Give Paul a call at FBG. Tell him what you are planning to do with the bike and how much power you plan to make. They should be able to give you an idea on the head and transmission. He should also be able to get you in contact with who ever is doing cranks now. You could also call R&D and see what they have to say about the transmission. Running just on a dyno, I am not sure what you could get away with at 300 HP.
Make sure you ask them about the prices.
Not sure about the turbo and single carb. 300HP will need some fuel. The stock chassis makes it pretty limited what you can cram in there. Look up the curves for the FF, then compare them with a Garrett. Then see if you can get it to fit. The Rajay can move some air for it's size and there is always nitrous.
Oil system should not be a big deal for you. The bike is not moving. No starting or stopping. I started out with an oil cooler but it did more harm than good. Just make sure you meet the flow and pressure requirements at the turbo.
May be easier to just tell people it's a 300 HP bike and keep the money. Buy some used parts to go along with the story. Still has to be cheaper than actually making 300 HP on a GS.
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