2 minutes does apply, but you have to get the first driver out COMPLETELY. Then you fuel. Once that's done COMPLETELY, then the second driver can enter the car.
Now, if you have a 25 gallon cell and a good overhead fuel rig, which we do, you can fuel the entire thing in about 50 seconds. We might be able to get that down with a double hose setup on the next car (we have one hose now and the vent is in the car, but a double hose vents through a bigger hose and will take fuel a LITTLE bit faster). But 2 seconds per gallon is nothing to sneeze at. Or smoke near.
That's if everything goes perfect. But it rarely does. You have to realistically figure you've got about 50 seconds left of the 2 minutes to get the second driver in and fully buckled. That would be cake if everyone was a professional on the same team every week. But since we're not, we've generally been a LITTLE tardy in the RSX. Anywhere from 5-10 seconds, which isn't a big deal (so we haven't worked on it much, either). With more work, we could probably get a ten second cushion, maybe. But part of that is thanks to a big door and easy access to everything. With the RSX we extended the steering pretty far and put the seat pretty far back (and with a separate pedal box that was easy). Helps with weight balance and makes using a halo seat a lot less of an entrance/exit issue, too. I don't think I could have one of those in a Spec Miata, for example, and try a fast driver change. They have them in the MER MX-5's and they seriously get in the way.
But with the bigger fuel cell comes the need for faster driver changes.
Jason, believe me, I know about the 500HP in a box. I'll be buying something similar for my next One Lap car, most likely. But it won't be in a Vette. More on that as it develops.
--Donnie