Had some of my Cupra's for over 5 years, drove them hard and they ran sweet, no engine probs, maybe that's why SEAT don't say MUST RUN ON 98 on the fuel flap or in the manual, and as they build them I think they know what they are talking about.
Some people can take hard drugs for 5 years with no immediately noticeable problems either, and your point is ?
I certainly wouldn't want drive a new cupra hard over five years on only 95 octane, but that's just my own personal opinion
That aside did you even read what I originally wrote?. I wasn't saying people should use this octane or that octane. I wasn't saying your engine is going to suddenly blow up or your going to suddenly have issue with it, far from it, I was just explaining in simple terms ( there's a far better technical explanation available in the technical documents than I could ever write ) what the car, or more importantly what the cars ecu/dme etc does to compensate if you put a lower octane fuel in your modern high performance car.
Now im sure Seat do know what they are talking about (although judging by how busy the forum is & if you read many of the threads on here, I'm sure many people probably wonder if Seat actually do know what there talking about ) ,and im certainly no expert on the minuet details of bosch engine management system or other similar systems, and don't take this the wrong way, but I'm guessing your not either, as you seemed to think you would hear this knocking I spoke of, much like you might hear a carpenter banging in large nails with a bloody big hammer, and your only reply to my comments was to say it's rubbish and you've never ever heard your car engine knocking, so you clearly don't understand it at even a basic level.
Anyway don't take my word for it, all the information about these things are out there, you even used to be able to download it as a collection of pdf technical manuals from bosch, and to be frank they know far more about it than I do, or you do, and I hazard a guess, that they probably know more than Seat, which is why you see bosch engine management systems or similar in many brands of car the world over, and why you don't see Seat branded engine management systems.
It's also well known that an engine knocking is not a good thing. Any mechanic /technician will tell you that, and to refer back to my point earlier, why do you think your car has a system in place to protect the engine from knocking ?
or are you saying that Seat knew better than every other car maker and decided to not bother having one ?
One reason seat probably doesn't say you 'must' only run your car on 98, is because there are times, maybe if your out in the sticks or touring certain parts of Europe, where higher octane fuel is simple not available, so the car has to be able to run on a lesser grade fuel, and the cars engine management system can compensate, but it's not ideal for the reasons I stated earlier.
Now I can't comment exactly on what seat say in the cupra handbook as my seat is a diesel, but I've had many high performance cars and most of them have specified a minimum of 97 octane, or above and whilst they go on to state you can use 95 octane (or even 89 octane in one case), they don't recommend it unless absolutely necessary and only if 97+ is not available, a couple even explained the reason why, although most didn't, probably because it's pretty boring stuff even for a handbook.
You also stated "that's why Seat don't say that you 'Must' run 98 on the fuel filler flap or in the manual"
But just because Seat don't say that you 'Must' ,that doesn't really mean anything, as Seat also don't say that you 'Must' use a Seat engine oil that meets X specification, they only 'Recommend' that you do, but what they really mean is you 'Must' because if you don't , they will most likely not honour an engine related warranty claim.
Anyway my original post was simply for information on what the car does if you run a different octane in it, in reply to another members post, that's all, you can believe that's how it works, or don't believe that's how it works, it's your choice. Everyone is entitled to their opinion, but if your only going to just say rubbish to a post, then at least come up with a good reason why you think it's rubbish or maybe even some facts, the internal combustion engine has been around for well over a 100 years, so there's no shortage of information to be found.
More importantly though, Forum's can become boring pretty fast with out debate and if the only reply is to simply rubbish something