|
Welcome to the site Creeper.
I hate to say it, but I highly doubt your pulstar plugs got you a 4% increase. I've seen a lot of guys use them and nobody has ever seen a noticeable increase in fuel economy, including myself. Also, one of my failed after only 1 year of use. Thankfully I didn't dish out the $ for them as it was a free trial. If I had paid for them I would have been very upset.
As for tire pressure, I'd air the tires up up to max sidewall pressure. 1-2 psi won't do much to decrease rolling resistance.
I do like synthetic in the engine as well as the transmission. In winter the synthetic tranny oil made a noticeable difference in coasting distance before the engine was warmed up with. The engine oil I don't think does as much, but it does allow for extended oil change intervals which reduces oil consumption.
If you are doing mostly highway driving, I wouldn't concentrate so much on weight reduction as I would on aerodynamics. You'll see much better gains there.
|