So I've had a GX470, and a 5.7L Tundra and I will say that owning a GX460 with the 4.6L has kind of made me miss both of them. The low end grunt that I'm used to I just don't get out of the 4.6L so I'm out to see what I can squeeze out it to help kick it in the rear. My truck is a 2011 base model with 92k miles on it and is my daily driver. Covering the basics: (aka cheap stuff, none of these are big HP mods) 1. Swapped out the factory long life iridium spark plugs for a set of NGK IX series iridium plugs. I was getting close to the 100k service interval anyway. I can see some of you scratching your heads at this point. The IX series iridium plug use a different style ground electrode to help keep the spark from being shrouded from the incoming mixture, helping the fuel charge ignite faster. (If you're ever bored spark plug tech is crazy!) 2. Swapped out the Air filter for an AFE Pro Dry drop in filter (I don't use oiled filters in MAF equipped cars) and removed the Hydrocarbon trap (the filter stuck to the inside of the air box lid) I know the Hydrocarbon trap removal is a much debated thing but if BASF thinks it effects HP and MPG they probably have the research to back it up. They state this here as they have come up with a better way to do it. 3. Exhaust is next. The exhaust system of this thing is bottleneck and a half. Yes I understand noise is a big concern for the engineers but this qualifies as the minimum piping diameter needed not to completely strangle the engine. Since I live in CA I am limited but there are ways around it legally. Just Ideas at this point: There are CARB approved shorty headers for the 4.6L Tundra which would enable me to get rid of the one piece log style manifold / catalytic converter and run the Tundra front converters. I would have to have the paperwork to show I "swapped" a same year or newer Tundra 4.6L into the GX. This would allow me to redesign the cat-back to a larger diameter, free flowing design. If any of you have managed to get a little more go out of the 4.6L I'd love to hear about it.