If he's a cracker, or you are planning on using it, then I cannot help. Crackers should be shot, poisoned, hanged, drawen, quartered, spat at, and mocked. Only a complete IDIOT with several incest related genetic disorders would crack LFS.
Yes, you can with the XRT. But as you don't have the XRT in the latest patch, can't use LFS Tweak as a demo user, and don't know what setups to use, the odds are stacked against you at the moment.
First thing - buy LFS. Then you can do what you like (within reason).
He might be using LFSTweak, which is a program that changes the car stats like HP, mass ect. I think it is stupid because you cant use it on line anyway.
When I used the Demo servers everyone who crashed said they were pissed or stoned, cos its looks good for the street cred, personally I think little Bro above thinks hes making his Big Bro appear street wise in suggesting he cracked it, I vote he bought it.