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David Beard's Somewhat Strangely Varied Website

Strangely Varied Seventies Suspension

Many people complain that F1 is not what it was, usually on the grounds that there is little overtaking. Perhaps, but on the racing front I think rose coloured specs are sometimes applied when recalling the standard of racing in the past. For me, the main thing that has been lost is visible technical diversity. In the 70s, there wasn't a lot of variation on the engine front (being the DFV era), but the progression of ideas in the area of chassis design was fascinating.

Taking front suspension design as an example:

In the sixties racing cars were of the cigar tube variety. To go along with this minimilisation of frontal area, most cars had inboard coil spring damper units operated by beefy rocker arms, doubling as the top suspension member. This is a typical arrangement, the Lotus 49, being the work of Colin Chapman and Maurice Philippe.
Not long into the 3 litre formula the cigar tube went out of fashion...a chubbier form became the vogue and straight forward double wishbone systems with outboard coil / damper units began to reappear. Despite his flirtation with the complexities of the Cosworth 4wd car, this system Robin Herd produced for the March 701 was about as basic as it gets. Len Terry's cigar tube BRMs (and his AAR Eagle too, for that matter) had the usual rocker arm operated springs, but when his replacement Tony Southgate penned the gorgeous pregnant goldfish forms of the P153 & P160, outboard springs reappeared here too.

The Lotus 72 was another Maurice Philippe creation under Chapman's direction. This front end really pushed the boat out. I've never been sure whether the 72 was a great success because of, or in spite of it, but red herring or not, much of the opposition rushed around trying to copy the driveshaft driven inboard brake system, if not the compact "there and back again" compound torsion bar springs.

Over at the timber yard Tyrrell designer Derek Gardner didn't jump to imitate the 72 straight away, however. In replacing the team's March 701 he took strong design cues from the Matra MS80 they had previously campaigned so successfully. Look at that bottom wishbone: solidly constructed out-houses spring to mind....

Robin Herd's second F1 March (the 711) was much more interesting and elegant than his first, but it was (necessarily?) corrupted as the season progressed. Whilst the Costin bodywork concept was being ruined, the inboard brakes were jettisoned leaving the this gaping hole where they should have been. The rocker arms operated the springs ahead of the tub in a position where they no longer had reason to be. The whole car became an example of abandoned logic. (Good job they had Ronnie.)

When Gardner decided to take notice of Lotus and go to inboard brakes with the Tyrrell 005 the look was more Tonka toy than 72, but JYS was probably happier with that.

This is the Iso Malboro Williams. I can't recall the type number or the designer's name...but look, another chassis with an unused gaping hole into which an inboard brake system could be fitted. They never did, though.
Ralph Bellamy designed a baffling linkage system to operate the inboard spring units on the pregnant goldfish McLaren M19, giving a rising rate effect. It was retained for the immediately effective Gordon Coppuck M23, and was never corrupted with attempts at 72 emulation. However, later iterations of the M23 reverted to a simple rocker arrangement, taking us back to the start of this little yarn.

Rocker arm suspension then remained with us into the ground effect era, but the requirement for ever stiffer spring rates and wider track meant that the rocker arms were having to resist enormous bending stresses. Hence pull rod and push rod systems appeared, with the latter, engineeringly less elegant solution eventually achieving dominance because of the better access to the spring unit on the top of the tub.

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In the sixties racing cars were of the cigar tube variety. To go along with this minimilisation of frontal area, most cars had inboard coil spring damper units operated by beefy rocker arms, doubling as the top suspension member. This is a typical arrangement, the Lotus 49, being the work of Colin Chapman and Maurice Philippe.	Not long into the 3 litre formula the cigar tube went out of fashion...a chubbier form became the vogue and straight forward double wishbone systems with outboard coil / damper units began to reappear. Despite his flirtation with the complexities of the Cosworth 4wd car, this system Robin Herd produced for the March 701 was about as basic as it gets.	Len Terry's cigar tube BRMs (and his AAR Eagle too, for that matter) had the usual rocker arm operated springs, but when his replacement Tony Southgate penned the gorgeous pregnant goldfish forms of the P153 & P160, outboard springs reappeared here too.

The Lotus 72 was another Maurice Philippe creation under Chapman's direction. This front end really pushed the boat out. I've never been sure whether the 72 was a great success because of, or in spite of it, but red herring or not, much of the opposition rushed around trying to copy the driveshaft driven inboard brake system, if not the compact "there and back again" compound torsion bar springs.	Over at the timber yard Tyrrell designer Derek Gardner didn't jump to imitate the 72 straight away, however. In replacing the team's March 701 he took strong design cues from the Matra MS80 they had previously campaigned so successfully. Look at that bottom wishbone: solidly constructed out-houses spring to mind....	Robin Herd's second F1 March (the 711) was much more interesting and elegant than his first, but it was (necessarily?) corrupted as the season progressed. Whilst the Costin bodywork concept was being ruined, the inboard brakes were jettisoned leaving the this gaping hole where they should have been. The rocker arms operated the springs ahead of the tub in a position where they no longer had reason to be. The whole car became an example of abandoned logic. (Good job they had Ronnie.)

When Gardner decided to take notice of Lotus and go to inboard brakes with the Tyrrell 005 the look was more Tonka toy than 72, but JYS was probably happier with that.	This is the Iso Malboro Williams. I can't recall the type number or the designer's name...but look, another chassis with an unused gaping hole into which an inboard brake system could be fitted. They never did, though.	Ralph Bellamy designed a baffling linkage system to operate the inboard spring units on the pregnant goldfish McLaren M19, giving a rising rate effect. It was retained for the immediately effective Gordon Coppuck M23, and was never corrupted with attempts at 72 emulation. However, later iterations of the M23 reverted to a simple rocker arrangement, taking us back to the start of this little yarn.