Interesting topic. When I built my Chevelle, I initially put together a 500hp 6 liter, that I was sure would supply all the power I ever wanted in the car. I was sure I’d never want, or need more. Lol...
The car gets drove very little, but when it does it’s a pretty day. I live in an area that is very rural, in the north Ga. mountains. Lots of twisties, and hills, combined with straightaways that go forever. It’s a cool place. Best part is there’s little population around here. Don’t see much traffic, if you pick the right time, and the right road. It’s easy to stretch your legs around here, if you know what I mean.
I get bored easily when I’m not waist deep in a project, so I set out to build another engine last year. I planned it out, budgeted it all, and went to work. It’s a pretty max effort deal that made 616 two weeks ago at Vengeance. I’m dealing with wideband issues, and my ECM is back at Mast right now. When I get the wideband working right, I think I’ll pick up another 25ish.
The engine is a 434”, and I went with a big camshaft (solid roller), but not too big for a 434”. Cubic inches absorb camshaft well, so it’s actually very driveable.
What’s too much power? I don’t know the answer. I plan to pull it back apart in a couple years, change pistons, throw an efficient blower up on it, and shoot for 1000.

I know my truck doesn’t need anymore power until I can get more traction.

Too much? I would say in the realm around 1400 rwhp. At that point, it is a true pissing match.

Everything else in the garage, I want to keep in that 1000 rwhp to 1200 rwhp realm.

What setting we talking about? Potential double duty car? All I can say is its a tragic day when a fully ported polished pulley'd down zr1 blower on your average run of the mill built ls motor isn't enough power to even hardly get noticed in a bigger city at night😫. Admittedly auto cross/road race type stuff is a vastly different story concerning poWer necessities. But if you're that person that also happens to enjoy occasional late night trips to the streets of Mexico, 1000whp just feels like the standard. Not that I condone that in any way. Race at the track, eat your peas, all that kids...

It depend on just how much you can handle .versus reliability.My 300 HP 350 in my 1981 El Camino SS is my daily driver .Of which I can drive in most any weather.Then I have my "toy" .My 1979 Z-28 RS Camaro. It has a 500 HP plus supercharged small block Chevy.Of which is gas and traction related.by just adjusting the boost level.

That's the real question: what's the purpose of the car?

I've questioned this same issue myself, so here's a more specific question:

3,200 lb car
~45% rear bias
4-link or torque arm set-up for street/autocross/HPDE (in that order of priority)
TrueTrac diff (maybe a locker)
Manual transmission
Street tires in the 200 - 340 TW range

How much power can you really get to the ground without having to constantly feather it?

Where I've landed is 450 - 500 RWTQ, 500 - 550 RWHP aiming for the higher end on torque and lower end on HP so you don't kill the low RPM power. My thought is to do this with a short/medium runner intake, properly sized intake/exhaust ports and picking the cam accordingly.

Interested in feedback.

This was my thought too. I know I won't be racing on the streets or at the drag strip for that matter. I also know traction will be the limiting factor for me. I just see all these stock cars coming from the factory now with 5-700hp and think thats what I need.

My 66 chevelle will not be daily driven, but it will see its fair share of the road and I plan on driving it a good amount. This car will not be sitting in the garage to keep pristine.

Right now my thoughts are to go with an LQ4 or LQ9, install a BTR stage 3 cam, and some LS3 heads. I will have a t56 for a trans and 3.89 rear gears. Maybe further down the road when I get that itch for more power I can throw a supercharger on it.