Burgh I'm not kidding, if you look at the spec info etc, plus I've seen many videos of stock GTR, for example Best Motoring tests, other videos etc. they all share the time for stock GTR running the quarter mile between 12.8 - 13.2 depends on the GTR models (R32, R34 V.spec etc.).
One thing tho which is an very important facter that is all the factory tests for the GTR's at the quarter mile has been done by proffessional drivers. A poor drivers that doesn't rev propperly at the launch or doesn't shift gear correctly and quick enough (at right rev) might be loosing up to 2 seconds or worst 3 seconds at the quarter mile. A quick AWD launch with a GTR isn't easy if you don't know the technique on how to do it propperly.
Burgh this GTR weighs the same as stock with only 420 horsepower under the bonnet. He does 12 flat seconds at the quarter mile, he isn't even a pro driver, check here (Right Click Save AS):
http://upload.karel.se/T-H/Filmer/hammar.wmv