Do both of yourselves a favor and take it to the dragstrip. If you get pulled over racing I can tell you 2 things. One, if you beet him, he won't pay up. Two, you will end up out the $1000 even if he does pay up. (ticket, insurance premium, and possible impound)
On a strip a good driver of an SRT4 in bone stock form on street tires can run high 13's. With the mods he is claiming (not sure who the hell actually runs 4inch exhaust on an srt4) On street tires he could possibly run 12.8-13.2 if he's a good driver. A good srt4 driver > traction. Now if he's a crappy driver, he will run 15's all day long.