I have made a LOT of n00b errors over the relationship between me and my Civic. I have a 97 Civic EX with 152,200 miles and is in need for some service: -Tranny (most likely synchro going out, maybe clutch?) Grinds from 2nd to 3rd gear if RPM above 2k. Sometimes kicks it out 3rd gear when rpms lower to 1k. - Brakes are another issue; pads, rotors, lines, fluid each are about 4 years old. working fine! - Has HP racing 4to1 solid piece headers, KN oe box filter, pacesetter hi flow cat, 2.5in piping after cat, and ahem.... stock muffler that insurance put on after an accident. - I use quaker state synthetic 5W30 with Quaker State Oil Filter. (every 2700-3000mi) - Use Marvel Mystery Oil every 3 fillups to clean injectors, fuel delivery system. - AEM fuel filter and housing. - Stock distributer but with bosch rotor, cap, and nology hotwires, about 1 1/2 years old. - Always keep tire pressure at recommended levels (30F/29R) - Tranny Fluid was changed 10,000~miles ago w/ valvoline 10w30 Standard. - Stock Steel wheels (hubcaps still on yea!) Goodyear Viva Touring Rubbers - besides a Sony Xp 60x4 Headunit and two polkaudio components in the front..(see below) - this car is stock. My Question: I know there is a good deal of work to get done to make this car run better. It runs great right now but I know there are ways to do a lot more out of it. I average 34mpg @ 70mph, and around 25-30mpg in town/freeway usually driving back and forth to work. A new engine or Forced induction are out of the question. Thanks. What types of performance upgrades can I perform that would reduce gas consumption and add performance? Cold air Intake? a new muffler on? A tune-up of course but what recommended parts? Any chemicals or services I should go thru (ie. oil systems flush)? Lighter rims? Pulleys? Pull out your knowledge and help me find ways to have a more "green friendly" performance vehicle.