From dirt to pavement and back: Jeff Zwart

Zwart Pikes Peak 2010
"...Tip-toe is a pretty minor word when you consider you're tip-toeing at 80 miles an hour." - Jeff Zwart. Photo by Rupert Berrington
Zwart pikes peak 2010
Driving a 2007 GT3 Cup car, Jeff Zwart beat all production based race cars at the Pikes Peak hillclimb and set a new class record in the process. Photo by Rupert Berrington
Zwart Pikes Peak 2010
After Zwart's success this year, other professional race car drivers, such as Patrick Long and Wolf Henzler, have expressed interest in racing at Pikes Peak. Photo by Rupert Berrington

Jeff Zwart logged an incredible victory at Pikes Peak this year, finishing sixth overall in a normally-aspirated, rear-wheel-drive GT3 Cup. In doing so, he beat every production-based car there as well as all but five purpose-built Pikes Peak racers. It was a stunning performance from Jeff as well as from Porsche’s ubiquitous GT3 Cup — one that may point to more Porsches at Pikes Peak next year.
In the last year or so, Jeff has discovered the charms of our local taqueria, so we were only too happy to meet him there and hear his thoughts on the win as he gulped down his flautas.


In the car with Zwart during his qualifying run.

Excellence: Tell us what you’re thinking about, what you’re looking for as you attack Pikes Peak.
Zwart: You always look for what the grip is right away in the first five corners and kind of read everything from there. We’d done a scrub set of tires, but it’s still between the brakes on the car and the tires. You gotta kinda get ’em up to temperature, but there’s really no room to get them up to temperature.

Excellence: Tell us what a scrub set is…
Zwart: A scrub set would be one run on a brand new set of tires so it just takes the nubs off, takes the edges off slightly, that sort of thing. So it kinda gets you a little closer to the optimum compact level. So you use the first five turns to set the car, figure how much it’s really gripping, figure out what the conditions are, because all our practices, we were off the mountain by 8:00 (AM). On race day, I wasn’t running ’til about 10:30 or 11:00.

Excellence: What was the temperature difference?
Zwart: So it was about 30 degrees difference in temperature. We knew that there were a few unknowns given the temperature, including engine and everything else. So, I headed up the road, the grip is really good, all that stuff. I’m running on a racing rain (tire); as soon as the things dry out, people get rid of them, for good reason. But I needed them for the dirt, and really – the mountain – it’s really built upside-down for what you need in terms of tires. You need the tread and the grip and everything at the top, and you need the smooth tire – the racing tire – on the bottom. And because of that, I figured out I am absolutely going to restrict myself from sliding, all the way up the bottom. I know it looks really boring.

Excellence: But would you be faster?
Zwart: You know, the problem is, yeah, you’d probably be faster, but you’d be increasingly slower as you got up towards the top, ’cause you know tires will start to ball up, start to roll the rubber off and lay the rubber right on top of (itself), and it’s not a good feeling at all.

My goal was to get up there, get to that first section of dirt not sliding at all. I did that and just carried lots of speed everywhere. (I) didn’t go quite as fast in a couple high-speed sections as I had in the practice, but that’s because in practice you run over and over again and kinda know 15 minutes earlier the course was good.

You gotta remember, when you take off on this course, there’s no flagman there waving a red and yellow flag saying there’s gravel on the course, or anything like that. There’s no flagmen telling you what to do. And all you need is a couple guys ahead of you ditch-hooking, and suddenly the whole corner that you’re committed to is covered in gravel. So you really have to watch that sort of thing.

And so I ran the bottom, ran really smooth, just carrying a lot of speed, then went (into) the dirt. In the dirt, you really have to attack; you have to really be on top of it. If you kinda wuss around, your car ends up pushing everywhere and it ends up not feeling like it handles very well. I drove real hard on that.

Then I got back to the pavement and that was all the “Ws,” which is all first gear. I think there are seven first-gear hairpins at the base of the mountain. You go up about 2,000, 3,000 feet or something at the base of the mountain. And I could just feel every hairpin, you know. Hairpin five, it started skatin’ a lot in the rear. Hairpin six it just started getting real greasy, so I knew I had really gotten the tires right up to the maximum temperature. But I thought if I could just maintain that and hit the next section of the dirt, which is all the high-speed stuff, it’ll be terrific grip, everything will be good. So I backed out on the next hairpin just to make sure that I didn’t get it too balled up. And then when I hit the dirt there, I’d never gotten through the top section so fast.

Excellence: Talk about the transition, when you hit the dirt from pavement.
Zwart: I’ve driven a lot of cars with a lot of different tires, a lot of different ideas on how we should be set up, and I gotta say, the Pirelli rain tire was – this is how I’d describe it – it’s super compliant going from surface to surface. And what’s really great is it consistently gives you the same feedback, whether you’re on pavement or dirt or gravel, in terms of how the car feels – under braking, when it breaks loose, slides. Normally a tire has an entirely different feel on the dirt. Usually, when a tire breaks loose on pavement, it’s a big hop – it goes away real quick. (The Pirelli rain tire) was very, very … I’d almost call it supple – the feel to it, the way it would break loose on the pavement. It was so compliant surface to surface.

So I’m getting the same feedback from the tire on all the surfaces, but obviously experiencing different levels of grip. It’s slipping differently everywhere, but the feedback is exactly the same.

Excellence: Would you credit that to sidewall construction or rubber compound?
Zwart: Compounding.

Excellence: Are the Pirelli rains significantly different in sidewall construction from a dry tire?
Zwart: All I’ve had experience with is running DOT tires there, so I can’t answer from tire to tire that way. I just know from the experience of driving, the Pirelli was the best tire I had ever experienced there. Just unbelievable.

Excellence: In previous attempts, was Rhys Millen’s attempt on road-racing rains or on DOT tires?
Zwart: We typically ran a drag radial. We look for a tire that’s gonna last 12 miles and a drag radial was good for that. One of the biggest problems was getting (heat) into the tire early enough. So you want a tread block that moves quite a bit, so it heats up. And you run that way. So that’s important. That’s where the drag radial in a DOT world worked real well. But they were probably too soft for us.

When you look at a rear-engine Porsche, (with) all the weight and power trying to be put down over those wheels, a drag radial was pretty shredded. Still a very good tire, but we could never balance the car with a drag radial front and rear. We’d run a (BF Goodrich) R1 or something up front and a drag radial on the back. So you’d never have the balance you would with identical front and rear compounds.

Excellence: That had to make for a huge amount of difference to feedback…
Zwart: Mmmhmm (yes). We’re driving a Cup car, so everything’s known about it. It’s already so well developed, so when Pirelli says, “We want you to run this tire,” they have a vast amount of experience with running that tire on Cup cars.

Excellence: What was left of those tires by the time you got to the top of the hill, since you’re going on rains that are designed for road racing and endurance?
Zwart: I could’ve done another run.

Excellence: With no detriment?
Zwart: With no detriment. I mean, they were seriously the perfect tire combo. I’ve never, ever seen it. You can run really hard on the bottom, but you won’t have enough left on the top. I had the perfect tread depth for encountering what surfaces I needed to encounter. And yet the last new mile of pavement, I could go flat through the double left and all that stuff I’ve always had to lift for because I would have no tire left.

Excellence: Do the pavement changes this year affect your time, and how so?
Zwart: No. The pavement changes this year were offset by the dirt being a little worse. As of Monday, right after the race, they were starting to pave the two miles at the top. So they had already prepped the ground in kind of not a hard-packed way. So yes, we had one mile of additional pavement at the finish that we haven’t had in the past, but I believe that the advantage gained by that one mile was offset by the condition of the roads just below it.

Excellence: It’s always hard to compare lap times, track times – anything – year-to-year. Laguna Seca, Le Mans, Sebring especially. At Pikes Peak, how does that figure?
Zwart: There are so many variables at Pikes Peak. First of all, we practice it in thirds. So we never put the whole mountain together until race day. And then on race day, you’re dealing with three to four hours later than your practice times, so you’re dealing with 30° differences in temperatures. You have weather issues. While I was on top of the mountain I saw rain, hail, snow, sleet – everything – while I was up there waiting after I had made my run – that other competitors had to run through.

There are so many variables there, and I guess that I look at it from run to run; you don’t know how the surface is gonna hold up. All you need is a big stock car or an open-wheeler to go through a corner, and wherever he was is the part that was swept clean. But it might be entirely different from the time before. So when you enter a corner you are constantly making little adjustments inside, outside, to try to put at least two rear wheels – the drive wheels – into that area. And the same goes for braking. I’ve literally moved the braking zone over two car widths because suddenly one side got cleaner than the other.

Excellence: How much can you feel and how much can you see in the surface? How well can you read the surface?
Zwart: It’s 50/50. To go fast at Pikes Peak, you have to go way beyond what you can see. So a lot of times once you’ve arrived on the point, you’re making those adjustments inside, out, at the rear wheels. And you know, you’re hating life. It’s a great show – there’s one thing on YouTube, actually, that shows me doing this – you’re hating life when you end up wide somewhere and you’re just spinning your wheels in an amazing drift, you’re all sideways, and it looks great inside and outside the car. But inside my head I’m hating life because I know I’m losing time there. And the problem is if I don’t have an all-wheel-drive car, I really can’t get it back to where I want to be, so you’re kind of committed to, “Okay, I’ve gotta keep the car out of the ditch,” but you can’t move it back over, into the sticky part.

Excellence: You beat Rhys Millen’s time by 38 seconds, which is just staggering and far beyond what you had hoped for. Say you had a perfect run, saw the perfect line all the way up, and not had to make too many adjustments… How much time was left on the table?
Zwart: I think that – we had a discussion about this yesterday, actually, Paul Ritchie (President of Porsche Motorsport North America) and I – I don’t think it would be too hard to think that I could go a second a mile faster. Which is 12 seconds. So I could be in the 11:15, 11:17 with the set up of the car there.

Excellence: Where would that place you amongst the open wheelers?
Zwart: One position (up).

Excellence: So there’s quite a gulf between you and the top four finishers, but we are talking about a production-based race car that came off an assembly line. It’s not a race car that has been Pratt & Miller-ized, but it’s something that is a real production race car.
Zwart: It’s funny, ’cause the Australians, everybody’s kinda congratulating me, because we really ended up way up in the field, further than anybody ever expected. And the Australian guys, when they were leaving, said: “You have the fastest tin-top up here!”

Excellence: Tell me about the engine. It’s a grouping of parts from various series because you didn’t have to deal so much with the rules.
Zwart: I bought the car at Sebring from Lloyd Hoffman, and it went to Porsche Motorsport North America and they basically looked at the rules – we all looked at the rules together – and said, “What can we do?” And they brought it to 2010 spec. So it’s a 2010 motor; it’s a 3.8 instead of the 3.6.

Excellence: Tell us about the transmission.
Zwart: I did the transmission, which meant I put in short gears so it had a 125-mph top speed. It was kind of a big deal because nobody needs a 125-mph Cup car. It was actually fairly costly.

Excellence: But obviously worth it — because the transmission is one of the things you pointed to as a defining aspect of that car.
Zwart: See, what I knew is, I’m going there without a turbo, so I’m gonna be 30 percent down on power. I’m gonna be running against Mitsubishi Evos with 600 horsepower, all-wheel-drive cars, all different cars, so where can I get an advantage?

Excellence: But it’s not really power that’s the issue, it’s torque.
Zwart: But if you look at it, I have a 48-mph first (gear), which meant I had five more gears to the top speed – just 75 miles per hour. So that meant that I could carry that engine in the sweet spot with a drop of only about 1000 rpm each shift. So I could carry the engine in the sweet spot all the time. And then with the sequential gearbox shifting so fast, the car would not change attitude when it was sliding, it wouldn’t lose momentum when you were going uphill, all those things. I felt that was my key to offsetting the lack of turbos; it was by keeping the engine in that spot and just never being below, basically, that range where I get the most power.

Excellence: Now, you ran a used 2007 GT3 Cup – they’re certainly out there – updated to 2010 specs on the engine. Was it updated to 2010 specs on anything else?
Zwart: No.

Excellence: Do you think the 2010 GT3 Cup’s upgrades in terms of wider fenders, wider track, different wheels would have been beneficial to your run?
Zwart: Not the way the surface is currently because we almost have too wide of rear tires for the gravel as it is. They float quite a bit on top of the gravel, so because of that you kinda wanna dig in a little bit.

You have so few runs at Pikes Peak, if you have a good car – and I had a great car – so you put your head down, you think about attack, you think about carrying speed, you think about being good to your tires, that’s all gonna make up for more time than a 2010 upgrade. I had the motor behind me, I knew that.

But in terms of all these little tweaks, we could come back and change sway bars, and change cambers, and all that stuff. But you have so few runs, and it’s so hard to determine anything because of the lack of consistency of the surface. Your mind has to be in the driving, and that’s what’ll give you the most time on the table. You see it constantly at Pikes Peak, or any race. What do you want: A car with 700 horsepower running at 80 percent and having all these issues with it? Or do you want a car with 500 horsepower running 100 percent? (The latter is) what you want. And that’s where the car gave me so much confidence; it never bit me, it never did anything funny.

You talk about carrying speed, there are so many combinations of turns. I’d get through a series of turns and – you don’t want to think about it too much but – it would occur to me, “Whoa! I just floated through there!” No big braking, no big steering inputs; just by taking these lines, which is basically a road-racing line, and letting that car float, it would get through so fast.

Excellence: How much did the 911’s inherent rear engine, rear-wheel traction come into play with that?
Zwart: That’s a little bit of a misnomer in a 911. I’ve previously run nine different cars. Eight of them were four-wheel-drive cars. Four-wheel-drive’s great, it sounds like it’s the perfect thing at Pikes Peak – and I agree that it’s a really good thing – but the advantages of it compared to a traditional four-wheel-drive rally car is, your wheels can’t do anything unless they have weight on them.

Let’s think of first gear hairpins; going uphill, accelerating, you’re just not going to have any weight on the front wheels to really put power down with. When I ran the manual torque-split car, I dialed it way back so it was mostly a rear-torque car. Because otherwise it was too much torque going to the front wheels – you’re gonna have it push like crazy. And Pikes Peak is the last place you want to have push. It’ll push you right off the edge of the mountain. You wanna have that little lift that dances the rear out, tightens it up. That’s what you want. I think that that’s where it is.

Excellence: And how about the rear-engine, rear-wheel-drive Porsche against the Mitsubishi Evo?
Zwart: When you go back to the other side of it, I’ve got my power sitting over the top of my rear wheels, so if I have a good handling car, it’s gonna be great. That’s where it does work really well. If you look at the stock cars and some of those cars that run there, they run very, very quick. (Yet) this is the first year the production-based cars have ever beat the stock cars. But you look at how those run, they don’t have the weight (over the rear wheels). They just have monster horsepower and drivers that know the mountain.

Excellence: Did any other production cars beat the stock cars?
Zwart: No. Only me. It’s funny because you’ve got stock-car drivers like Clint Vahsholtz, they basically own the mountain. I think he has 15 championships. He even won one on a bike. He is master of the place. And after the race, he asked “What’s the deal with this car?” Everybody was wanting to know about it.

Excellence: Patrick Long, Wolf Henzler, and some others have expressed interest in racing at Pikes Peak next year. Have you heard about this?
Zwart: I told Paul (Ritchie) the first day, I said: “Here’s the deal. We might get a lot of press for next year,” ’cause everybody was talking to me about the RSR and saying run an unrestricted RSR with the lighter weight, more horsepower, all that stuff that they do really well. I said, “Well let’s just come back, enter the time-attack class just like we did this year, but we have Wolf start. I’ll be standing at the edge of the dirt, and we’ll do a driver change. I run the dirt, and then Patrick finishes the top on the pavement.” I said, now there’s an idea!

Excellence: You own several Porsches, and you’ve driven too many to count. Today, you showed up in a ’53 356 that you drive in the snow, on its original 16-inch wheels and tires.
Zwart: I drove up today in a little Pre-A coupe, and it’s just such an original basic coupe. And I drive it on gravel roads and everywhere. I figure that each day I try to get sideways somewhere, and it doesn’t matter if I’m driving the ’53 coupe or the GT3 RS; I don’t really care. A good day is when the traction light goes on.

I have a mix of cars, and the thing is, I always joke that in a Porsche you can tell how fast you’ll be driving by how thick the steering wheel is. And it’s pretty much true. If you drop into the ’53, you know you will just need to pace that thing.

That’s what’s great about Porsches — they’re somewhat quirky, all of them. And so they develop you as a driver. You don’t go out and in the first ten minutes, peak in that car. It takes you awhile to develop yourself, to go faster, to understand the inputs and the responses it gives you. It develops you as a driver. There are plenty of good cars out there and I’ve driven a lot of them – the (Nissan) GT-R’s a good example. You can go fast in that thing right away, whereas you gotta be good and you gotta up your game in all these different cars.

After the GT3 RS, the GT3 Cup felt like home right away. Obviously the instrument cluster is all different, the seating position is a little different, and things like that. But actually the week before the event this year, I just worked every road car I drove, sitting really, really low in it. Typically, in a rally car, you want to sit up as high as possible, but I knew in the Cup that wasn’t really possible. So I got kinda used to my point of view in there.

Once you took the feedback (the GT3 Cup) gave you, the first time I came into something a little bit fast, it did everything I expect of a traditional Porsche. And therefore I could go fast. People said “What about the sequential box?” and even Porsche kind of warned me about the sequential box. I had a five-minute (learning curve). Sure, I stalled it the first time I pulled it out of the trailer, but after that it seemed completely normal.

Excellence: So when’s a sequential going in the 356?
Zwart: (Laughs) We’ll see. Never have I been more impressed with a single element of a car than the sequential gearbox. Then imagine having that entire transmission in almost half the speed range of a normal one. The data showed 128 shifts.

Excellence: You mentioned every Porsche has a quirk, so what’s the quirk of your 906?
Zwart: The quirk is getting yourself out of it! (Laughs). The 906, for its size of tire, is a lot of car. That’s a pretty skinny little tire that car goes out on. One thing that – I wouldn’t call it a quirk, but it’s something that is quite amazing – you just don’t get a chance in our modern-day lives to drive is something with slightly over 200 horsepower that only weighs 1,400 pounds. And I think there is no substitution for lightness. You can never make a heavy car feel light once you’ve experienced something like that. So that’s probably its quirk.

Excellence: And then you have a 36,000-mile, ’08 GT3 RS. You’ve put a ton of miles on it going to photo locations, all over the country and the west. What’s the quirk with that car?
Zwart: The quirk with that car is understanding how fast you can go. I can see how people can get in trouble in it. You see the traction light come on over every crest, you feel it just dig deep when you come out of tight corners and over rough sections. It’s just phenomenal how fast it is and you need to be on top of your game, especially in braking zones.

And that’s one thing I learned at Pikes Peak this year; I mentally have braking zones there, and you’re used to having braking zones at a road race – I mean, virtually every driver does – but what happened was, it was somewhat deceiving how fast I could go in (the GT3 Cup), and one thing you can’t change is how long it’s gonna take to stop the car. And so I had to constantly adjust my braking zones there because I carried so much more speed. Even run to run.

At a track, especially such as Pikes Peak where there’s only one clean line, you hate life – at least I do – I hate life when I end up wide because I’m out there in the slippery stuff, I can’t put the power down, and that all occurred ’cause I went a millisecond too deep in the corner and I couldn’t get it stopped. So race day, if you look at the footage on race day, I am left wheels, right wheels right on the inside of the road, apex right there, trying to set the nose of the car. There would be times where I would throw my whole body back because I think, “Ah, the front end’s gonna touch (the slippery stuff) when I rotate around the corner,” but it didn’t. It was all good.

Excellence: There can’t be anything that exceeds this year’s victory itself, but there’s gotta be one or two quieter memories that are special to you.
Zwart: Well, one was that I hadn’t raced at Pikes Peak for over five years and the welcome back I got from everybody across the board – the competitors, the fans, and everything – it was really nice. It was quite charming. It was just nice to have everybody kind of welcome me back. It was funny because more than one person told me they would miss the rivalry between me and Rhys Millen. One guy came up to me, “You know what I’m gonna miss this year?” I said “What?” “The Rhys Millen and you rivalry.” I said, “Oh believe me, there’s still a rivalry. Rhys wonders every day if I’m gonna break his record.” It was all still there.

Certainly, within the run, just the speed I would carry in the runs would just be phenomenal. Not that I’m paying a lot of attention to it. You know, I only pay attention in there to the sound of the car and to the shift lights. And when I would see the shift lights go on 50 yards earlier than where I’d seen them the last time, that’s pretty satisfying, and you just knew you were doing well.

When I got to the top, I knew I’d only made one mistake going up… I thought, all we want to do is break Rhys’s record, which is a 12:09. And if we were in the elevens it was gonna be a real good thing. I mean, the whole team and everybody had such support for me and we’d kinda made some goals and things, but to be in the elevens was gonna be great. And I got to the top, and when you get to the top at 14,000 feet, 156 turns, you’re quite winded. The air is really thin and all that stuff, and when you put it on the edge over and over again, especially that last section where there’s large drop-offs and everything, and you kinda even have to tip-toe around some things – and tip-toe is a pretty minor word when you consider you’re tip-toeing at 80 miles an hour – but when you look at all those things when you get to the top, I really sat in the car for a while and I thought, that was it.

You know, I could go back and drive again and go a little faster, but as I lay it on the line, the first time you see the course that day, that was it, man – I hope I did it. That was all. I hope I did it. And when the time came in, I was just elated.

Also, this was a year that was different. I had Porsche Motorsport North America support there with the president, with Paul Ritchie, with Andrew Gregory and James was there. I had a fantastic crew chief in Dennis who had run the car in the Patron Cup. He’s a big rally fan.

Excellence: Did you see them at the top?
Zwart: No, they wait at the bottom.

Excellence: And how long before you got to see them?
Zwart: Well, about three hours. But I did a big radio interview, so everybody knew how I was feeling and all that stuff. It’s a very solitary thing up there. And you know, Rhys wasn’t up there yet, and a lot of the guys are kinda having their own success or failure up there as it is. So I did the radio interview, and I gotta say I was just so elated. I don’t recall ever feeling so good. Pirelli was there, and their guys were there. I just felt that, (with) so many people that were physically in charge of things on the car, (I couldn’t) let anybody down. To have the results we had was just an extra-sweet feeling. Normally I run with a crew that’s a group of guys from up there, and it’s kinda no big deal. So this year it felt like a big deal and we had the results we did. It was really, really satisfying.

Excellence: So what’s for next year?
Zwart: You know, when you run one race a year, I think you’re kinda glad to get it done. I’d love to do something else, but to me, (Pikes Peak’s) losing dirt every year is a little bit disappointing ’cause I love sliding so much. But we’ll have to see.

The goal this year was, through my car and through this event, to establish a baseline so that we understand a package that will work well at Pikes Peak, and that package involved the engine management, the suspension, the transmission, and the tire package. And so, those things and what we discovered there will be adaptable on any 997 GT3 Cup. And so the goal out of this is to create a GT3 Cup class (at Pikes Peak).

As to what involvement I’ll have if there is a Cup car class and whether I’ll compete in it or whether I’ll just oversee it, or what I’ll do next year, I don’t know what I’ll do. But certainly Motorsport put in the effort to make sure I had the best of the best there. We discovered everything that worked, and nothing that really didn’t work, so I feel confident that any guy can go there. It’s a fantastic car to drive.

Excellence: In many ways, this win was more interesting than anything we’ve seen from a GT3 Cup thus far…
Zwart: Look at Porsche’s history. It had such a great hillclimb history in its beginnings and people ran them every weekend in Austria and Switzerland and Germany. So (there’s) that whole history there, and you think it’s coming back with what I proved to be an extremely versatile car this year. If there’s a Cup car class and 10 or 20 of these cars, all kind of to a spec, it would be a great race. And there wasn’t a run I’d made where the fans didn’t come up and say how fantastic the car sounded. The car has an entirely different sound from anything else – it’s crisp, it sounds beautiful, and you know, I’ve run turbo cars there that near the top I’ve been waiting on power. Never in the GT3 Cup. It’s exciting clear to the top.

Excellence: How much support did Porsche Motorsport in Germany lend to this thing?
Zwart: We talked to Roland Kussmaul at Laguna Seca and he had some suggestions for suspension and a few things. We applied those things to the car — so we had Roland’s influence. But we had PMNA build the car; Jim did the suspension set up based on what I kinda thought I wanted. It was truly a North America-prepped car. And that’s something pretty rare for them, to put a full car out there.

Excellence: So it’s a keeper then, eh?
Zwart: You know I never keep my Pikes Peak cars.

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