That's the thing right there.
Fifteen years ago, it was still possible to be king of the streets in your area with a Turbo Regal and a few modest bolt-ons.
Those days are OVER. When you can walk down to the dealer and buy 700+HP turnkey with a warranty, well, you just can't keep up with that. Those cars cost $60,000+ because that's what it costs to make that kind of power and have the car be reliable. The HellCrate engine is $19K list, and I've found it for $15K out the door.
To make 707hp reliably on a Buick V6, you're probably going to spend at least that much on the engine, and then you have to fortify the entire drivetrain back to the rear tires to not shatter. Plus you'll have to cage it to keep the car from twisting like a Twizzler, which severely compromises the usefulness and comfort of the interior.
The days of putting a set of bluetops on with a chip and a threaded wastegate rod and kicking all ass at the street races are gone. If you really want to keep up with modern hardware, it's going to be expensive, frustrating, and painful.
Or, come to grips with it and either spend the metric boatload of money and effort with your eyes wide open, or move on to a newer platform. I was recenly offered a Second Gen CTS-V modified by WeaponX in Cincinatti. The car made 920hp at the wheels on nitrous and E85 on a safe tune. Full interior. Hop in it with three friends and drive to California with the heated/cooled/massaging seats, ice cold A/C, and a booming stereo.
I could have had it for $35K.
You're not going to build something like that with a V6 Regal for that kind of money. Fast, cheap, good, pick two.
I agree with you on the evolution of technology, you can't beat it. HellCats, Demons, CTS-V's are some bad ass cars, but not everything that glitters is gold. I have seen lots of them at the track run in the 11's and high 10's, and it wouldn't cost you your left nut to beat that. Project Silver Bullet on here ran in the 10's with bolt ons (long block completely stock). A lot of people don't have the knowledge to match the right parts together and tune it properly. Bison ran high 9's with his. Yes we are dealing with 1980's technology, but it is doable if done right, and reliable. Where I will shut my mouth is on the refinement, fit and finish of these new cars. The interiors are gorgeous with all creature comforts and state of the art stereos, suspension etc. The one advantage we do have is weight. A 920hp CTS-V is still a low 10- high 9 sec car because it's a heavy car without a solid rear end. 4225lb by itself without a driver makes a 660hp Buick comparable. The THS class we run on the board is some of the best examples of reliable full weight street cars we have out there running mid 9's, and you don't need a cage in our cars to stop it from twisting. Neither one of my cars has that and the lines on them are straight and clean with no waves or ripples with complete full factory interior. A HR bar is all you need. At the end of the day, it's all about the pursuit of happiness. If it's in a Hell Cat or CTS-V.....then bless you, if it's in a Buick it's all good. There is always 2 ways to skin a cat. What ever puts that smile on your face is all that matters.