As I was riding to work I thought again about this thread and in particular this post and it deserves are reply.
First or all 81Sprint, we are discussing Alfa Romeos, from a performance or handling point of view their weaknesses are SMALL. Yes the 105 series rear roll centre is too high but compared to 95% of other 60's and 70's cars their handling capabilities are very good.
Remember my car is 100% a road car and I am sure that I will be able to push the car hard enough to cause that required grin ... without having to lower the rear roll centre, or even change spring rates.
Thus again we are talking about modifying cars that other than build quality are miles better than other cars of their period. Ofcourse modern cars are better ... but as I've said before (if not in this thread, others) the more you modify a car the more it becomes like a newer car and similar. I go out of my way not to drive newish cars because I like to stay awake behind the wheel ... although lately I have not been sleeping well so hmmm maybe I should rethink that

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Did you really go out of your way to purchase a interesting Alfa Romeo to modify it so that it drives like every other boring newish car? Quirks are what make mechanical items interesting ...

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And again their isn't many in the motor/gearbox or handling department anyway!, they are good performers straight out of the factory.
Pete