Hi I am new to this forum - name "Roderick Rankin" . The Dynafour design was originally discussed at Ted Thompsons workshop in Kumeu and the rolling chassis and 2 Lawrence Power motors were built up by Curley in collaboration with Ted Thompson, this was the car that ran at the Aka Aka sprint. As I had been present at the early discussions about the construction of the car and had shown an interest in the Dynafour Ted Thompson told me about the car being for sale, I purchased the car from Curley as a rolling chassis with the motors out of the chassis. On getting the car home we found that the motors could not be easily put back into the chassis. So myself and my close friend "Colin Beanland" of Bruce McLaren fame cut the chassis off behind the seat bulkhead and rebuilt the rear chassis and modified the suspension at the same time. The motors were then installed. The name DYNAFOUR came from the fact that the Lawrence Power motors were aircraft standby generator motors, generators being DYNAMO'S and there was FOUR cylinders, hence DYNAFOUR. Each motor (approx 500cc each) was a twin opposed air cooled motor, magnesium construction, overhead valve with twin spark plugs per cylinder, magneto ignition, dry sump with crank, big end, little end. rocker gear all running on needle bearings. The motors were coupled together, the rotation of one motor being reversed so that a chain drive sprocket was fixed to the centre coupling, this drive then went to an Albion motor cycle gear box (a weak link) from here the chain drive was to a sprocket on a fixed drive swing axle rear suspension. A lot of the running gear was Renault. The rack and pinion steering being centralized by using two small sprockets and a coupling chain. The timing and ignition system had been reconfigured by Ted Thompson so that one magneto fired a spark plug in each cylinder of the motor it was driven by and a spark plug in each cylinder of the other motor, the same happened withe the other motor/magneto. Each cylinder was fed by an Amal Carb, a challenge to tune. the motors in this configuration would rev to 16,000RPM. Quite a scream. The body was built one saturday when Colin and I took the car plus a sheet of aluminum to a friend of ours Ivan Cranch. Ivan cut the ally by eye and then we were on the end of a wheeling machine with the body ready to trim out by mid afternoon. The wrap around windscreen was formed by cutting a cardboard pattern then perspex, placing my parents CONRAY electric heater on its back in the garage and slowly heating the perspex while rocking it backwards and forwards until the correct curve was achieved, amazingly no distortion. The photos of the hill climbs were with myself driving and were both in the Pukekohe area of South Auckland. First Grand Prix at Pukekohe was cut short as going around the loop at the stables (old circuit) one motor starved of oil due to no baffle in the oil tank, at the revs being pulled there was a large bang with a con rod exiting the side of the crank case. The pieces of the crank case were welded into place by Jim Mcoslum in Newmarket (don't think I have spelt Jim's name correctly) with the other spares I had the motor was rebuilt and I drove the car at a number of club meetings painted Blue. The gear box was always a problem in selecting the correct gear but we had tuned the suspension so that the car had led well even to the stage of passing Jim Boyd in the Cooper Bristol coming over Rothmans at Pukekohe. The car was then sold on to my friend Garth Taylor ( the photo in the Vercoe book is myself driving not Garth). If anyone has any idea as to were the DYNAFOUR ended up or is I would be very interested to know. Rod Rankin. (not Robert )
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Originally Posted by Oldfart
