You generally have a swirl pot in the system when the original tank was designed for a non-fuel-injection system
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- which obviously doesn't have a high pressure return.
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The fuel returned goes straight back in the tank will tend to aerate and warm up the fuel already there.
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.
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.
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not a good thing.
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The swirl pot lets the fuel cool slightly and also return to the tank under a lower pressure
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(not squirted straight in!).
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Fuel injected cars will already have a tank designed to cope with a the return line of a fuel injection system.
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It tends to be older, converted cars, or those with alloy racing tanks that have external swirl tanks.
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Of course, there are also swirl tanks for water.
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.
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.
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which you generally see on Cossies and other modded turbo cars.
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.
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.
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but thats a completely different thing.
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