I've a Bugeye and have had a bunch of them over the years. I don't find them that much of a handful. One can get a Sprite to oversteer, but what I'd call roll oversteer was typified by the Spitfire with its swing axles. The Spit was famous for this. Sure you're not thinking of a Spitfire?
Peter
It was a very common low-buck racer when I was involved ('67 - '72), and the consensus was that you gritted your teeth and opened your eyes a little wider in a Bugeye when you got up around 100...much like racing a Porsche Speedster.
Roll oversteer occurs when you're in a turn and the outside rear wheel moves backward, or the inside rear wheel moves forward, effectively steering the back of the car to the outside of the turn. It's most common on cars with solid axles and quarter-elliptic springs, such as Bugeye Sprites. They went to semi-elliptics in later models because the cars were so squirrelly at high speeds.
That's a different kind of oversteer. Porsche 356s, VW bugs, early Corvairs, and swing-axle Spitfires all did about the same thing, for the same reason.
With stock suspension, all of them tucked their rear wheels under in a turn when you got above a certain threshhold of cornering speed. The outside wheel would climb up on the sidewall and you'd go into drastic oversteer, usually spinning out.
There were several fixes for it, and you had to use one of them to race most of those cars. Decambering the rear end with shorter springs was one. Using a stiff anti-roll bar would cure the tuck, but it would introduce an oversteer problem of its own. There also was a strange sort of anti-roll bar called a "Z-bar" that was used some on Formula Vs. I think it had a short-lived popularity, but maybe they're still around.
The first car I raced was a John Fitch Corvair GT. It was a swing-axle car ('63) and it had the Fitch rear-suspension treatment, which was 2 deg. of negative camber and adjustable Koni shocks. It worked pretty well but it produced a strange phenomenon: when you started to turn right, the car would make a slight dart to the left, and vice versa. It felt a little like steering a motorcycle by steering slightly away from the turn to start your entry.
Anyway, it prevented the tuck, and with radial tires, it made handling fairly predictable. After a year of driving that I took a Porsche Speedster around the track and I felt right at home.
BTW, old Spitfires usually were given a *lot* of negative camber, 2-1/2 degrees or so, for road racing.
-- Ed Huntress
If you were lucky. I never raced, but for some years I was the guy in white coveralls hiding behind a haybale on the corner with a fire extinguisher ready to hand.
One Volkswagen I saw flip in a hairpin turn went completely over after jacking its left rear wheel. There wasn't a mark on it save for the right side fenders, which as near as we could figure was the first thing to hit the ground.
Feeling the rear end jack up on you, in a swing-axle car, is one of the most sickening feelings I can recall driving a car, short of staring at a car you know you're going to hit and seeing everything go into slow-motion. d8-)
-- Ed Huntress
I raced from '78 to '88, but never a Sprite so I can't say I have any experience in one at 100MPH. I do have plenty of experience with them sideways at lower speeds and never found them particularly demanding.
What class and region did you race in? I did ITB and GTA in the San Francisco region. Along with karts and autocross too. I was busy there for a couple of years...
Peter
Yeah, that sounds pretty busy. I raced for a time in FP and GP, North Jersey Region. I also raced in Michigan for a few months. I thought it was called Central Michigan but I see now that it's Western Michigan. Maybe they re-aligned the region in the last 35 years.
In '83 I went back to driver's school in an ITC car, but the medical examiner wouldn't let me race. That's why I quit in '73. Actually, they wouldn't renew my license.
-- Ed Huntress
Have you ever looked at a "Bird cage Masaratti" ? Back in about 1959 or so I saw my first one and thought how neet. ...lew...
I have two other books on racing and sports car design that also make interesting reading.
Racing car design and development by Len Terry & Alan Baker ISBN 0-8376-0080-4
The sports car it's design and performance by Colin Campbell ISBN 0-8376-0158-4
regards,
John
This is the space frame car I want to build.
Ed, I guess I got into this thread a bit late. I was about to recommend Mike Costin's book (I also have a 1965 or thereabouts copy), and was going to comment on the "birdcage" Maserati too. You beat me to both. We must share the same passion. I used to have a piece of Maserati type 61 bell housing that landed at my feet when a driver at the Cumberland MD races blew up his clutch halfway down the straight. Ah, those were the days.
When I lived in the UK, I visited the shop of a guy who builds Morgan
3-wheelers virtually from scratch. (OK, nothing to do with space frames, but a really cool cul de sac in automotive history.) If you can find a hulk chassis, he'll build you a car. He was even casting gearboxes for some models.-- Bob (Chief Pilot, White Knuckle Airways)
They sure were. I miss that racing. I was talking to my old boss earlier this week, an Italian and a big F1 fan, and he asked me why I don't care about F1 anymore. I couldn't answer him except to say that the technology has gotten so good, and it so permeates the sport, that I wonder what it is I'm watching when I see a race. I don't know who is driving whom.
He told me that Nicki Lauda got into a F1 car recently and drove it around the track, after having been out of the sport for a while, and he said "a trained monkey could drive this."
Maybe that's it.
Neat old...er, vehicles. I liked the ones with the J.A.P. or Matchless V-twins hanging out front.
-- Ed Huntress
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