So, I was showing off my new truck to my brother-in-law this evening. He's a gearhead and has a souped up Camaro. I asked him about the best bang for the buck performance mod he'd suggest for me. He said an underdrive pulley would cost about $30-$40 and get 20+ HP and low-end torque by putting less of a load on the engine. He did say that when you're idling, you are pulling partially off the battery, so it'd be a problem in regular bumper to bumper traffic. Since I have the towing package, which includes a beefier alternator and battery, he said it's not a big risk.
This is the first time I've heard of this. Anybody tried it on their Tacoma? Too good to be true?