So I thought I'd start this thread so people could post up their tech how-to's on gaining hp and economy. Most people already know about airing up the tires, removing extra weight, etc. But what about things like this:
When I was changing the timing belt on my 03 4.7L Tundra I noticed there was a little hose leading from my cooling system to my throttle body. After some investigation I discovered that the great engineers over at Toyota set it up that way just in case you live in Alaska. You see without the heat of the coolant the throttle body could freeze up. Since it rarely gets under 50 degrees here in San Diego I un plugged the feed line to the throttle body and plugged it into the return line completely bypassing the throttle body. Since the IAT sensor is in the MAF the cooler air isn't noticed by the computer which allows the truck to run a little closer to 14 to 1 a/f ratio. This helps a little anyways since Toyota sets these trucks up to run close to 10 to 1! Now after pulling a hill I can put my hand on the intake manifold and it's actually cold. It used to get so hot that it would burn your hand!
This mod combined with my DirtyDeedsIndustries.com electric fan conversion, and drop in K&N was good for about 20HP to the wheels, as shown by one of 4 dyno runs.
When I was changing the timing belt on my 03 4.7L Tundra I noticed there was a little hose leading from my cooling system to my throttle body. After some investigation I discovered that the great engineers over at Toyota set it up that way just in case you live in Alaska. You see without the heat of the coolant the throttle body could freeze up. Since it rarely gets under 50 degrees here in San Diego I un plugged the feed line to the throttle body and plugged it into the return line completely bypassing the throttle body. Since the IAT sensor is in the MAF the cooler air isn't noticed by the computer which allows the truck to run a little closer to 14 to 1 a/f ratio. This helps a little anyways since Toyota sets these trucks up to run close to 10 to 1! Now after pulling a hill I can put my hand on the intake manifold and it's actually cold. It used to get so hot that it would burn your hand!
This mod combined with my DirtyDeedsIndustries.com electric fan conversion, and drop in K&N was good for about 20HP to the wheels, as shown by one of 4 dyno runs.