First off, the fact that you're installing GT2835s, a V-Pro and 1,000cc injectors alone is already making the car illegal to drive on the street. What you want is a legal street car that's illegal. That's an oxymoron if I ever heard of one. To fully utilize turbos that large, you'll have to install aftermarket camshafts, but the valve overlap introduced from these cams will almost certainly fail any sniffer type smog test. Although only a few states require a tail pipe emissions test, more and more states are implementing a sniffer test. It would require a lot of tuning to ensure the car would pass a sniffer test with 1,000cc injectors and camshafts.
For high horsepower and big boost, you'll need to run race fuel. There are many very good unleaded race fuels. I use Sunoco GT+ in all of XS Engineering's race cars. GT+ has a R+M/2 rating of 104 octane and is probably the best knock proof unleaded fuel I've used so far. At the 2007 PRI Show, I spoke to a Shell representative who told me that Shell will be releasing a 108 R+M/2 fuel in 2008. Keep in mind that Shell blends race fuels for some of the top teams in motorsport including Ferrari in F1, Audi in Le Mans, etc.
As for why the high end race fuels are leaded, well that's a question for a chemist or an engineer. I was told before by a NHRA Pro Street engine builder that the lead slows the burn time of fuel by increasing the amount of time that the fuel can be exposed to heat before it autoignites. This is probably why leaded fuels seem to have a higher octane rating.
You have questions and we have answers. Well not us, per say, but Eric Hsu. Currently at world-renown Cosworth for performance parts development, Eric brings over 15 years of experience-five years as Chief Engineer for A'PEXi and a founder and current consultant for XS Engineering-to help with your woes. As a tuning guru, unlike the guy on the forums who thinks he knows everything, he actually knows what he's talking about. That is, unless your topic of conversation is about APC taillight fitments, upon which we must specify all of Eric's opinions are his and his alone. Except on Altezza taillights. It's the reverse of Nikes logo: Just don't do it.
For questions, comments, banal exchanges of your own, email them to questionit@importtuner.com.