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Engine basics => Engine set up tips => Topic started by: Steve Fitton on December 14, 2010, 01:22:50 PM
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How many of you guys run some sort of heat shield or baffle to keep heat from the header off your fuel tank?
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Hey Steve - Always. Mine is a 1/4 inch slice of foam, encased in a plastic bag, under a shield made of .010 aluminum roof flashing. Use servo screws to hold the shield, insulation and tank in place.
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Hey Steve - Always. Mine is a 1/4 inch slice of foam, encased in a plastic bag, under a shield made of .010 aluminum roof flashing. Use servo screws to hold the shield, insulation and tank in place.
Can I ask the obvious 'why?'
I assume that heat radiation is the issue here but in flight with all the air flow around the header how much heat would really be transferred?
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Hi Steve,
Randy never told me to, and I never saw one on any one else's so I haven't. Not being a smart alec, but ever since I started using pipes around 1994, I never thought it was necessary.
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How many of you guys run some sort of heat shield or baffle to keep heat from the header off your fuel tank?
Steve
Think sewer pipe...clean tube from front to rear..air comes in the front...passes the motor..header..front part of the pipe...exits the rear..does not exit up front or before the middle of the pipe or rear muffler...2 times exit vs. intake air.
The air will keep the tank cool unless the header is touching the tank..then nothing will ever run right.
I have never used any heat sheild, Tried one once but it had zero effect on my setup, Most everyone runs without a heatsheild, so try it and see how your system works with or without
Randy
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I have the same problem that I think Steve is having. That is, with the tank I like/need to use there is very little room between the header and the tank. I have to keep a constant check on mine and it does have a tendency to touch if unchecked. (even after hitting the tank with a hammer to make room for the header) Last time I opened the Dreadnought they were touching, had to take it all apart again. I may build a tank that allows for the header.....
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I went to shields after having mixture changes in flight. If it goes richer as the flight progresses, the header is heating the fuel and tank, lowering the viscosity so the NVA flows more fuel. Much the same effect as having to change needle settings with changes in ambient air temp. I do agree that it is unnecessary 95% of the time. Its the other 5% that bothers me.