Right, my mistake. I meant 89. I dont think 85 is even available anymore. Thanks

 

Only 93 octane since 2001 and get 16 MPG, more with Restore, fuel additive.

 

i get about 12ish, but thats according to my over head console! not sure how accurate that is!

 

So after new plugs and some Lucas Fuel treatment in the tank, on a 350 mile round trip, I got 15.4MPG. better but I will do a TB clean soon (as soon as it stops raining) and prob. K&N air filter for the time being. Any tips on a "TB clean job" would be helpful! Any gaskets or anything I need to be concerned with or anything like that when doing TB clean? Is K&N drop in air filter ok? Any other suggestions are welcome too!

 

TB is easy to do, no gaskets needed. Do a search on it if you have any trouble which I'm sure you won't. Use a good quality brake cleaner. I had to actually chisel the gunk off mine it was so crusted on and then did a good clean with Brake fluid. Just watch that TB connector and don't break the red clip disconnecting. Slide the clip back and pull the harness in the same direction at the same time. Good luck

 

Well got my TB all cleaned up yesterday, and in the process I probably found the major source of my MPG problem, the plastic box that sits in front of the TB was not correctly placed. There was only one of the two bolts screwed down and the blue rubber flange type gasket thing (now that's a technical term) between the two was showing! anyhow it is back together now and though it has only been a few short trips I have noticed improvements all the way around!

 

I just picked up my truck this past friday and have noticed so far that I'm getting 10-12 city and 15-16 Hwy ... which i don't think is too bad

 

I've said it before, the brown burn marks are normal for the copper plug as the are too hot for the Hemi IMO. I tried a new copper set once and the gap grew on it's own only after 3 months (is the gap oversized on those) and I was using 87 as prescribed w/o the amendement suggestion to use 89. Since then I changed to a better plug, one you can leave in longer than 30K and have piece of mind that the Gap remains as you set it. Try one temp colder and then check your exhaust pipe in a week or two and you will have less black soot for sure.

 

Yes the gap was way over on the old plugs....I am considering putting new plugs in (again), in about a 3 months or so. I put the exact plug that came out, back in. My theory of that was that I wanted to get the truck as close to stock everything and fix MPG first to find out the cause of poor MPG. Now that is done (I think)....I am going to change all fluids and start performance upgrades. Just curious what plugs did you get? all tips welcome!

 

the hemi like stock coppers the best. either champion or NGK. for some, the fancy platinum or iriduims work fine. but there are plenty of others who try them, and they dont work well at all. there are no performance gains to be had by spark plugs.