Vintage Thing No.69 - Simplicity
I only know of Simplicity's legendary status thanks to Alan Staniforth's excellent Race and Rally Car Source Book, in which he gives examples of DIY racers. There are also details of some cars produced in factories but only by way of inspiration to the keen DIYer. There are several Austin 7 specials in this book that still fascinate me but Simplicity is the one that inspired and catalysed so much and so many that came later.
In his own words, Jack French wanted to "demonstrate that any effective and cheap formula racing car can be built by the enthusiast of limited means working in his garden shed."
At the end of the 1940s, the term DIY had yet to enter the public lexicon. Jack was one of many “IEs” - impecunious enthusiasts - and in the post-war years of austerity such enthusiasm sometimes appeared to defy rationality.
Simplicity did more with less but making it less took more effort than most people are willing to expend, especially if they are blazing a trail with every step.
Note the lightened from suspension with holes also drilled in the brake drums. That round thing on the side of the bonnet looks like it had a previous life in the kitchen. If it serves the right purpose why not? Not many pots or pans can claim to have had an active life in motorsport in their retirement.
The front axle is a Ballamy swing axle affair. Literally, the old axle was chopped in half and two mounting eyes were welded to the cut ends. These were then mounted in a bracket in the apex of the Austin 7's A-shaped chassis and the result gave an - at times - startlingly independent range of wheel movement.
Jack French shared his hard-won knowledge through the magazine of the 750 Club, the organisation behind racing Austin 7s. He spent some time "traipsing the streets of Birmingham" in search of a specialist who would stress relieve four con rods and a crankshaft by firing (gently) shot at them. Once he had found such an ally in his DIY activities, he told everyone about him.
Many of the techniques necessary for getting anything approaching high performance from an Austin seven engine sound quite bizarre to modern ears. For instance, the two bearing crankshaft was so whippy that it was necessary to reduce the height of the piston crowns in the two middle cylinders. At racing engine speeds, the crankshaft bends so much that the two middle pistons could hit the cylinder head without this precaution.
And the cylinder head was a very special one, made by Whatmough Hewitt in aluminium. Alan Staniforth converted some of Jack French’s contemporary costings into present-day buying power that precious head was the equivalent of two days work.
I have been under the spell of Austin seven specials for many years now and another book that I have enjoyed it is L M "Bill" Williams book on building Austin Seven Specials. This contains similar practical advice about tuning Austin Sevens and Bill Williams offers another demon tweak to allow the crankshaft bend safely. This involves radiusing the little ends of the conrods so that the Pistons can rock slightly and remain parallel in the bores of the cylinders.
He also advises not to have the crankshaft hardened. Presumably it needed to be sufficiently soft to bend and not break, and to bend and not break it needed to be structurally sound, which brings us back to Jack French's traipsings around Birmingham in search of a friendly shot-peener.
Jack French and Bill Williams both set great store in balancing and lightening the bottom end and stressed the importance of very careful assembly. Mind you, any tightness on rotation could be cured by a deft blow with a copper mallet - in the right place. Jack French even went to the extent of describing how to hand pick the best ball bearings for the main bearing ball races, again to counteract crankshaft whip in extremis.
Austin 7s after 1937 had a three bearing crank...
So after all that work what sort of performance could your average IE expect? Staniforth estimates output at the flywheel in Simplicity to have been around 35 bhp. That's 50 bhp per litre and two half times the factory output (14 bhp). Compression ratio was raised from 4.9:1 to match later production engines at 5.8:1. Capacity remained at 747cc with a 56 x 76mm bore and stroke.
Weight was around 6cwt which is 305kg. Converting bhp into metric gives 26kW and that gives a power to weight ratio similar to my old Dolomite Sprint! Deep joy - sounds like serious fun.
Bill Williams was an advocate of hydraulic brakes which were standard equipment on pre-war Morris cars of the same era, but Jack French was not. For Simplicity he chose to modify the existing cable brakes to ensure that the cable tension at each wheel balanced automatically and didn't have the car leaping to the kerb or towards the oncoming traffic. This was traditional Austin 7 foible. I think he was concerned about unsprung weight - the whole car doesn't weight much - but he also took the opportunity to engineer into this little doodad a certain amount of brake force distribution front to rear.
You don't get IEs anymore. We live - thank goodness - in a land of plenty these days but I can help thinking we've lost something since then. DIY is a synonym for a bodge, a word nowadays used to describe poor quality workmanship, when it really is the name for the art of making a perfectly serviceable chairs in the wings, because proper lengths of timber were obtainable.
An IE made up for his lack of pecuniousness (?) with boundless enthusiasm. Nowadays we have the wealth but not the time. Enthusiasm seems in short supply, too. I'm trying to suggest a modern day equivalent of Simplicity but can't. VSCC racers produce similar devices for events like Wiscombe Park but nothing truly contemporary suggests itself.
Jack French had to develop a car like Simplicity if he was ever going to go racing. He practised a kind of automotive alchemy on unlikely ingredients and was a kind of Engine Punk, spreading the word and lending out his car even if it represented the sum of much hard work and sometime scame home blown up. If ever that happened he'd put another racing engine together again in six days.
In his own words, Jack French wanted to "demonstrate that any effective and cheap formula racing car can be built by the enthusiast of limited means working in his garden shed."
At the end of the 1940s, the term DIY had yet to enter the public lexicon. Jack was one of many “IEs” - impecunious enthusiasts - and in the post-war years of austerity such enthusiasm sometimes appeared to defy rationality.
Simplicity did more with less but making it less took more effort than most people are willing to expend, especially if they are blazing a trail with every step.
The front axle is a Ballamy swing axle affair. Literally, the old axle was chopped in half and two mounting eyes were welded to the cut ends. These were then mounted in a bracket in the apex of the Austin 7's A-shaped chassis and the result gave an - at times - startlingly independent range of wheel movement.
Jack French shared his hard-won knowledge through the magazine of the 750 Club, the organisation behind racing Austin 7s. He spent some time "traipsing the streets of Birmingham" in search of a specialist who would stress relieve four con rods and a crankshaft by firing (gently) shot at them. Once he had found such an ally in his DIY activities, he told everyone about him.
Many of the techniques necessary for getting anything approaching high performance from an Austin seven engine sound quite bizarre to modern ears. For instance, the two bearing crankshaft was so whippy that it was necessary to reduce the height of the piston crowns in the two middle cylinders. At racing engine speeds, the crankshaft bends so much that the two middle pistons could hit the cylinder head without this precaution.
And the cylinder head was a very special one, made by Whatmough Hewitt in aluminium. Alan Staniforth converted some of Jack French’s contemporary costings into present-day buying power that precious head was the equivalent of two days work.
I have been under the spell of Austin seven specials for many years now and another book that I have enjoyed it is L M "Bill" Williams book on building Austin Seven Specials. This contains similar practical advice about tuning Austin Sevens and Bill Williams offers another demon tweak to allow the crankshaft bend safely. This involves radiusing the little ends of the conrods so that the Pistons can rock slightly and remain parallel in the bores of the cylinders.
Jack French and Bill Williams both set great store in balancing and lightening the bottom end and stressed the importance of very careful assembly. Mind you, any tightness on rotation could be cured by a deft blow with a copper mallet - in the right place. Jack French even went to the extent of describing how to hand pick the best ball bearings for the main bearing ball races, again to counteract crankshaft whip in extremis.
Austin 7s after 1937 had a three bearing crank...
So after all that work what sort of performance could your average IE expect? Staniforth estimates output at the flywheel in Simplicity to have been around 35 bhp. That's 50 bhp per litre and two half times the factory output (14 bhp). Compression ratio was raised from 4.9:1 to match later production engines at 5.8:1. Capacity remained at 747cc with a 56 x 76mm bore and stroke.
Weight was around 6cwt which is 305kg. Converting bhp into metric gives 26kW and that gives a power to weight ratio similar to my old Dolomite Sprint! Deep joy - sounds like serious fun.
Bill Williams was an advocate of hydraulic brakes which were standard equipment on pre-war Morris cars of the same era, but Jack French was not. For Simplicity he chose to modify the existing cable brakes to ensure that the cable tension at each wheel balanced automatically and didn't have the car leaping to the kerb or towards the oncoming traffic. This was traditional Austin 7 foible. I think he was concerned about unsprung weight - the whole car doesn't weight much - but he also took the opportunity to engineer into this little doodad a certain amount of brake force distribution front to rear.
You don't get IEs anymore. We live - thank goodness - in a land of plenty these days but I can help thinking we've lost something since then. DIY is a synonym for a bodge, a word nowadays used to describe poor quality workmanship, when it really is the name for the art of making a perfectly serviceable chairs in the wings, because proper lengths of timber were obtainable.
An IE made up for his lack of pecuniousness (?) with boundless enthusiasm. Nowadays we have the wealth but not the time. Enthusiasm seems in short supply, too. I'm trying to suggest a modern day equivalent of Simplicity but can't. VSCC racers produce similar devices for events like Wiscombe Park but nothing truly contemporary suggests itself.
Jack French had to develop a car like Simplicity if he was ever going to go racing. He practised a kind of automotive alchemy on unlikely ingredients and was a kind of Engine Punk, spreading the word and lending out his car even if it represented the sum of much hard work and sometime scame home blown up. If ever that happened he'd put another racing engine together again in six days.
Hi Bob just re read this and it is all so true, sad we don't have IE's now. Oh well back to the shed to do my bit.
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