I don't normally post around here, but I think I should give you the insight of a "stranger".
Here in Portugal, the main attraction on the race tracks is the Historic Championship, for H76 cars and the like (the H65 are a minority around here). Cars like Ford Escorts BDA and Chevrons dominate the races (in their classes, that is).
There has been a long discussion about how legitimate and original are the Historic cars nowadays. For example, there are 3 (yes, three) Ford Escort BDA highly prepared (costs are around £100K or more
), with engines on the 280 bhp bracket and that can only run for 5 hours before a freshly rebuilt (a £8K job, I think, in England). And yes, these 3 Escorts are so much better than the original ones (even the 1975 Zakspeed examples). Yet, they are "original". And they clearly dominate the Porsche RSRs around here (something that didn't happen on the good ol' days).
What I'm trying to say is, how "original" are the current cars (not the "replicas") racing in Historics? Replicas can be better than an original car, but that's supposing that the original car has not been enhanced what-so-ever? Do you believe that? Does an original car race with the "original" parts? I'd think the answer is no. In that way, an original car has loads of "replica" parts, so, in essence, it's also a "replica".
More food for thught......
PS: I'm not trying say that historic races and their competitors because, they're so much better looking (and make better noises) than the stupid boxxy saloons that race nowadays in BTCC, WTCC and the like