[Boynamedsue]

Understandably toyota spends alot of money on their engine research every year, but they also have a raceing devision and sell aftermarket parts. If i were you i would buy the TRD parts. they arent going to give you a car that runs at 100% efficency(you would have people blowing up camrys left and right) people can knock them or whatever but they are designed by toyota and i think they know what they are doing. most vehicles operate at around 79-82% power eficency so they hold up longer but still have good power. most of the missing power can be put back by tuning the fuel and timing tables. Exhaust systems have more time spent on them than anything in order to keep noise down but still flow good. Personally unless you do something to the vavletrain on increase cubic inches its a deadend street. But intakes are extremely restrictive in order to keep noise down you can get power from them.

Improving systems that are in place will bring out hidden power. only when you change parts like cams intake manifolds ect. will you MAKE more power. I think with a proper tune and a less restrictive intake the 5.7 could make 400hp and the tuning would still be fairly mild. the 4.7 could make about 290