Hey Gary,..I'm Not being 'Unsupportive of what James is trying to do',....
Heck, I have severe trouble with the flagrant re appropriation of the term 'Tectonic', by Modern Architecture,..so please, Pardon My comments re 'Spur',..but it Ain't in ANY Reference/Language dictionary I have looked at !!!,..
Actually,..Geoff,..the term 'Track', in Real Car terminology, refers to the Width of the Front and Rear Wheels, as measured to the 'Designed' Wheel Centreline, and is Not the 'Overall Width' as such.
I CAN Understand the 'Usage' of the term 'Spur, in relation to Delineating the Differences, as stated, between the Overall Width of the Body, compared to the Overall Wheel to Wheel Width !! It's just a Bad Word choice IMHO
Once again, the 'Pink Pig', is a Great 'Scale' Example, as although the Body, 'In Scale', would be Well over that of a Standard 917 'Porka', the actual Track Width Increase, was only a couple of inches, which was More to do with Airflow and aerodynamics, rather than an attempt to get a Wider Track.
Personally, I am somewhat surprised that the Matich SR3 is as Popular as it is, and can Only tend to agree, that it is Probably due to the available bodies being Completely 'Out of Scale' compared to the Real Car.
Having actually stood Very close to The Original SR3 & SR4's Waaay Back,..they were Both Very Small Cars, as compared to what was becoming the 'Norm' overseas in either Interserie or CanAm,..I would suggest that even though the McLaren M6 is also a relatively smallish CanAm Car, it Ain't No 'Petite' little Thing!
M6's and M8's etc are Damn Wide! M20's, have a Huge Plan Form, like a 917/30.
The Notorious and Oft' disliked (love it or Hate it) Autocoast Ti22 was one Damn Wide car, as was the Ferrari 612 and 712's and the March 707 another Super Wide beastie. Compared to say Lotus 30's and 40's, Lola T-70's, Chevron B-16's etc, they were Monsters,..a bit like Comparing Speedway Super Modified's with Sprint cars!!,..lol
I think trying to stick to True Scale Bodies, results in the 'Racers' eventually 'Navigating their way' towards the body that is Invariably the Widest and gives the greatest latitude in all it's other dimensions,.it's almost a No Brainer,... lol
This has even been 'Noted' as a 'Problem' within both the 1/32 Gt class and I would Imagine Group C as well, as in Both situations, there are Bodies that Are Quite a Bit Wider/Longer/Both!,..lol that from the choices, tend to 'Limit' a Racer's choice !!,..
Say No More,...lol
I can understand why the 'Handling' body dimensions 'Evolved' in the US Years ago, as it allowed the Many body Manufacturers around at the time, to all produce Bodies 'Representing' Many different current and Past Racing Cars and allowed one to make a 'Personal/Emotional choice, that would Not necessaarily place you at a disadvantage because of the Personal choice.
Mind you in some examples,..the 'Racers Creep' would definitely appear to have,..'Massaged' a few of the popular choices!!,..
I Can understand the Scale relevance with the 1/32 Modern GT and Group C,..etc, etc, especially when the Cars are Utilising 'Scale' sourced Bodies as such,..but with Lexan etc, it's a slightly Different world of realism realisation !!,...lol
Heck, even the Detail Lunatics from Germany aren't overly 'Anal' about the Exactness of the 'Scale' of the Car being represented in their series.
It has More to do with the Added Detail, Paint, Driver, Wheels etc, to Add to the 'Effective' Scale Appearance of the car,..I can 'Dig' it !!!,..ROFL
To Myself, 76mm seems somewhat 'Narrow' for a Few cars that Ran in that era. Is their a 'Cut off' as such as in the Year of When the Cars First Ran etc ??