Hi Feautos:

___There are two mods that can help a bit during the colder winter months to attempt restore some of the FE you may have received in the spring/fall. These are simply called Warm Air Mods. You have the Warm Air Intake (WAI) which is an air intake hose drawing its air from near a CAT shield or the exhaust manifold vs. right through the front of the car (possibly after a radiator). This mod usually gives you about 10 - 25 degrees increase in AIT’s vs. drawing through the std. intake depending on how good your WAI mod is. The next is a Radiator block which helps maintain coolant temps higher and blocks off some cold outside air from coming into direct contact with much of block. These 2 mods will not get you anywhere near 100% of you summer time FE but they might help maintain Leanburn at 20 degrees F and below in an Insight or HCH or give you back 1 - 2 mpg in everything else. Cost? About $10.00 for both. A WAI can be fabricated from a specific diameter - pre-heater hose available from your local Napa store. They usually come in 18” lengths and you may need (2) cobbled together depending on where you are grabbing the warmer air and where the intake hose comes into the filter canister. The Prius II for example has its exhaust manifold near the intake so you only need a short piece and your set. Radiator blocks? Just go cut up a piece of cardboard and slide it in front of the radiator. The Insight actually has a runner or shelf on the bottom that the cardboard can rest on. You may want to cut up the cardboard for a more custom fit. I had a few corners angled off, some of the top angled back, and a slot for the hood release to slide thorough which worked like a charm for the time I owned her. Ease of install and removal? A 7 year old could do it after the initial install. You can remove or install both the radiator block and the WAI in about 20 seconds once you have your initial placement of the block and the WAI hoses all setup.

___If you are primarily a city driver, the radiator block is not really recommended. I have seen coolant temps hang in the low 220’s and still climbing slowly in an all city environment vs. low 190’s while out on the highway in the Insight 5-speed. Without the Radiator block, low 170’s was the result … All in 32 degree F temps and without FAS’s or straight AS’s to test out its capabilities. If you are a primarily highway driver, I left my radiator block in all the way until it was 65 + degrees Ambient. The WAI was left on year round.

___Finally, while it’s still warm (70 + degrees F), find a shallow downward slope that levels off near your home. Maybe your driveway possibly? Shut the car off while stopped at the top of the slope and release your brakes. Take note of the exact spot that the car stopped at on the level portion of the road after the downhill coast. Now do the same when its 45 degrees, 32 degrees, and again at 0 degrees F. At 32 and 0 degrees F, you may not even be able to get the car to begin the coast down the hill depending on how steep it is! What you will see is that your coasting distances decrease with each respective decrease in temperature. This cold grease, higher mechanical friction, higher RR of your tires, whatever effect vs. temperature is huge and you cannot overcome this with any mods that I know of unfortunately

___Good Luck

___Wayne R. Gerdes
___Waynegerdes@earthlink.net