I've been running a V3 on my '02 7.3L Excursion for about almost a year now (20K-ish miles) and I love it. It's really more about whether or not you want to be a oil-burner. It takes some effort in the beginning to figure out collecting and filtering, but I don't find it difficult at all any more.
I collect in cubies from three restaurants, then I use a settling system with a WVO Designs centrifuge to clean the oil. Then, it's just pump from my 275-gallon clean oil storage tote into my 40-gallon undercarriage tank and away we go. The Vegistroke I have is fully automatic, so my wife isn't really intimidated by it at all - which I really like. I know they sell less-automated versions as well. (
Dino Fuel Alternatives | Alternative Fuel, Vegetable Oil Fuel Systems, Vegistroke & Bio Diesel)
I got the PHP Gryphon and am running Bill's 80HP Performance veggie tune that he customized for me to burn Veggie about 99% of the time. I also have a 65HP Tow veggie tune and a regular 80HP Performance diesel tune loaded in there at the moment. For me, it was worth a few extra bucks to get a veggie-specific tune. It is not drastically different than the regular diesel tune, but enough that it matters to me. FWIW, I taught my wife how to use the Gryphon, too, and she has no problem with it either.
I don't notice any power loss between vegi and D2, but I believe there is some small amount - like 5% range. There are a few people who have documented this with Powerstroke motors on actual dyno runs. Also, I get 1-2 mpg less mileage on vegi. I have been averaging in the 16-18 mpg range... but I like throwing the Ex around a bit. Highway mileage is much better.
I took a 4300 mile cross-country trip shortly after my install and only burned about 15 gallons of diesel the whole way - the rest was all veggie oil. I am taking a 2500 mile trip around Easter and hope to achieve the same results.
PM me if you have any other questions you want to ask.
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www.VibrantLED.com -- '02 7.3L Excursion Limited ~135Kmi total; ~50Kmi on WVO
Vegistroke V3 (installed 4/09); HIH, Aux Pump, FPHE (added 11/10); WVO Designs CF
PHP Gryphon; 6637 intake; 4" exhaust; Terminator HPOP; Tru-Cool; Evans NPG+; other goodies...