Good find! You obviously looked harder than me...
So it's multicore optimised from SP1 onwards? From what I read, quad core did not seem to be much help - users getting on better with dual core.
My general experience with graphic intensive games is that even when unoptimised, newer (ie faster) dual core will run better than single, even if only by a little.
Triumphs I have owned - Herald, Vitesse, 2000's, 2500, Stag. Is there any other make of car?