The Cobra sits quietly, its new steering muscles rippling under the skin...
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Once again we were fortunate to have beautiful weather, with sunny skies and temperatures peaking in the 80's both days. Some clouds came through at one point and there were some light sprinkles, but they passed quickly and the track remained dry.
After the event, I stayed in western New York for a few days with my friend Steve Smith and his daughter Asia. We had a great time racing on the X-Box and some superb road courses (including a chicane-free Watkins Glen!) in Papyrus' NASCAR Racing 2003 Season on Steve's networked PC's.
It was extremely interesting to run the Glen in a simulated NASCAR stock car right after running there in the Cobra. I found that the things I'd learned in the Cobra applied directly to the sim, which has a very realistically modeled version of the Glen. Even though Steve has been running the sim stock cars for weeks, I was able to outrun him after relatively little practice.
Great stuff!
My big tweak for this event was power steering. According to Gary Cheney, all the top FFR Spec Racers are going with power steering so they can run more caster. This helps with the front tire contact patch, because with the FFR front suspension geometry it's difficult to get enough static camber to get even tire temperatures across the tread. Usually the outside edge runs hot, and this means less grip, understeer, and rapid wear on the outer edges of the tires.
The extra caster causes more dynamic camber gain when you turn the steering wheel, so the contact patch stays flatter and you use the tire more efficiently. This helps turn-in and makes you less prone to overpower the front tires (always a problem with my Cobra) by turning the steering wheel too much, thus taking the tires past their peak-grip slip angle.
This sounded great, and Gary was very quick at Mosport. He said he loved his new power steering, and his times supported the theory. Also Spec Miata racer Michael Carr independently used the same logic when explaining the setup on his Miata: he uses as much caster as possible to take advantage of the dynamic camber gain. Using dynamic camber rather than static camber also means the tires sit more square on the track in the straight-ahead position, which gives better braking.
This all sounded really convincing, so since I already had the power steering rack from our original donor car, I decided to tear into the job in the two weeks between Mosport and Watkins Glen. I figured it shouldn't be too expensive, since a used power steering pump would be $30 and all I'd need would be some hoses and a new belt, plus an adjustable bypass valve made by Heidts, which would allow me to dial in the amount of boost provided by the power steering. I could also copy the excellent installation done by Stevie Knowlton in Gary's car.
Well, it turned out to be a bigger job than I expected, and much more costly as well. The Heidts valve was almost $100 including shipping, a Ford Motorsports A/C eliminator bracket was over $40 from Forte's, a new Mustang power steering hose was $40 from NAPA, additional custom hoses and hardware were $60 (thanks to Paul at Big Al's in Rye for the custom work!), the belts (I wound up using two) were almost $30 each, a second used power steering pump (this one with the necessary bracket) was $50, and an alignment was $80 (thanks, Paul at Sullivan Tire!)
Trips to Portland, Candia, Chester and various local hardware and auto parts stores ate up a lot of time, as did the removal of the emissions pump and plumbing. Getting the manual rack out and the new rack in was a bit of a pain, since there was very little clearance between the frame and the radiator fan shroud.
Also I had to make a couple of trips to the hardware store for taps to clean out threads in the heads, first to plug the holes left by the removal of the air pump's crossover pipe, and then for the Ford Motorsports bracket. Finding the right length belt also took a couple of trips.
Still, the whole job went pretty smoothly, and fortunately nothing leaked once I had it all together.
Unfortunately, when I first tried the power steering on the street, I hated it.
My old Flaming River manual rack had a slower ratio, and marvelous feel. Its beautifully smooth and precise steering - especially on turn-in - was one of the more delightful aspects of driving the Cobra, but now all that was gone, with a sticky, over-damped feel on-center, and an ultra-light, overly twitchy response off center.
I found it very difficult to get a smooth, precise turn-in, especially on fast corners. Instead, I tended to turn in too much and too fast, and have to unwind, resulting in upleasant little wiggly motions which would obviously not provide optimal lap times on the track.
To my dismay, during the alignment, I discovered that the same spring to A-arm interference problem that was preventing me from getting more static camber also prevented me from dialing in the amount of caster Gary was using. Without proper caster, the steering lacked adequate self-centering effect, causing too little feel and steering that was way too light.
I cranked out the Heidts valve to increase the weight of the steering, but unfortunately this had almost no effect on the effort and feel in the turn-in phase; it only made the steering heavier later in the corner, which is when I really needed the boost.
After several phone calls to various people I decided to crank the Heidts valve back in to Gary's setting (four threads showing) and go with an underdrive pulley set to reduce the output of the power steering pump. This would supposedly help by increasing the steering effort a little.
The pulley set was another $80 and a couple more local trips - on the day I had been planning to just load up the trailer and van - but it did seem to help somewhat. Or maybe I was just getting used to the faster ratio and lighter effort. At least now the darn car was easier to park!
A weekend of street driving and a tweak to the steering shaft mountings freed up the on-center feel, which also helped, but I was now up to over $500 for the job - a significant chunk of my budget for the year.
I sure hoped it would prove to be worthwhile!
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We got to the track in time to unload and set up in a garage at the track. I have to admit that I still find it awesome to be encamped in the exact same garage where I watched Team Lotus work on those gorgeous Lotus 72's back in the early 70's!
Again John, Nate, and others were very helpful in assisting me withe more physical work, especially unloading. Thanks, guys!
I was very grateful to have my van and trailer, which allowed me to bring all my tools and spare parts, all organized and tidy - and even my electric cooler. It took only a few minutes to transfer everything to the garage and wind up with a workshop that was nearly as complete and convenient as my workshop at home.
The only thing missing was compressed air for my air tools; for some reason the management at the Glen has disconnected all the air lines to the garages, even though they still have a compressor! Augh!
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Also the track itself is a bit intimidating; its relatively fast turns are mostly surrounded by guardrails, with little runoff in most corners, and there are a lot of places where a small mistake will let the guardrails eat your car.
Because of this, the Glen is, for me, a mental track. A big part of the learning curve each weekend is getting enough confidence in the car and in myself to really attack the corners, and this takes time. Last year I gained ten seconds on the second day!
However, last year my confidence had been dented by two spins at Summit Point a few weeks earlier. This year I'd had a couple of very good events, first at Loudon and then at Mosport. My confidence has been growing, and this is paying off.
One thing I'd learned last year did carry over: I was able to take turn 2 flat from the outset. By the end of the first day (Wednesday) it was easy flat. I'd gotten the line down, so my transition from turn 2 to turn 3 was smooth and scrubbed off the minimum of time.
This sequence is critical to lap times because taking these turns flat essentially turns the Esses into part of a very long straight that goes from turn 1 all the way to the entrance to the Inner Loop.
(The Inner Loop is now, by the way, universally referred to as the Bus Stop, probably because all the NASCAR guys have been watching Formula 1 on the Speed Channel and immediately noticed the similarity of this section to the Bus Stop chicane at Spa. Whatever. It's still a chicane, whatever you call it.)
John Spain made a very useful suggestion for turn 7: drive very far out to the left, putting your left wheels off the concrete patch and turn in very hard, just where the track is turning upward so you have lots of download and plenty of grip. Then apex early, about 10 feet earlier than the cone. This let me take the corner at full throttle all the way from turn-in to exit.
Nate made an excellent suggestion about turn 6: drive over a black patch near the entry with both wheels. This ensures you're on line past the apex and have enough room for tracking out without having to pinch the exit. Nate is also the person who taught me how to take turn 2 flat last year, so I owe you, Nate!
All these driving secrets allowed me to quickly get into the 2:21's (2:21.6 in the second session!) and I was in the 20's by the end of the day, with a 2:20.0 in the last session.
This lap came, incidentally, when I passed Nate in his new Miata. He said he did his best lap time on the same lap! Who says we're not competitive with each other?
My student this weekend was Rob McLennan, yet another FFR Spec Racer driver. Rob was smooth and consistent, and did a particularly good job under braking (I love it when I can learn from my students!)
Rob's car has 3:08 rear end gears, which is a little taller than my car's 3:27 but shorter than the Spec Racer-mandated 2:73's. It was interesting to see where Rob was able to shift; in some corners he might have had a slightly better gear than I do.
I still prefer my own 3:27 gears to anything else I've tried, though; it seems to have a correct gear for just about any corner (except turns 3-4 at Loudon). If I had a Tremec with a useable 5th gear, however, I'd definitely go for a shorter rear end ratio.
At Watkins Glen I was able to drive another Lotus Esprit. At Mosport I had driven Mike Fridmann's 300+ hp Turbo 4. At the Glen, Mike kindly arranged for me to drive Andrzej Brzezinski's Esprit Turbo V-8, which has something like 360 hp!
I drove the Cobra immediately after each Lotus, and found there was little to choose between the three cars in terms of handling. The Lotus' longer wheelbase made them a little more forgiving, and the V-8 was noticeably more powerful than the Cobra or the Turbo 4.
All three cars have superb handling. When I got into Mosport's turn 9 a little hot and got the Cobra a little sideways, it reacted exactly the same way as the Turbo 4 did in the same situation; a slight lift, a little opposite lock, and it hooked right up.
On the other hand, the Cobra cornered flatter and seemed to have more grip than the Turbo 4. I didn't have enough time in the V-8 to feel that I was really exploring its limits - but it felt like its limits would be extremely high!
I found the V-8 to be a little more comfortable to drive than either the Turbo 4 or the Cobra, but that comparison may have been colored by the fact that I wasn't as comfortable with the Cobra's new power steering at the Glen, and also by the fact that I probably wasn't really close to the limit in the V-8.
The Lotus Esprit is one of the best-handling and most balanced cars in the world, but I found the Cobra's balance and predictability were nearly as good. Overall the Cobra compares very favorably with the Esprits I drove. Given where the Cobra was when we started with it in 2000, it was really satisfying to realize how good it is now!
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On Wednesday I noticed Lou behind me a couple of times and I waved him by on the straight before the Bus Stop, but he didn't pass me. After a couple of laps, I decided that he must not have wanted to go past, so I just carried on.
Oops!
At the end of the day, chief instructor Chris Tier took me aside and said that Lou was a bit upset with me that I didn't let him by. I'd been assuming that since Lou had more power, he could easily blow by me at the end of the straight. But Chris said Lou had been breaking in a new engine, so he couldn't turn up the boost whenever he wanted to pass someone. Also I suspect perhaps the Cobra was getting through the Esses a bit quicker, which made it more difficult for Lou to get close enough to pass at the end of the straight.
Anyway, I felt terrible. I apologized to Lou and promised that any time he came up behind me I'd back off and let him by. The next morning, he did just that and I let him past going into the Bus Stop. He was really moving! By the entrance of turn 6, he had disappeared from view.
As I came past the apex of turn 6, I could see clouds of dust billowing up from the dirt on the outside of the exit. "Uh oh," I thought. The exit of turn 6 is not a good place to go off; you're hard on the throttle at about 90 mph, going downhill, and there's almost no run off area on either side.
I backed off immediately. As I went further around the corner, Lou's car came into view - bouncing off the tire wall on the left, in a cloud of tire smoke!
Fortunately, Lou was ok and so was his car. The front end looked bashed up, but Lou just removed the bumper and grille and carried on for the rest of the weekend.
It turned out that another car had overheated and dumped antifreeze on the track just before Lou got there. As a result, his car pushed wide and went off the outside on the right. When he got it back on the track, the wheels must have been turned too much, and the car just hooked left into the tire wall.
Lou tells me that the car is fine and he was able to just bolt everything back on.
This is the second time I've been the second car to arrive at the scene of a fluid dump, and the car ahead of me wound up in the tire wall. I'm very fortunate it wasn't me that discovered the fluid! Somehow I don't think that fixing the Cobra after a tire wall encounter would be quite as easy or inexpensive as it was to fix Lou's Omni.
Nate also had a traumatic moment. His student, driving a brand new Subraru WRX STi, went wide at the exit of turn 7, got sideways, and spun into the barrier on the inside. The airbags deployed, so Nate and his student got a ride back to the pits in the ambulance. Fortunately both of them were ok, and the Subaru, somewhat worse for the wear, was actually driven home!
On Thursday morning I put my brand new Kumhos on the left side and went quicker than I had on Wednesday, with a 1:19.2 in the first session in the morning. Then I got one of the club's fastest hotshoes, Chris Connacher, to ride with me for a few laps. It was a bit strange to be getting instruction right after giving instruction to my own student myself, but it was very useful!
Chris encouraged me to use all of the track, especially on the exits of 7 and 8, and to quit coasting for a half second or so between full throttle and getting on the brakes and to brake more aggressively, since I wasn't using the car's full braking force in some areas.
I can understand now why even top athletes have coaches. These are things that I know very well, yet I had allowed bad habits to creep in over time and wasn't even aware of them. I was being unconcously conservative to reduce the risk of crashing the car. Chris's reminders got me concious of these bad habits, and I was able to modify my behavior and cut them out.
The time with Chris, the suggestions from Nate and John, and the tweaks to the car paid off. I did a 1:18.9 in the time trial, which beat my best time from last year by a second. It gave me 2nd place in my class, SPA.
The only car in my class that beat me was Chuck Wasserot's 400+ hp T-1 Corvette, which I knew I couldn't expect to outrun. He wound up as the fastest car of the day, with a 2:12.
More importantly, I beat Gregg Metzger, the guy with the Mustang, with whom I was tied for the championship lead, so now I'm leading!
At the end of the day, after the time trial, there was time for about 20 minutes of open practice. Since I was planning to stay with Steve Smith that night, I didn't have to drive home, and I figured I could afford to expend the energy needed to run in that session. My only reservation was the possibility of damaging the car, which, if I should do so, would have been foolish now that the timed event was over.
I'm really glad I decided to run! On my third flying lap, I lowered my time by another second, to 2:17.9.
On that lap, everything I'd learned through the two days came together, and my confidence went up another notch. Now more or less used to the power steering, I was carrying more speed into the corners and turning in more aggressively. I was getting on the power earlier, particularly in turn 11. The car seemed to lunge for the apexes, and swept through the exit phase with more speed than ever. This lap had that wonderful, almost musical rhythm that you sometimes get when you're driving a really good car at speed on a really nice track.
I know there was still more in the car. I still wasn't getting back on the power as early as I could have in turn 10, and I was still tentative in the entry phase of turn 5, but I felt like I was using more of the car there and everywhere. It felt fantastic, and it paid off!
That 2:17.9 was two seconds faster than I'd gone last year, and a second faster than Nate's best time in the car last year!
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This year I've been doing a little better; the fact that I was able to do the power steering mod between the Mosport and Watkins Glen events is evidence of that. However, at Mosport I found the second half of turns 1, 2, and 4 to be very challenging, because in each of these turns the car is heavily loaded with downforce due to the vertical radius at the bottom of a hill. It took a lot of my physical strength to keep the car turning.
Last year I had a similar problem in turns 1 and 2 at the Glen, as well as the entry of turn 7, and the same problem always arises in turn 6 at Loudon, which has high vertical loading. In corners like these there is always the question of whether I'm taking the car to its own limit because my own physical strength might not be enough to turn the wheel hard enough to make the corner.
That problem was gone at the Glen. Although I did tire quickly, physical strength was never a factor in how quickly I took a corner. Also I did not seem to become as exhausted through the course of the event; I still felt reasonably energetic at the end of the second day - though I did mostly nothing but sleep for a few days after I got to Steve's.
On the downside, I was still making some little wiggly motions on turn-in occasionally, and I miss the lack of feel. By the end of the event, I was able to feel a trace of understeer through the wheel in a couple of corners (notably 5 and 8, which have downhill entry phases which promote understeer). However, for the most part I had had to adapt to the loss of feel through the wheel by instead focusing on feedback through the seat of my pants, which sometimes isn't as immediate or precise as good feedback through the wheel.
However, adding more caster should increase the feel and also possibly make the front end even more efficient, so my next project is to rework the front end to allow more caster and camber adjustment.
A number of things have changed on the car since last year: stiffer rear anti-roll bar, improved Ackermann, more front camber, and the Kirkey seat. However, my improvement in lap time probably came at least partly from the power steering, because it made it easier for me to drive the car, and also because the additional caster meant that the car had virtually no understeer anywhere.
For what it's worth, none of the FFR Spec Racers - which have identical engine and drivetrain to mine, weigh the same and use the same tires - got anywhere close to my best lap. As far as I know the best Spec Racer time was Gary Cheney's 2:20, and none of the others got below 2:22.
Considering that their air dam and small windshield give them a downforce and drag advantage (perhaps offset to some degree by their taller gearing), I guess my suspension mods are working!