I've been assured frequently that throttle response is irrelevant, as long as the top speed is the same between restricted larger blockes and unrestricted smaller blocks.
Charlie, what kind of motor are you asking for, other than it not have intake restrictions? Speeds at Daytona and Tallaedega are strictly a function of horsepower, aerodynamic drag, and some slight influence from driveline friction.
Current 358 c.i. pushrod engines with two valves per cylinder make about 850 bhp without restrictions (as raced in 2014). Beginning in 2015, with the tapered spacer (a restrictor plate by another name), these same motors make about 725 bhp.
With the plate for Daytona/Talladega, these motors are making about 420 bhp. Just about every year, the holes in the plate get a bit smaller to offset efficiency gains made by the engine builders. Your new unrestricted motor will need to make no more than 420 bhp to meet Nascar's speed objectives.
If your new motor is going to have similar architecture, i.e. pushrods, two valves, 8,500 rpm gearing, it would need to be somewhere in the neighborhood of 177 c.i. or 2.9 liters. Think in terms of an inline four that is roughly half of a current Nascar V-8. If you expect this motor to have quick throttle response at Talladega... think again. It is the nature of the beast under conditions of aerodynamic drag being roughly equal to peak horsepower.
If your new motor is to have more modern architecture, DOHC and four valves per cylinder and maybe higher revs, the displacement would need to be significantly smaller than the 2.9 liters. Did you seriously mean to suggest Nascar should bring in 2-liter fours for these big tracks?
If your motor is to be a 305 c.i. pushrod V-8 as was suggested above, that motor would still need a plate for Daytona and Talladega. Without the plate, you have exceeded the horsepower target by 300 ponies.
Bottom line: you are better off arguing ISC should knock down the banking rather than introducing smaller motors for these tracks.