Hall/Redman Interview, Page 2
Page 1 of interview.
Page 3 of interview.
The Brian Redman International Challenge at Road America,
Jim Hall Grand Marshal.
The Chaparral display above with the sucker car
in the foreground.
I continued the conversation by asking about shock absorbers,
more correctly referred to as dampers.
PH: "At that same time what was going on with shocks?
Did you have much choice? Both Brian and Jim look at each other
JH: "We were running Konis too, I think. We tried some
Armstrongs I think. They had an adjustment on them. Compression
maybe?" He looked at Brian.
BR: "Yes, it was a compression adjustment. But people
didn't take much notice of shocks at that time."
JH: "Well, we were running on light enough springs and
small enough tires that there really wasn't much of a problem.
The cars were more like passenger cars than the racecars of today.
With those light spring rates the tires would ride over the bumps."
BR: "The tracks were much bumpier then. In those days
most of the tracks were very bumpy. Formula 1 cars and Indy cars
of today can't tolerate tracks that bumpy."
JH: "The tires stayed in contact with the gound most
of the time and it didn't take a whole lot of damping to do that.
We learned as the tires got stiffer that you had to back off
on the rebound forces to let the wheel come back down and make
sure the tire didn't jump up off the ground. But it depends on
tire stiffness. Damping is a little bit black art anyway. Today
it might not be but I'm talking about the 60s."
BR: "In 1969 on the Chevron cars we started using Bilsteins.
They worked a lot better."
PH: "That was a gas-pressure shock."
JH: "That made a lot of difference, the gas shock. Before
that the shocks used to overheat and they went away."
BR: "These days the teams have got guys who do nothing
but make shock changes."
JH: "Yeah, all they do is change little features in the
shocks all the time. Well, they've got good data. They go to
test rigs where they can bounce the wheels at all the different
frequencies. They can look at track data and tell what the hop
frequency is at each track. They can duplicate that at these
test rigs and start jiggling around with the shocks until you
get the thing damped out. It's kind of the same thing that's
happening with engines. It's not that everybody's so much smarter
than they used to be but they can measure everything and tell
what's doing on. They can fiddle with the fuel and spark and
make the engine better."
PH: "When you had that first car built by Troutman and
Barnes, what were the ideas you had built into that car that
made it different from the cars you'd been buying from manufacturers?"
JH: "I'll tell you where I was at that point. Hap Sharp
was a friend of mine and a customer, really. I sold him quite
a few cars. He always tried to get the latest cars and I was
similar. We worked a differenct path. He made his inroads at
Cooper and I did the same at Lotus. I could talk to Colin [Chapman]
and try to get the car that I wanted. Hap had the same relationship
with John Cooper. But we realized that when we went to the West
Coast races Jack Brabham and Sterling Moss would have later model
cars than the one we just bought. Not only could they drive better
but they had a better car.
"We figured this wasn't going to change and I thought
I might be able to do better. I think I talked to Troutman at
Riverside and he said they were going to build a car incorporating
all the things they learned at Scarab. They wanted to build a
lightweight, Chevy-powered racecar. I told them I was interested.
I visited them at their shop in Culver City. They had the car
layed out. They moved the weight back a long ways and it was
going to be a simple car, easy to maintain, lightweight, stop
good, with big tires.
"That sounded like a really good combination to me. We
were running against Climax-engined cars with 2.5 liter, four-cylinder
cars. And the price wasn't bad. I thought it was quite economical.
So I told them, if they needed something to get going, I'll buy
one. That's the way that happened. I got the first one and later
PH: "So it was already designed, the chassis and suspension
JH: "Yeah, I didn't hardly have anything to do with it.
I made some comments about a couple of things. But it was basically
PH: "As you started making the other cars and getting
some downforce on them, how did you maintain the balance of the
JH: "That's a development. If you look at the history
of the thing it's really quite simple. I had some experience
and I started doing some driving for Chevrolet. I drove the Corvair
for them. They had a lot of trouble with that car. They wanted
a guy that wouldn't turn it over. I drove the Corvair a lot.
I took expert witnesses for rides-maybe 25 of them-so they would
understand how the car worked.
"We'd drive around the skidpad and take air out of the
rear tires until the rim touched the ground. That was one of
the allegations in the lawsuits that, if you had low tire pressure,
it would flip. You cold flip it but you had to work at it."
PH: "That was the swing-axle car?"
JH: "Right, '63 and earlier."
PH: "Nobody wanted to notice that VW was selling a car
with the same suspension."
JH: "That's right. When Chevrolet designed that car they
said lets build a simple car. What's the model? Well if it works
for VW it should work for us. There were some problems with that
design but then they fixed it. That's where I got involved. They
looked at our car and said, 'Gee you don't have that trouble.
What are you doing?'
"Well we were doing it different with four-bar links
and rear weight bias same as the Corvair. That' s how my relationship
with Chevrolet started. I did a lot of driving and I got to instrument
the car. I knew what the car was doing. It wasn't just what I
thought, I knew. I knew."
PH: "That had to help, just driving the car and looking
at the data."
JH: "That's right. We compared the Corvair to Formula
Jr.s and to our car. You know a Formula Jr was really a high
cornering power car. It didn't have any power but it was a good
little race car. We compared all that stuff and that was really
beneficial to me.
"So when we first built the Chaparral II, I ran it for
a couple of months with no body on it, just the tub. We hadn't
built the body yet. We were still claying up the model.
"I was running the tub around to try to get some reliability
and find out if it would handle. When we put the body on it,
all of a sudden it slowed down. We thought, Gee it's supposed
to be faster with a body, slicker aerodynamically.
"Then we realized the front end had a lot of lift. At
120 mph you could move the steering wheel a little each way and
it would go straight on. So I did my first instrumentation myself.
"What I did was just wrap a piece of welding rod around
the A-arm, drilled a hole in the fender, marked it every half
inch, and counted marks as I drove the car. I'd run it down a
straight at 60, 80, 100 mph. So I had a curve, a lift curve.
I knew the spring rates so I knew the lift force.
"Then we put that snowplow on the front and I ran at Riverside
the first time. That was late '63. We took it to Nasau and Laguna
Seca. I had mechanicals at all three places. But it was quicker
by a lot than the other cars.
"That winter I ran it around the skidpad and it felt
good, it cornered good. It was nicely balanced. And I thought,
what you really want is a car that doesn't lift. You want it
to be as good at 100 mph as it is at 40. So kept screwing around
with it until I got it. I had the instrumentation, just the welding
"The other thing I had was a manometer with a bank of
about 20 tubes. I just tapped the body everywhere and I had a
polaroid camera mounted up front right near me with a cable release.
I'd go 100 mph and take a picture. So I knew the pressure distribution
and I started changing the body shape. I got it so it was a zero-lift
car at 100 mph.
"But it wasn't worth a damn because it oversteered. That's
when the light bulb went on. Right there! It was mid-winter 1963/64.
I thought, Jesus, if I can get rid of 300 pounds of lift on the
front, why don't I get it to push down. So we put the ducktail
on and we started to get 2 or 3 hundred pounds of downforce in
the back. Our lap times went down by 2 or 3 seconds. [Jim's leans
forward and his voice goes up a notch. He's as excited now as
if all this happened just last week.] In one week I dropped my
own lap time at Rattlesnake Raceway by 3 seconds. That's a pretty
The link to the third page is at the top.