When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
For what it's worth here's an interesting comparison. I take the traditional entry and worked hard with Peter Krause to make sure I am at 1G continuous at the entry to Big Bend and not leaving time after max braking for coasting. It would appear that this line is 1.4 seconds faster by the apex of the right hander. Improving that section alone could almost put you under 1:00.
Were these supposed to be videos? I only see frozen pics.
Were these supposed to be videos? I only see frozen pics.
They are screen shots from videos. The point is the time. They are both at the same point on the track, but I'm there at 23.6 secs and he's there at 25.0 seconds. I did that in an R on Yoko's and he's in a GT4 on MPSC2s. Point is there is a ton of time to be gained in the slowest and shortest part of the track, and based on my work with Peter I think the majority of that time comes in the entry to Big Bend or in the first 500 feet of a lap.
The actual video is in the first post of this thread for Paradocs lap and my video is in the thread "Shout Out for Pro Coach".
1. More shifting. up and down. That alone will find you a second, easily! you are leaving 50-60hp on the table in many places, and downshifting for a few of the turns will allow the LSD to work for you more too.
2. keep hands at 2-10 and feel the car on the exits and entry of each turn
Edit: the difference between running in the 4500rpm to 5500rpm range vs the 5500rpm to 7500rpm is a SOLID 50hp . To put this in perspective, you bought a car that has 50hp more than a cayman GTS, yet, with a GTS, you could be actually faster, by just using the gears..PLUS it will make you a better driver. practice downshifting before each turn... shift at the end of the exit birms, rince, repeat.. there is your 1 second VERY easily.
this is advice has nothing to do with changing anything with your driving or the nuances of the track. just basic track 101 stuff.
Originally Posted by winders
Ever hear of Sears Point (Sonoma Raceway)?
I know huh!!!!
Originally Posted by paradocs98
Yep. I think the West coast guys sometimes don't appreciate the limited runoff of places like LRP and the Glen.
turn off the nannies... as winders said, it only gives you a false sense of security, and when you turn them off you will have to learn the car all over again.
just back your driving down a notch.. find the limits on the safe turns , entries and exits at the slower speeds. this is the best way to be safe in the end. 20 track days is more than enough time to do this at the track. in fact, i think its much better to never engage the nannies at the track. you will never learn from the mistakes, NEVER.. (mistakes dont = crash... mistakes = car over the limit of capability ) 100s of little mistakes are masked with the nanny..... that part is the most important part of learning the track and the car.
Last edited by mark kibort; 09-21-2016 at 01:00 PM.
For what it's worth here's an interesting comparison. I take the traditional entry and worked hard with Peter Krause to make sure I am at 1G continuous at the entry to Big Bend and not leaving time after max braking for coasting. It would appear that this line is 1.4 seconds faster by the apex of the right hander. Improving that section alone could almost put you under 1:00.
And in both of those pictures, going on to the straight sections , i would say there is another full second a lap lurking there too by dropping down a gear and exiting the sweepers at 5500 rather than 4500rpm. (particularly at the 24 second mark on the JP66 video)
Have you driven this track at a competitive speed?
Best, Peter
__________________ -Peter Krause www.peterkrause.net www.gofasternow.com
"Combining the Art and Science of Driving Fast!"
Specializing in Professional, Private Driver Performance Evaluation and Optimization
Consultation Available Remotely and at VIRginia International Raceway
Have you driven this track at a competitive speed?
An innocent question back at you:
My race car's 3.6L engine redlines at 7,000 RPM and I know if I am below 5,000 RPM it is a total dog accelerating out of a corner.
Now, I don't own nor have I driven a GT4 so I don't know its power band. But I understand that redline in 2nd gear you will going 83 MPH. So I am guessing the stills from those vids have the drivers going 66 in 3rd gear at 4,782 RPM.
Considering the redline of the GT4 (isn't it 7,600 RPM), it would seem that Mark would have a point here. Wouldn't going 66 MPH at around 6,100 RPM be better?
Have you driven this track at a competitive speed?
Best, Peter
Peter, Im only pointing out something i know about, and that's engine performance as it relates to acceleration on the track, and staying very general and textbook about the track. (straight line acceleration only.) If you or anyone tries it, and it and it doesnt pay off, nothing lost. But there is NO reason at all to not utilze the engines performance . certainly, at least at that one point about 24 seconds in. running the car at 50hp below its capability at points on the track where you are WOT, is wasting time in my opinion.
Now, if the driver cant modulate the throttle until max grip is available, then instead of short shifting, (if thats your concern) then its time to practice doing that!
the main goal is to redline on to the approach to every turn if possible and start out at near max HP as soon as possible as well. (i.e. 6000 to 7500rpm and NOT 4800 to 6000rpm which is a 50-60hp delta for a substantial amount of time.
Some here will focus on lines and some focus on car performance. since i only have the video to go on to comment on lines and many others have driven the track, ill focus on things that seem obvious and are track independent.
we all were asked, basically, "what can i do to go faster". i voiced an observation.
Ran at Lime Rock with SCDA yesterday in my GT4, my second time there in this car and probably my 20th time at LRP in the last five years. I consider it my "home" track since it's the closest one to me. I'd like to eventually get under the 1:00 lap mark at this historic track. <snip>
Video of a lap follows--comments welcome. Thanks in advance.
as far as efficient power utilization.. over one lap, i estimated about 23 seconds of where you could be in a lower gear after the exits of the turns, and before 6000rpm to gain a full 50-60hp in that time period. and thats a HUGE amount of time. most ive seen vs the anti-short shifting advice ive given before.
all i did was count the time you exit the turn at WOT, and get up to 6000rpm.
This is because that is the period of time that you could be running from 6000rpm to 7000/7500rpm.
now, what do you think your lap time can be if you gain 50-60hp for near half of an overall lap time?
There is your smoking gun for the 1 second you look for! trust me.. it will be found very easily with this one very simple change.
edit: one full lap is estimated to be about 30 seconds WOT (based on video) you are talking about 75% of your WOT time at 50hp reduction!
Originally Posted by winders
An innocent question back at you:
My race car's 3.6L engine redlines at 7,000 RPM and I know if I am below 5,000 RPM it is a total dog accelerating out of a corner.
Now, I don't own nor have I driven a GT4 so I don't know its power band. But I understand that redline in 2nd gear you will going 83 MPH. So I am guessing the stills from those vids have the drivers going 66 in 3rd gear at 4,782 RPM.
Considering the redline of the GT4 (isn't it 7,600 RPM), it would seem that Mark would have a point here. Wouldn't going 66 MPH at around 6,100 RPM be better?
since you run one of the most technical tracks in the country, as fast as any new cup car, it would be interesting to see what shifting in that lower range would do to your times. i bet you lose 1-2 seconds very easily!
oh, but maybe not, because sears has no turns or runoffs!
powerbands shown below for reference. my advice based on 80% post shift RPM or 85% depending on the gear. in this case its 3-4 which is 80%
(e.g. 7600-6100rpm). in this range you maximize HP utilization. at 4800 to 6100rpm, you lose near 50hp
Last edited by mark kibort; 09-21-2016 at 05:02 PM.
Its simple brake later, accelerate earlier and Hit the apexes
With that said I hold lap records there and have never done a perfect lap
Lime Rock is one of those tracks that takes a long long long time to master. Don't forget it feels slow but its one of the fastest tracks in the country in average speed.
P.S> you are doing DE concentrate on doing perfect lines first. Then work on throttle and brake applications forget times for now
Hmmm. Torque band awfully stable and very broad in the GT4 in all RPM ranges likely to be encountered in the corners we're talking about...
Come on, Peter. That is just lazy. You and I both know that the GT4 will pull much better in 2nd gear at 6100 rpm than it will in 3rd gear at 4800 rpm. Power is what matters in acceleration, not torque.
I have no idea if 2nd would be better, but the GT4 will accelerate harder in 2nd in this case than in 3rd.
Hmmm. Torque band awfully stable and very broad in the GT4 in all RPM ranges likely to be encountered in the corners we're talking about...
This is my mission... To help clear up this kind of misnomer. Many get this part of auto racing performance wrong. You have to first understand that engine torque is not REAR wheel torque. If you want to maximize REAR wheel torque, that will happen at max or at the highest HP levels at ANY vehicle speed. This is not something im making up... its basic physics.
remember the law? Acceleration = power/(mass x velocty) or more simply
power = Force x velocty.
If the power goes up, what happens to the force if the speed doesnt change???
RIGHT! it goes up directly proportional... thats why HP curves can be so useful!
so, if you are going 66mph at 4800rpm in the GT4, based on the HP curves, you can downshift and be at 6000rpm and have 50 more HP all the way to redline . as the physics says, whatever that increase in HP gained, will be the gain in the rear wheel forces. This is regardless of the "broadness" or "flatness "or anything else relating to the"engine torque" at the lower RPM
If you review the video, its very easy to get enough data to be conclusive here.
30seconds of full throttle
23 seconds of ful throttle in 3rd gear when 2nd has 50 more HP.
so, thats 23 full seconds of between a high of 60hp more and 20 hp more HP available!! 75% of the time at WOT, can be at a much higher HP level.
I might have saved that second and didnt have to even ride around in the car with the student!
Its simple brake later, accelerate earlier and Hit the apexes
Lime Rock is one of those tracks that takes a long long long time to master. Don't forget it feels slow but its one of the fastest tracks in the country in average speed.
P.S> you are doing DE concentrate on doing perfect lines first. Then work on throttle and brake applications forget times for now
All true. Master the fundamentals and the rest will come.
Funny thing about data and math it can illuminate a lot.
No Name straight is 256 meters of full throttle on my data in a car driven by a professional race car driver. Assuming for a moment one could keep the car in 2nd gear for half that distance what is the difference in time from 256 meters all in 3rd gear versus 128 meters in 2nd and 128 in 3rd ignoring losses for a shift.
distance is 256 or 128
acceleration in 2nd gear is 2.86 m/s/s
acceleration in 3rd gear is 2.16 m/s/s
initial velocity is 67 mph or 30 m/s
I'll spare myself and y'all the math, but the answer is .1s potential time savings now add back the loss for a shift . . . ummm . . . maybe that's why no one I know who has actually driven a modern Porsche at Lime Rock ever shifted down to 2nd gear in the middle of Big Bend.
for those who care I get acceleration from my AIM Solo
09-18-2016, 07:18 PM
