I've had a couple of shops tell me they could estimate my 1/4 mile time within a tenth of a second. Can anyone tell me how accurate this can really be?

 

They might want to get a crystal ball instead of a dyno. There is more to horsepower and torque that comes into play when making as pass. Driver skill. Track prep. Weather. They can make a prediction but they aren't going to be able to hit the nail on the head without a ton of luck!

 

I'm guessing those shops would have the OP or one of their guys do a quarter mile pass on the dyno and then calculate their estimate. If you're getting a dyno tune for that throttle "lag" and etc, I would be curious what their estimate would be if it didn't cost anything. Still an estimate though like running a treadmill to guess a 100 meter sprint time....you won't know until you make a pass at the drag strip.

 

I've seen a could of the new 5.0's dip into the low 14's. Like blue said HP and tourque are just part of it.