Turbos are nice, but to make extreme peak HP with a small engine you give up low end, thats why 900 HP Supras are only turning out 10 second quarters, with an NA car you can do that with a little over 500 HP.
Here is what I put out RWHP numbers, I had an ignition miss so I'm short at least 15 HP since I'm missing 600 RPM or so of what my peak was supposed to come at. Street legal shorty headers, stock bottom end, daily driven and naturally aspirated.
1968 Shelby Cobra GT350 or 500KR in Acapulco Blue with white le mans stripes convertible with a white top and black vinyl interior. It'd also has to have the Shelby 10 Spoke Rims and 4 on the floor. THAT is a car.