I was wondering if anyone has used the E3 plugs? Ive seen reports of them increasing performance and fuel economy, the performance part im not really interested in cause 3-6 HP ur not gonna feel (if that's true) I'm more interested in the fuel economy gains. I put a set in my HHR and they had a negative effect, I now they are completely different animals, but the claims have been universal. i have seen the "Horse Power" episode where they do test them and have great results,I just was wondering if anyone on here has done this. Any help would be greatly appreciated!