JackOlsen

I have a 1972 911T that has, as they say, 'some mods.' It's got a 1995 993 motor and close-ratio gears in a 1977 915 transaxle. Maybe most importantly, it has the blood, sweat and tears of Tyson Schmidt in it. He was at TRE Motorsports when the car was first built and is now at Hergesheimer Motorsports as their race mechanic.

My home track is Willow Springs in Southern Californiia, the oldest continuously operating road course in North America. My car is street driven year-round, but it's at its most impressive when it's navigating the nine turns of Willow.



Willow is primarily a momentum track. But it's so fast that high-horsepower cars tend to occupy the really high spots when it comes to lap times. My car has 272 hp at the crank, more or less, which is probably its biggest limitation when I drive it at Willow.

The car is pretty fast through all of the corners at Willow, with the pedal flat through turn 8 and close to flat through most of turn 2. The cornering speed of the car is the result of the work Tyson Schmidt and TRE did on the suspension -- we changed the geometry of a lot of the front end and did the usual ERP/Smart-Racing/Elephant tricks in the back. Tyson also found a way to move the drivetrain forward almost 1-1/2" to improve the car's weight distribution.

I've also made some contribution (with a number of Pelicanites' help) to the car's speed through the faster turns at Willow with a collection of home-spun aero pieces. I've got a 70" wing in the back that's made out of aluminum and beer cooler foam. I have an aluminum front air dam and splitter that I glued and riveted together and some Home-Depot-sourced side curtains to keep as much air from moving underneath the car as possible.

With 13 years of practice, I've gotten my lap times down to a low 1:27 at Willow. That's respectable, given my car. But there are MANY faster 911s at Willow. Maybe the primary distinctions for my car would be when you compare it to other cars of similar power and weight.

But here's the thing. I recently started adding speed (and other) data to my in-car videos, and it gives me an interesting way to compare the car's performance, even with cars that are significantly faster than me. Now, there aren't a lot of data-overlaid laps out there, so my data sample is kind of happenstanc-y. But today I was looking at a decent lap from an IMSA GT3 Cup car at Willow which was posted on Youtube 5 years ago. It's got data on it, so I'm able to look at its 1:25 lap and compare it to my own 1:27 lap. I'm assuming the cup car is a 996 model, because of the date. If that's the case, then it's a 390-hp car (to my 272 hp) that weighs 2500 pounds wet (to my 2420 pounds). It has a MUCH more sophisticated motorsports suspension and is no doubt running slicks for this lap. My suspension is not Weissach's latest -- it's the old 1960s-conceived semi-trailing-arm rear design and the MacPhersons-would-mean-the-golf-clubs-wouldn't-fit front end setup.

But with Tyson's mods.

(And TRE, and Wevo and Elephant Racing, and ERP, and a little Smart Racing...)

Here are the videos I'm comparing.

IMSA GT3 Cup Car guy driving his 1:25.53:


Jack driving his 1:27.04:


It's no surprise that the Cup car is faster than me around the track. And it's no surprise that it destroys me on both the front and back straights. It gets up to about 147 on the front straight, and 142 going into turn 8. I'm lucky to get to 132 mph in either of those spots.

And we're on par through turn 9 -- each a little better than 100 mph at the apex.

But aside from that it gets weird. I'm just about 10 mph faster than him through the turn 1 left-hander. He drops down to 80 mph there and I go down to 90. Then I'm 4 or 5 mph faster than him through the long turn 2 sweeper, measuring by the speed at the slowest point in the arc. I drop down to 67 mph for turn 3, but he goes down to below 60 mph. He slows to about 52 mph for turn 4, while I'm never slower than 61 mph. For turn 5, he brakes down to 60 mph, while I only have to slow down to 70 mph.

Now, for every little piece of straightaway between these corners, he gets up to a much higher top speed than me. So you can make the argument that he doesn't need to go any faster through the corners -- he's already got me beat. But I'm still surprised by the difference in so many of the corners between a race-purpose GT3 Cup on one-day slicks and me on the tires I take to the 7-11 and use for at least a year at a stretch.

Disclaimers? Sure. The really fast guys keep their data to themselves. So I know that there are loads of race Porsches running even faster laps than this guy, even though I don't have access to a video of a lap with their specific speeds overlaid. I'm sure they're kicking my butt in every corner of the track.

But still...

Are the new cars faster? Of course. Porsche makes a great race car and continues to improve the 911 every year.

But it's really amazing to me how the engineering done in the first decade of the car's 50 years of development holds up as well as it does.

And the point of the post?

Not much more than that. I'm surprised by how well an old car can go on a track like this.

What's next?

My only shot at improving on the 1:27 will be this winter, from mid December to January, when my little engine does its best with the colder, denser air in Rosamond. The easy way to go faster would be to throw on a pair of slicks, or even very sticky R compounds. But I've changed from Bilstein rear shocks to Öhlins, and have been pestering Hayden Burvill at Wevo (who had the shocks configured to his own specifications) for the best ways to shake down the new rear end to hopefully get a 1:26 (even a 1:25?) this winter on the same Nitto NT01 tires.

Hayden got Jay Leno to 200 mph in a Carrera GT at Talladega, after all. So if he can get me over 100 mph through turn 2, or to 108 mph at the apex of turn 9... Well, I just might be able to catch that Cup Car.

And then make my street-legal drive back home along Angeles Crest Highway on the same tires.

winders

Chalk it up to a poorly driven Cup Car and the fact that the "Big Track" at Willow is not at all technical.

Cup Cars, especially the newer 997 variety, are much faster than your car.

What are your best times at Sears Point and Thunderhill? I bet decently driven Cup Cars are 10 seconds a lap faster than your car at those venues.

jdistefa

Jack,

Your reference cup video is a gen1 997 cup driven by Brent Holden. Pretty competent guy at the wheel of a 7-cup, if memory serves his best IMSA year was '09.

Your car, although archaic, has a lot of rubber on the road, and is piloted by a good shoe who knows that track inside-out. I'm not surprised by the limited delta.

I suspect that at big boy tracks like Road America, Road Atlanta, Watkins Glen, Mosport, Laguna... the time difference would be more significant all things (i.e. driver) being equal.

Enjoyed your musings though

Nizer

Great looking car.

JackOlsen

Thanks.

Winders, my point isn't that my car is faster than a Cup Car. It's not. I thought I was clear about that. What surprised me was that a Cup Car running a lower lap time than me was still not hitting my cornering speeds.

Here's James Sofronas driving a 996 Cup Car -- so, no slouch at the wheel -- and also running a 1:25.1. He matches my corner speed for Turn 1, but is slower than my car in 2, 3, 4, 5 and 9 during his quickest lap.



Now, for the sake of clarity: Sofronas (who's 10x the driver I'll ever be) has also driven a 1:19 at Willow in a WC Cup Car on Michelin Blues. It's safe to say he's putting me into the ground on every corner with that. But I don't have the data to see how thoroughly he's doing it.

At any kind of real horsepower track -- anything with a 5th-to-2nd corner before a straight -- I'm dead meat compared to most modern cars. There's no way around that.

What surprises me are the cornering speeds. I can see why that would be the case with today's street cars -- they're heavy -- but Cup Cars are pretty close to my 911 in weight. If you'd asked me before I saw this data, I would have said the difference in cornering speed would be much greater, and 100% in their favor.

Nizer

What are you running for tires on track?

JackOlsen

They're the same ones I run everywhere. Nitto NT01 in 255/275.

winders

Again, let's get your car on a more technical track and then let's see what the delta is. What are your best times at Sear Point or Thunderhill?

mehoff

Best frame of reference for your potential track times is to look at the club racers.

POC's typical class leading cars are qualifying at:

9.01:1 --> 1:24's (but on slicks)
11.01:1 --> 1:27-1:28's (rComps)

You need to address your motor; running the "as-delivered" 272hp to the crank is a sin. Tack a vario on there, decent headers/exhaust and proper tuning and the car will easily achieve 270-280bhp. Then you're off and running!

Wish I had that car to drive on the street.

67King

How would a more technical track better tell the capabilities of the car? Seems to me a less technical track would be better, as driver capability is less of a factor.

Stunning car, BTW.

Rob in VA

I'd chalk it up to - guys w/ bigger hp cars tend to overslow the car because they aren't as good w/ the brake pedal and/or their butt dyno screams at them to slow the eff down. lol

winders

Less technical tracks demand less of the car.....they reduce the difference the suspension advances of the last 40 years make in lap times. Willow Springs is a terrible track to use to compare differences in cars.

JackOlsen

The delta is huge, because you and I completely agree on one point: my 1972 911 is not as fast as a Cup Car.

I haven't been to the northern tracks in about seven years. I ran a 1:59 when I was last at Thunderhill. I know that would be a very, very slow time for a cup car. Horsepower plays a very big role at Thunderhill, and I ain't got much of that.

What's interesting to me is this: if I put my car and a Cup Car on a flat piece of asphalt and scribed out a big circle and just looked at steady-state cornering, somewhere in the 100-mph range, and the Cup Car was on its DOT-be-damned tires and I was on my well-used Nittos, I would expect the Cup Car would be significantly faster -- because of the suspension design and the tires. Now, Willow isn't a flat piece of asphalt and I'm not looking at the speeds at very many points in a given corner. It's possible that a Cup car is set up to go through a whole corner faster than my car even when it drops to a lower speed than mine at the slow part of that corner. That's entirely possible.

But I'm surprised by these two better-than-me drivers, in both a 996 and 997 Cup, dropping to lower speeds than me at so many points on the track. Of course, even with that they're running quicker laps than me. And a 1:20 lap is possible with some variant of these cars, so I might just be looking at cars that haven't been dialed in by their crews at all.

But the point of the poast was pretty simple: I was surprised by what I saw.

JackOlsen

I did another search on YouTube, and found James Sofronas again, this time in the GMG Racing WC Spec Audi R8. He runs a high 1:19 in this clip, and his cornering speeds are the closest I've found to mine. Which is to say, he's much, much faster than me -- but still drops down to lower speeds than I do in some of the corners. Since he's more than 7 full seconds faster than me, maybe I should take that delta with a grain of salt.

Jump to 2:54 to see his fast lap:



On the front straight, he gets up to 151 -- I only get to 132.
In turn 1, he drops to 91 -- I drop to 90.
In turn 2, he drops to 95 -- I drop to 96.
In turn 3, he drops to 62 -- I drop to 67.
In turn 4, he drops to 61 -- I drop to 61 too.
In turn 5, he drops to 67 -- I drop to 71.
On the back straight, he gets up to 152 -- I only get to 132.
In turn 9, he drops to 109 (which is amazing) -- I drop to 105.

Now, the really meaningful thing is that he goes much faster from corner exits to the next braking zone. And I would assume he also comes into the corners faster, no doubt giving him a higher average speed through each corner when you look at the bigger picture. It's clearly not just the straights where he's faster than me.

But still, I've got to wonder why it's necessary in a car like that to slow down for the sake of a faster overall corner. As I said, it could be that I'm simply looking at a particularly unimportant piece of data.

333pg333

As the title of the thread relates to corner speed then the speed differences are unambiguous. Comparing your corner speeds to that of a Cup is fine. Especially on a 'less technical track' as the purportedly weaker Cup driver isn't disadvantaged by his assumed lack of ability as much as he might be on a more difficult track. ie the weaker driver won't be much slower in the corners than the Pro on this sort of track. To add, while the NT01 is a pretty good tyre, but it's certainly not the fastest R spec available and to compare to a Cup car on Slicks is excellent.
Congrats Jack for your persistence...in many respects...