I see a dyno above doing 283whp on race gas. It could probably do even more on e85. I'm talking pump, which I guess I should've specified "without exotic fuel" but whatever. Terry's software tune bumped it up by 30whp on 93 pump gas.
Listen, I drive a car with a 2.5 liter that can JUST hit 300whp on the stock smallish turbo, and the n20/n26 is far more efficient than that car.
However, the turbo in the n20/n26 is a TD04-LR6. I can't find much on the wheel sizes, but this turbo has been around for a long time in it's core form. If you notice Terry isn't shifting the peak later into the powerband - that turbo is capping out at 5500 rpms or so. It is NOT a big turbo. You can find a flow chart on it's efficiency pretty easily.
I'm just challenging the idea that 300whp is going to be easy with bolt-ons on pump gas. I think the turbo and probably fueling requirements are going to cut into the idea of "DP, intercooler, tune" on pump gas.
I could be wrong - I'd love to be - just adding a dose of caution.
01 m5 - 127k miles 11/2013....08 535xit - 94k miles