Well I think the debate is more on the lines of what mods detract from a vehicles values and what mods enhance (or at least make no difference) to the value and what mods can be considered just plain desirable.
The absolute purist collectors market is very small I believe, as are the numbers of absolutley stock Zs out there. I suspect the majority of purchasers these days are buying the cars because of their looks, classic status and their degree of performance.
However certain areas of the cars can be improved on, I believe in a way that won't detract from their value. Most cars are going to need new shock inserts, so why buy old technology when new technology is available? The stock brakes were adequate (just) in the 70s, can they really be described as adequate for today's traffic conditions? What constitutes a mod there? Does putting improved performance pads on stock disks ruin a car? Does putting slightly larger disks and calipers on from other cars of the Z period detract even though they make the car safer?
So how far on the scale of modding can really be considered detrimental to the value?
On the other hand highly modded cars can be sold but like the totally original examples are only desired by a smaller market. Let's take Mark Rayner's twin turbo beasty as an example. It's one of the more extreme raod cars in the country but you could hardly say it isn't worth as much as a stock example! I bet the majority of members in the club wouldn't object if Mark's car happened to be in their garage
Ah, don't you just love an early Sunday morning debate?
Cheers,
Rob