His isn't completely straight piping. He has apexi piping as well so the sound is different than a straight pipe.
I was thinking about getting a straight pipe exhaust, but I dont know if there really is much of a difference from other exhaust systems. If anyone has one, please let me hear your thoughts on them. I was thinking about getting something like this
http://www.canibeat.com/wp-content/uploads/2010/04/4464479508_3dc99c0112_o.jpg
Straight pipe can be interpreted two different ways:
a) literally a straight pipe (which is impossible due to a FEW needed bends in our cars unless you're dumping it straight down to the ground after the header).
b) pipe with no cat, resonator, or muffler - straight from the header.
My usual understanding is option b, which is what Kevin (Doctor X) has. The fact that he has Apex'I piping makes no difference - piping is piping. The only thing remotely close to making a difference is how the piping was bent - mandrel or crush, but that's only if you want to get real technical.
If its straight there should be no bends and the only difference would be in the metal used for the piping ie titanium
He was the master machanic in Toretto's "team"