The previous example I gave of the first Mustang GT350 - which was an actual race car made legal for the road in most US states - took things about as far as they could go, because it was a caged-up, noisy, uncomfortable beast with heavy controls (even by 1960s standards) which enough customers complained about that Shelby subsequently just made road cars that looked like race cars, with stripes, fake vents and so on.

The thing about homologation though, is its primary intention is to place limits on what could be raced. The consequence of producing some factory hot rods is incidental, and even then the manufacturer also has to sell them to at least recoup most of the cost.

Touring cars have been run under various rules over the years (around the world), from completely stock production in the 1960s to the various spaceframed silhouettes we get today (and have seen some categories use at least as far back as the 1970s). If you're going to use the road car homologation argument though, we're looking at stock production, Group A, and not many others.

Aussie classics like the Falcon GTHO, Charger R/T E49, the Monaro GTS and a number of others, are early examples of limited-run specials that were raced in very close-to-production specifications. Many 1960s Bathurst 500 (mile) race cars were even driven to the track to run them in, and sold as repainted used cars afterwards (sometimes discovered decades later). Sure, they were fun and exciting, but were they better?

Have you ever driven with a locking differential for example? They're clunky brutes, and the Detroit Locker in 1960s Fords required patience to engage as well, otherwise the driver spun the inside rear to literal destruction before they were due a pit stop, causing some crashes and retirements.

Race tracks with long straights also favoured thirsty big-engines, which turned out to be far from what was needed with a looming oil crisis. They're still a bad idea now.

Moving onto Group A in the '80s and '90s, again the rules required a minimum build quantity, but that didn't make them better road cars. Better performance cars, sure, but like the Mustang GT350 there were compromises that not even enthusiasts wanted to live with. Group A race cars used the road car shell and several major components, but also changed lots of things like the wheels, tyres, brakes, gearbox, seat, steering wheel and more. Even so, the things they needed to keep the same as the road car made for, well, worse road cars. Volvo for example, built the required 500 Evolutions of the Group A 240 Turbo, but since so few people would buy them (or maybe Volvo didn't want them on the road), they were de-specced down to normal versions for customers. As such, Volvo appeared to be caught out when they couldn't show that the minimum number of production cars in the right spec still existed.

As a milder and local example, low front spoilers are enough of an inconvenience that the VL SS Group A Walkinshaw was most often delivered with its front lip in the boot.

Ford's Group A Escort for rally in the 1990s met its homologation needs with a big turbo on the first 5000, then the remainder were given a smaller, more sensibly-sized unit to reduce lag and improve throttle response.

Then there's the one known as Godzilla. Sure, they made almost 44,000 R32 GT-Rs, and they were very advanced for their time, but many of their features like 4-wheel steering didn't catch on (that seems to have been a fad that died in the '90s, and it was disabled on the race cars anyway), nor did they even slightly resemble the Australianised earlier model that Nissan Australia continued bolting together here until they closed their manufacturing operations in Victoria in 1992.

The race cars were also re-engineered and "Australianised" by Gibson Motorsport, with many different components that did not come from (nor would they fit on) the road cars. This was impressive and probably made them quicker than their Japanese counterparts, but it did not affect the road cars.