Need different type of packages for engines ? jon barrett's engines?
Mustangs would be Roush, and Saleen, suprisingly Ford has aftermarket performance parts as well. For Chevrolet, there isMr Goodwrench, Lingenfelter, SLP- stands for Street Legal Performance. SLP is the company that made the Firebird Firehawk, and they did some work on the Camaro SS as well. For all around type stuff, try YEAR-One. BMW, sorry cant help you there. I know they had there M cars, but I dont know if anybody makes performance packages for them.