Ferret Chassis

G Modified (1962-1963),
H Modified (1959-1961)

Introduction

Engine: The "powerhead" from a 3 cylinder 75 hp McCulloch outboard motor

Builder: Peter Dawson and many Chrysler engineer friends

Current Owner: Ed Valpey, of Gilford, NH

Ed is trying to gather more information and photos on this car.

Contact Ed via his email address.

Design & Development

The designer, Peter Dawson, reports that the car shown here "is the second Ferret built. The first was a front engine, rear drive car. [This] second car is much more sophisticated and incorporated many of the ideas I brought home from working with Colin Chatman at Lotus in England. At work back in the USA at Chrysler Engineering I had many engineering friends who contributed a great deal to the design and manufacture of the car. Work on the car started in late 1958 or early 1959."

"The major problem in building an ultra-light car is the development. We experienced many failures and made many changes as the car progressed. Specifically:

1. The front lower control arms failed due to an incorrect calculation on the braking forces involved. We replaced the lower A arms.
2. The vibration of the 3 cylinder engine was too great and broke the frame. We inverted the engine [to allow room] and added a harmonic balancer. [Ed Valpey says, 'The motor was mounted rigidly to the frame, so it likely broke in that area. I'm not certain, but I believe they had to invert the motor in order to accommodate the harmonic balancers that they made. The motor that came with the car doesn't have the balancers, and I don't know whether they were removed or the engine was replaced.']
3. The spool (locked differential) made cornering difficult. We replaced it with a Fiat differential.
4. The original single rear brake was replaced with dual rear brakes.
5. The original wheels were heavy steel. These were replaced by Magnesium wheels we designed and cast. The front wheels incorporated bearing carriers, ala Lotus wobble wheel design, which was copied from Aircraft design by Chapman. [Ed Valpey says, 'The front wheels carried the outer bearing race, and the centers were cut out and remain on the car today as "hubs". Unfortunately, the Magnesium wheels are not with the car today'].
6. The original Allison transmission failed and was replaced with a heavy duty unit."

Ed Valpey reports that, "The frame is made from 0.50" and 0.75" square tubing, and is very, very light. I haven't weighed just the frame, but I would guess it's under 100 lbs."

"Peter told me that they chose the engine because, at that time, it produced the greatest power to weight of anything commercially available ... more than 1 bhp/lb."

Further Comments

Peter Dawson further shares that, "I once calculated it takes about 1300 hours to build a car of this type, a little over a year, using every night and weekend."

"All in all, it was an exciting and labor intensive experience."

After racing the Ferret, "I next drove a  Lola 1100 and then built our last car. It was a  Hemi 426 powered rear engine Can-Am car with an automatic (1 speed) transmission. I finally finished up driving a Lotus Formula Ford."

Ed Valpey says, "Chris Kennedy was another Chrysler engineer who did much of the design work on the Ferret. He apparently made it quite high in the Chrysler engineering ranks and was very much involved in that company's drag racing success of the 60's and 70's with Hemi-powered cars. He is now retired in Maine."

Derek Harling recalls, "I worked for Chris Kennedy during my early days at Chrysler - around 1961. He was Manager (or was it Chief Engineer) of Advance Product Development and quite interested in "sporty car" racing - which was quite unusual in those days. I well remember Pete's project and visited his workshop quite frequently during the winter of 61/62. My clear recollection is that he was building the Ferret at that time - which is sort of borne out by the pics you have posted dated Aug 1961. But that doesn't quite fit with the comment about it being built in 1958/59. Maybe 1961 was just a major rebuild."

"Interesting to note from the pictures just how long the control arms were, front and rear. Pretty advanced thinking for those days. Also, look at the angle of the steering arms and tie-rods - those would give Allan Staniforth sleepless nights. Trying to eyeball some steering angles it seems like it had oodles of Ackerman - something like 500%?"