You jest, and yet...Lol I guess I'll just get a polestar
Funny thing is the same is true with the P2 R cars. People do a moderate turbo upgrade, all the typical plumbing bolt-ons, and their automatic P2 R still only runs the mid-high 13s in the quarter mile, same as a bone stock 2013+ S60 T6 R-Design.Agreed. I have my 2005 2.5T up to about 315 hp~ and it's had a decent bit done to it. 19T turbo swap with all supporting mods (exhaust, FMIC, injectors, intake, fluids, etc.) and it is faster than stock... but it's still not a manual which is bumming me more and more, but also doesn't have much room for more power without a lot more money. It already cost a decent penny to get here, more than it would have to sell my car and buy an S60R with/without manual (don't know your preferences).
Great advice and well said. If you can't afford any of the 300HP upgrade paths (parts or new car) just get the "cheap" plumbing bolt-ons and a tune and just be happy with the HP/TQ you end up with.Also go for torque not horsepower.
To actually answer your question, bolt on a bigger turbo, downpipe, large intake tube, and FMIC, then tune it for the parts you buy and you'll break 300 ft-lb easily. The power will be in the high 200s but again power doesn't give you a good 0-60 time, torque does.
You can get halfway there with just a tune and no other mods.