I'm looking foward to hearing what you find out. They claim 10% fuel economy savings; I'll just jump to a conclusion and say I don't believe that one. But if their goal was to get me interested, then the trick worked, because now I'm curious.
Howe's claims 4. 8% fuel savings on their MPC, with a money back guarantee. I'm still testing, but cooler weather and recent mods have changed my baseline mpg, so I don't have any conclusions yet except to say that I don't think mine went up 5%. The test data they sent me was basically just "we drove big trucks a bunch of miles over the same roads, and the ones with our additive got better mpg. " No mention of how they controlled average speed of the two groups, and the way they worded it I'm almost sure the drivers KNEW their vehicle had the additive, so the test would not be accepted in scientific circles. If LDL, Stanadyne, or anybody has better test data, I'd like to see it. Stanadyne has some good independent lab data on pour point and lubricity, but nothing on fuel consumption. For now, I'm continuing to use additives as insurance on the lubricity issue. It adds to my cost per mile, but if the injector pump goes an extra 100k, or even 50k, it will be money well spent.
(So far, I've tried LE, Standyne, Howes MPC, and found no mpg changes greater than the normal variation you see from tank to tank on any given fill-up. I think maybe these high mpg claims are based on sticking additives in older engines with fouled injectors, so with my "young" engine, no change can be seen. )
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