jbossolo

I don't care how fast your car is Jack. It simply is the most beautiful car on RL. I'd trade all my 4 cars and my left ******** for it. Just wanted you to know that.

9.5 Degrees

+1. It looks like a labor of love. Seen Jack's videos on how to drive willow springs and his garage etc. so envious of the time and creativity he has for this hobby of ours.

jdistefa

...And self directed learning can have higher value re. retention and understanding. It's just a time:efficiency thing.

turbochad

It is certainly possible that Jack's car is developed enough and runs enough tire to compare to say, for example, a GTC4 car on a skidpad but my money would be that it wouldn't. I know that as compared to my E class car running on Hoosiers that GTC4 cars generate about +.3 more lateral G's in low speed corners. If stock classes were allowed to run slicks the delta would close.

I agree that if old cars were running the same spring rates and tires as modern cars they would produce similar results on a skidpad. At that point an old car is not really an old car is it?

That is part of the reason that Jack's car is so cool and loved. It looks like an old car, but really it relies heavily on information and changes that have been achieved over the many years since it was manufactured. This is the reason that with minimal performance enhancing rules changes in Club Racing the track records continue to fall every year. Those people who follow trends in racing engineering find ways to improve the performance of their cars, legally, without rules changes, while those who don't fall further and further behind. The same is the case in all forms of racing. You can freeze the rules and the cars will keep getting faster.

Jack's examples just illustrate the power of development of both the driver and the car, together. Most people don't have the knowledge or the patience to do this kind of work in club racing. If Jack were to go club racing, say in E class, I would think he would do very well because it is a class that rewards both good driving and ingenuity in car development. If he were to go racing in SPB then his driving skills would play a larger role than his ingenuity as compared to the stock classes. Still there is a difference in car development in SBP between the top 3 cars and everyone else just not as much.

Same spec does not equal same car, but I digress.

This is a fun thread, thanks Jack.

claykos

First of all - 1:26s or 7s is absolutely flying at Willow in a car like that.

I didn't read every post in this thread, so maybe it was already mentioned, but minimum speed in a corner is not incredibly meaningful when comparing two cars with radically different amounts of power. I have quite a bit of seat time in cars ranging from ~235 rwhp to 600 rwhp. These include an early chassis 911 with the same stock 3.6 (~240 rwhp) as Jack's car, as well as an early chassis 911 with ~360 rwhp, and a 996 with ~400 rwhp.

The big difference between these cars is the changes in handling dynamics when on/off throttle. My old 911 with huge tires and 240 rwhp had almost no change in over/understeer characteristic when I was on or off throttle. That meant huge mid corner speed since picking up the throttle from apex did little to change the balance of the car. In what was basically the same car suspension/tire wise, but with 360 rwhp, picking up the throttle even slightly would radically change the balance of the car. This meant I was usually a tick slower mid corner because I was doing the balancing act of throttle/turning much more delicately than with the lower powered car.

Now maybe a better shoe than I could have kept identical mid corner speed and gone even faster, but I guess I'm just trying to say that comparing minimum corner speed from two cars with hugely discrepant HP levels (and therefore entry speed at the brake point as well as longitudinal accel on exit) doesn't really tell you too much about the relative capabilities of each car.

ProCoach

No, but it does tell you a lot about the relative capabilities of each driver!

JackOlsen

Thank you, guys. I do have more laps than most drivers at Willow Springs -- which I can chalk up to my advancing age, general hard-headedness, and the robustness of the 911 platform. The car just won't break, so I keep bringing it out for more.

I agree about the relatively insignificant value of the lowest speed through a corner. At least, now that I've looked at so many much-faster cars who drop down to lower speeds than me, it's become very apparent that it's just not a very important metric. James Sofronas has gotten down to 1:17s at Willow Springs, which is a full ten seconds faster than me. It might be that he has several points on the track where he's going slower than me in one of my fast laps, but that does absolutely nothing to change the fact that he's ten full seconds faster than me.

I'll admit, I'm still surprised that there is ANY point on the track where Mr. Sofronas in his WC Spec R8 is going slower than me in my street car. But there you have it. And again -- the pro is ten full seconds faster than me (which is huge, especially at Willow).

And I'll admit that The Audi race car and my 911 have closer segment times than I would have ever imagined in that small piece of the track I sampled. Granted, it's a segment where the horsepower of the audi is not rewarded and its weight (what does it weigh, anyway?) works against it. But still, it surprised me.


The reason I was looking at Cup Cars and other race models and their lap speeds was because I'm in a position where I need to increase my cornering speeds if I'm going to lower my lap times. Of course, that means I've got to get through the whole corners more quickly -- not just drop down to low speeds that are less low. But this was one area I started looking at, and I started a thread because I was surprised by the results.

When it became clear that my low-speed figures was probably a red herring for improving my lap times, I started another thread,, and got some more very useful information (including a post from Sofronas himself) there.

In the course of these threads, I've learned a little about the modern Porsche race cars and how their characteristics are (necessarily) different than my 1972 911. I hope one day my life takes a turn where I get to drive one of them. I've driven several different generations of GT3s (and other fast road cars) in the course of instructing, but the sad fact is that not many Cup Car owners are looking for my instruction.