Well I suppose Tony it all depends what people are happy with, not just what can be made to work.
I certainly would agree with you that I would not imagine Nissan would cast special increased thickness blocks for homologation purposes. However, we all know that manufacturers will seek cost reductions in light of experiences during production runs.
I have no empirical data, but very early blocks seem heavier, which could suggest greater thickness, or less tidy casting, though that does not necessarily mean they are 'stronger' per se'. Again of course they could have changed simply because the initial casting casts became worn, resulting in slight changes to the finished block. But I don't know what cast technology was used so its all presumptive.
The RRR I have is certainly 'different' to a standard block with an implication of increased strength, however that is circumstantial in the absence of empirical proof, which can be difficult to obtain without destructive testing. Having 'tried it', my honest opinion would be anyone looking at a new block would find an N1 more than adequate.
Now, with respect to liners. Of course you would expect best practice from an engineering perspective to be used. Does it work, clearly it has, do I like it? Not especially. Its position of last resort, especially on a high powered engine. But given the choice between no block and a lined one its a no brainer. In material terms, something designed around a cast iron block and associated parameters cannot be the same (as good?) when fitted with a *****. Does that mean it won't work? Of course not. However, it may well be good enough with respect to many applications and therefore deemed acceptable. Down to individual preference and available wallet!
With regard to GTST, I think as an example it demonstrates it can be made to work in an extreme environment, but we already know that from Darton's activities noting that they also add some cross strengthening too I believe. One consideration may be that the GTST doesn't exactly see a lot of road miles does it? Which is the environment most would anticipate to operate in and may present a different set of parameters.
In the end, if you chose to go with a ***** it may well be a sound engineered option but my point was it is not the same as the 'original' and nothing has been shown to demonstrate that it is better. The difference may not matter for you, in which case its the perfect choice. As I said, personally I would go N1.
DaveG
