A diverse range of comments and opinions as to be expected but taking a slightly biased view here's my take on things.
Like it or not we will always be tied to what is happening in America as that is where the sport as we know it was born and it is where we get most of our equipment from, drag racing is so small in Europe compared to other Motor Sport it would be an uphill struggle to try and go it alone with home bred rules that do not have a direct link to an established and accredited organisation. That being said there are significant differences between the recently published European rules and the current Heritage Series rules which make sense in an emerging class.
The reason the current US cars are turning such high RPM is a direct result of the limitations on both Blower size / overdrive and pump size - to overcome the limitations the teams in the States are building smaller capacity motors (to reduce rotating mass) and spinning them higher in the rev range (by using lower ratio rear gears) to get the air & fuel delivery higher (this is also why they have started using "Pedal Clutches" so they can "up" the idle fuel delivery & pressure at launch). This is the same thing that happened in NTF a few years ago and you are now starting to see the same result through the traps.
As for a Methanol car costing less than a Nitro car, Body & Rolling chassis costs are identical (apart from an extra £200 for a chrome molly motor plate) as they both are the same SFI 10.1E specification. Engine build costs are pretty much identical, bellhousing and clutch costs are the same, transmission costs are actually less for a Nitro car as a 2 speed Lenco is cheaper than a 3 speed Lenco. Supercharger cost is near identical if you are really talking Nostalgia (i.e. pre 1979) as a standard helix 6/71 is about the same as a standard helix 8/71. A points magneto is cheaper (by about 2/3) than a 44amp mag and fuel pump costs are only about $300 apart (providing again you are talking real nostalgia and not the modern gear pumps). Driver safety equipment is the same spec for both as they are both front engine with transmission in the car, so I guess the main "cost" difference is that many people have equipment that doesn't fit in the rules so for them the cost is perceived as being higher as they would have to buy something they "already have".
As Rob said the rules do not come in until 2016 so until then the methanol cars can run alongside (although I'm not sure there are 4) if after that if they want to sort out some rules then they could start their own group.
Do you need a 44amp mag - not really, ours is about 5 amps, do you need a modern gear pump - ours is an Enderle 1200 (probably cheaper than some of the pumps in Super Pro), we run a big capacity, slow revving motor (probably never gets over about 9000rpm) and it's had the same valve springs in it for the last 5 years. Sure we hurt parts - pistons being the main "consumable" but probably not as many as you may think.
So from where I sit the only cost difference between a Methanol car and a Nitro car is the running costs and of those the only significant difference is the fuel as they both use the same amount of oil, both have 8 plugs and we don't see any more bearing damage than when we ran methanol - but the smile factor with NItro is so much more

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