You can put a crazy amount of horsepower into the Datsun with an engine swap and a few other mods. I think it's pretty stupid to have a little car like that have the potential to be so fast. I get mostly 8.5xx in my veyron and haven't had a datsun come too close yet, but I know there are fast ones out there.
You know, when Jesus died it took him 3 days to respawn. Thats what i call lag. o_O
The Datsun can be made to be the fastest (or 2nd fastest) drag car in the game. Why? Because it's very lightweight and you can put engine+drivetrain in from much faster cars such as the Skyline. Might not be the most realistic experience but the Datsun IS that fast in-game.
The veyron is the fastest but not by much over the datsun. 2000lbs and 950 hp will tear up the drag strip. The topsecrrt supraand the Mazda B06 can be almost just as fast with a skilled tuner and driver.