry speed was enough to remind me of that. The lesson isn’t to enter slower, but rather keep your foot in it enough to keep the car balanced.

http://i49.photobucket.com/albums/f262/GT2860RS/Viper%20TA/DSC_8459_zpse7a2d6c1.jpg (http://s49.photobucket.com/user/GT2860RS/media/Viper%20TA/DSC_8459_zpse7a2d6c1.jpg.html)

I primarily do 6th Gear lapping days when at Mosport. They only accept advanced level drivers so there is no need for run groups. You simply drive for as long as you like, or until your tank is empty. Great bunch of guys driving the best of the best. Every day looks like a Lightning Lap comparo about to happen, although probably half are gutted out race cars, and many others are trailered and running slicks. Usually one very well driven ACR-X there to remind us all of which car can ape-rape whatever you might bring, and sometimes a local Comp Coupe racer in his stock '08 ACR. This would be the stock and road legal car that was running quicker times this day.

http://i49.photobucket.com/albums/f262/GT2860RS/Other%20cars%20at%20track%20events/IMG-20140903-00132_zpsab893b32.jpg (http://s49.photobucket.com/user/GT2860RS/media/Other%20cars%20at%20track%20events/IMG-20140903-00132_zpsab893b32.jpg.html)

http://i49.photobucket.com/albums/f262/GT2860RS/Other%20cars%20at%20track%20events/IMG-20140903-00133_zps7d1f23d5.jpg (http://s49.photobucket.com/user/GT2860RS/media/Other%20cars%20at%20track%20events/IMG-20140903-00133_zps7d1f23d5.jpg.html)

http://i49.photobucket.com/albums/f262/GT2860RS/Other%20cars%20at%20track%20events/IMG-20140903-00134_zps9a794c9e.jpg (http://s49.photobucket.com/user/GT2860RS/media/Other%20cars%20at%20track%20events/IMG-20140903-00134_zps9a794c9e.jpg.html)

http://i49.photobucket.com/albums/f262/GT2860RS/Other%20cars%20at%20track%20events/IMG-20140903-00137_zps05c17b61.jpg (http://s49.photobucket.com/user/GT2860RS/media/Other%20cars%20at%20track%20events/IMG-20140903-00137_zps05c17b61.jpg.html)

http://i49.photobucket.com/albums/f262/GT2860RS/Other%20cars%20at%20track%20events/IMG-20140903-00136_zps2638d140.jpg (http://s49.photobucket.com/user/GT2860RS/media/Other%20cars%20at%20track%20events/IMG-20140903-00136_zps2638d140.jpg.html)

Now for the big question: Is the TA better on track than the SRT or GTS with Track Pack?

Answer: How would I know….I’m still so far from reaching this car’s limits that I‘m sure I wouldn’t have reached their limits either :) The one who would really know is the driver who is comfortable somewhat gently sliding the car around every corner, balancing it on the limits of adhesion from corner entry to exit. A 10% tire slip angle is supposedly when the tire achieves its greatest grip, so unless you are holding it on the edge of sliding it you’re just not there yet. That's what a pro driver like Randy Pobst can do when testing cars, and what many racers do in their own for their fastest lap times. And I suspect it’s mostly when driving at those lofty limits that any differences would become very obvious. So unless you’re that driver, I would suggest that most of us could take any Gen V on the track and run similar times, and have just as much fun while improving our driving skill behind the wheel of one very impressive exotic!

And for this we can thank Ralph Gilles, and the entire Viper team of enthusiasts who make Track Rat’s dreams come true!

Bruce

CC39
10-17-2014, 07:35 AM
Awesome video! As a new owner, this inspires me. Thanks for sharing.

Bruce H.
10-17-2014, 08:20 AM
That's fantastic! Welcome, and are you considering tracking yours?


Awesome video! As a new owner, this inspires me. Thanks for sharing.

The_Greg
10-17-2014, 08:47 AM
Those pictures make me re-consider my favorite TA color.... I thought I liked Orange best but man, yours looks fantastic on the track!

mjorgensen
10-17-2014, 08:57 AM
Great post Bruce, that should get some more GenV and others more interested in tracking their Vipers!

Bruce H.
10-17-2014, 09:16 AM
Those pictures make me re-consider my favorite TA color.... I thought I liked Orange best but man, yours looks fantastic on the track!
Thanks..hard to choose as they're all great!


Great post Bruce, that should get some more GenV and others more interested in tracking their Vipers!
Thanks, and that's the plan :)

J TNT
10-17-2014, 10:28 AM
Thanks Bruce for another engaging great post ! Very informative for those at all levels . You must have been a journalist in your past life and would make Denis Jenkinson Proud ! ;)
I've been keeping my eye on the MPSC2 for the last 6 months and hope to try them this spring :)
Look forward to seeing you and your wife at the year end party . :very_drunk:

AZMotorgod
10-17-2014, 11:34 AM
Bruce,

Your TA is unbelievably gorgeous.

If that was a call coming in on your Bluetooth, that would have been awesome if a buddy would have been calling and you answered it and he said, "What's up?" And your reply (Like a Boss), "nothing, just almost hitting 150 on the straight, and you?"

rw99
10-17-2014, 01:41 PM
Thanks for posting, Bruce. Mosport looks like a really fun track, and it seemed like you were running with a good group of drivers.

I'm envious of your opportunity to get some coaching from Kuno, especially with matched telemetry! Invaluable info, truly. Hope it happens.

aaron94t
10-17-2014, 02:19 PM
Great post, thanks for taking the time. It is amazing that you can be passing full race cars while getting a car initiated Bluetooth call! It really shows how amazingly capable the car is. Keep up the good work, nice smooth driving throughout.

FLATOUT
10-17-2014, 02:35 PM
I love it Bruce! You get out way more often than I have been able to lately wich truly makes me sad lol. To me there is nothing better than having the car out running laps.

slowhatch
10-17-2014, 03:25 PM
Bruce love reading your updates/threads! Makes me just want to climb in the car and head to the nearest track!

Bruce H.
10-17-2014, 11:23 PM
Thanks guys for all the great compliments! I'm just glad that many find these "Track Attack" threads interesting, and I'm glad you've been enjoying the ride from showroom thru Season 1. The next report will be from the TA's first day at Calabogie Motorsports Park in north-eastern Ontario, followed by a return visit to the very scenic Le Circuit Mont Tremblant in Quebec (Randy Pobst's favorite track in North America), and then it's Back in Black to Mosport for the season-ending Track Attack #14 of 2014!


Thanks Bruce for another engaging great post ! Very informative for those at all levels . You must have been a journalist in your past life and would make Denis Jenkinson Proud ! ;)
I've been keeping my eye on the MPSC2 for the last 6 months and hope to try them this spring :)
Look forward to seeing you and your wife at the year end party . :very_drunk:

Thanks Jay. You might be right about that, and I think many of us also share the passion for high performance driving with Denis. Those tires would be a great replacement for those old hockey pucks you were telling me about, and a good choice to spend some quality seat time with at the track in 2015! Looking forward to seeing you both and the rest of the gang at the party also!

SilveRT8
10-18-2014, 08:27 AM
Thanks guys for all the great compliments! I'm just glad that many find these "Track Attack" threads interesting, and I'm glad you've been enjoying the ride from showroom thru Season 1. The next report will be from the TA's first day at Calabogie Motorsports Park in north-eastern Ontario, followed by a return visit to the very scenic Le Circuit Mont Tremblant in Quebec (Randy Pobst's favorite track in North America), and then it's Back in Black to Mosport for the season-ending Track Attack #14 of 2014! !

Hi Bruce,
When is Tremblant and who is organising it ? I'm 1:30 h away

Bruce H.
10-18-2014, 09:08 AM
Hey Claude,
It was a private day on Sept 24th...I just need to write it up. Have you driven LCMT before?


Hi Bruce,
When is Tremblant and who is organising it ? I'm 1:30 h away

SilveRT8
10-18-2014, 10:05 AM
Hey Claude,
It was a private day on Sept 24th...I just need to write it up. Have you driven LCMT before?

Yes, we rent Tremblant twice a year through the VOA Quebec with our Prez Andras K, also 3 Lapping days at Circuit Icar and once a year for Calabogie
All those are open, so you would be welcome to join us next summer

Shooter
10-18-2014, 08:55 PM
Good write up. Enjoyed reading it. Keep em coming.

Nine Ball
10-19-2014, 06:39 AM
Enjoyed the read. Thanks!

Tony

1ststrike
10-19-2014, 10:49 AM
Really enjoyed your video. Who's camera are you using? Keep those Track Attacks coming. Your car looks killer on the track.

Bruce H.
10-19-2014, 05:03 PM
Thanks guys!


Yes, we rent Tremblant twice a year through the VOA Quebec with our Prez Andras K, also 3 Lapping days at Circuit Icar and once a year for Calabogie
All those are open, so you would be welcome to join us next summer

I would be interested in joining you guys but didn't find any info/contacts on your Quebec forum. Please provide if you don't mind.


Really enjoyed your video. Who's camera are you using? Keep those Track Attacks coming. Your car looks killer on the track.

Ojocam Mini801 with GPS and 32 mb card. I have one mounted on windshield with optional hard-wire kit to the car's supplied rear view mirror cord which you car barely see in the video to the right of mirror, and a second one between the seats with power cord I plug into the rear console jack that when heading out on the track. That way I always have automatic and loop monitoring to catch anything that might happen on the street, and separate recording of only track sessions. The 1080p resolution is great, but I use 720p to upload onto youtube. http://www.ojocam.com/

1ststrike
10-19-2014, 07:52 PM
THanks for the camera info! Looks like a fun track!

VENOM V
10-20-2014, 06:08 PM
Very cool Bruce, congrats on the new personal best! I’m just back in town from Buttonwillow Raceway, catching up on your adventures.
Were the new fronts shaved, or full tread depth? First time I tracked on my Corsas, I got the “groove of doom,” where the tread block row 2nd from the outside had worn away. In the proceeding track days, the wear evened out so not sure if it’s a biggie. If/when I replace mine, I may go shaved.

Good that you’ll still get a chance to track with Kuno. At my favorite track Buttonwillow I thought I knew the line until I was coached by Jonathan “Redsled” Martinez, who drives a Gen II GTS-R. He’s the man at Buttonwillow; he’s logged thousands of miles there and gave me tips on every nook, cranny, bump and curbing. My times dropped literally by seconds after his insightful coaching, I’m a true believer.

Damn that video looks fun. Nothing like dicing through a bunch of guys on your way to the front. And I suspect that the 991 Turbo’s MPSC2s account for the difference in your lap times. You ought to both throw Hoosiers on and have at it boys! I know, you just bought your new Corsas, but I swear that Hoosiers were made for the Viper. I ran 315s front, 345s rear, and the extra grip in the front elimates that last bit of understeer at the limit.

Regarding the rear stepping out, you are wheeling that bad machine. I’m curious if you’re tracking with stability control on? Last weekend I turned it completely off for the first time, and picked up measurable time per lap. I found that I’m able to controllably toss the car around a little more, and that it’s smooth and predictable. At your skill level the stability control, even in Track Mode, may be adding perhaps a second to your lap times. It was for me.

Bruce H.
10-20-2014, 08:06 PM
I hope Buttonwillow was a blast!

I replaced the damaged tires with full treads, and that way they'd best match the other tires. I take every opportunity to benefit from coaching tips! Some may not entirely work for me, but they're all worth a try. Sounds like you were very fortunate to learn from Redsled...that's awesome!

I'm going to look into the possibility of storing track wheels at Mosport in case I feel the need for more speed! I actually don't just yet, but may need to offer owners of new Z06/07's a goal to strive for next year ;)

I track exclusively in Track mode. I have never once felt ESC engage, but maybe it's indistinguishable unless you get it really out of shape. The TA's ESC is also supposedly uniquely calibrated so maybe it really hasn't engaged because I've never gotten the car out of shape. The XKR's ESC was so sensitive that I did track it with it turned off, and was very comfortable sliding it around where that made it quicker. I was apprehensive about doing that at first, and would be as well with the TA. I should pick a time and track to try that though. Good thought.

SilveRT8
10-20-2014, 10:47 PM
I would be interested in joining you guys but didn't find any info/contacts on your Quebec forum. Please provide if you don't mind.


Here is the site www.viperacr.com,
Go to Track days, info for the 2014 season is shown, but 2015 info will be posted in feb or march, once new dates are secured.