Mechanical Power vs new engines???

[CheddarCheese]

Hello i had thought about this multiple times an have never really came to a complete conclusion.
So ill give a little backdrop on my experience an then i would like for anyone to chime in theyre thoughts.
Why do Mechanical engines that are turned up feel so much more aggressive than newer high hp engines?
Ive driven a 2017 peterbilt with 550 hp 13 spd with 3:55 rears, an the counterpart a 1978 Freightshaker with a Built Small Cam Cummins estimated at 400/425hp 13 spd an 3:36 rears. Both were my daily drivers for work over years an the mechanical Cummins swept the Floor with the newer 550???
It picked up speed faster, it pulled stronger an would really just get it.
I feel the same way about these older MB diesels, I recently deleted the cat and muffler and that alone made my 300sdl come alive an run cooler even mashing it at WOT.
Does it come down to suspension an the driver is actually feeling the torque more through the seat & sterring? Because the newer trucks/cars are so smooth and fast and dont transfer that much energy to the drivers seat?
Theres like a slightly harsh omphh to the old mechanical pumps that you just feel the actual power. My brother in law owns a 2017 F250 it has 495 hp an is really quick, he also has a 97 Souped up Powerstroke, he guesstimates its around 400/450 hp but ive driven both, one feels Fast and the other feels like holy **** hold on now!!!
Or Does it come down to the Oldies are operating at a higher level of its stock performance rating that once increased? You can actually feel it more???
I also Ponder about this .

Also ive driven many many Semi Trucks been driving for 20 years from all different makes to now a 2020 Peterbilt Paccar 475.
The mechanical ones just felt stronger as if they had more Power even though HP rating was lower??

[t walgamuth]

Fuel economy is king in truck engine design. The new fuel injection system is so sophisticated they don't make much noise.

On my 39 stude with the 617 turbo it is very quiet with a straight pipe...not caddy like but still very easy on the ears. Sometimes you get some turbo whine too. Sounds like a baby Cummins.

[moon161]

I think you're mostly describing NVH, Noise, Vibration & Harshness, which car makers mostly try to minimize.

[pawoSD]

Just depends on the tune/settings on the vehicle. My Metris is a....van, and if you punch the throttle it will readily squeal the tires and throw you back (especially if traction control is "disabled") My GLK doesn't feel as aggressive as my E320....but both have similar acceleration performance.

The old cars feeling faster is mostly just a perception thing, they're less refined.