Originally posted by kitesurf_phil
I too had a similar notion, even measured up the space and did some rough sketches as to the size and shape of tank I could fit there. I then figured that I could have the exhaust modified to relocate the box to where the spare wheel was, thus leaving room for an even bigger, less complicated tank under the drivers side floor opposite the original tank, this would also avoid having all that extra weight behind the rear axle. (don't know if this is as applicable to you, as yours is I believe a 2nd gen, have a look and see)
Having said all that, I've now decieded to modify the fuel rather than the vehicle and hope to be making my own biodiesel within the next 3 to 6 months instead.
With regard to using exhaust heat the concensus on most of the veg-oil forums is don't do it, this has been discussed often and at length, using a heat exchanger in the water system is the way to go. check out the forums at http://groups.yahoo.com/group/vegoil-diesel and http://biodiesel.infopop.cc
The first primarly deals with using waste oil whilst the second, despite its name covers everything from biodiesel to waste oil to other alternative energies.
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