[mwilliamshs]

A thread about gearing options should include tire options in my opinion. Being new to the Honda thing and new to wheels smaller than 15" in general, I'm ignorant of what sizes are available to fit my 98 Civic. Here's what I do know: for best efficiency a narrow tire is better than a wider one and a taller tire is better than a shorter one. Obviously a tire so tall it raises the vehicle and allows excess air under the vehicle would be bad and a tire so tall it moves the engine out of its best rpm range at cruise speed would be bad and a tire so tall it is excessively heavy would be bad. Also keep in mind tire diameter changes will alter speedometer and odometer readings as well as those of a scangauge, etc.

All that being said, my 98 Civic's OE tire size is 185/65-14. A better option in my opinion is 175/70-14. For simplicity's sake I'll discuss only Michelin Defender tires because they're available in both sizes and the only other I've found in both sizes is a T-rated General that I wouldn't buy. The 175 is .3" taller and .4" narrower in section and has tread .5" narrower. The 175/70-14 being a bit taller means fewer revolutions per mile (difference of 9, insignifigant IMO) which means longer tire life and reduced rpm/mph - both good things. The 1/2" reduction in tread width means less rolling resistance and reduced wind resistance, again, both good things. Negatives to this swap would be increased ride height (less than a quarter inch) and reduced traction available due to the narrower tread width but in reality, an ecomodder isn't likely to drive their car to the limits of traction anyway. Weights for this particular tire in both sizes is listed as the same but most others are lighter in 175, to the tune of 2 lbs or so less per tire.

Side note: the Defenders are Green X rated for LRR but weigh 19lbs. The Hankook OPTIMO H724 (first other tire I clicked on) weighs only 15 lbs. Would you rather have LRR or less weight?