The wrapping of 3/8 copper tubing around the upper radiator hose done on a pipe form and slid over the hose. Was an example of pre heating the fuel on a vegatable car I changed back to diesel.

There might even be a slight milage gain by using prewarmed fuel in the winter. It was neatly done on that example. Looked like he used a whole roll of that 3/8 soft copper. Would not be hard to duplicate..

To neaten up this one might take a section of larger hose of some sort and slide it over the coil. This would also tend to trap more heat in between.