[mwebb]

did you calculate in a fudge factor to allow for the difference in OD when making the FE comparison between the
155x80x13 versus 195x50x15 tire wheel combination ?

are you thinking the change in 1/4 mile times are a direct result of
increased mass of the wheel tire assembly
or
increased aero drag of the wider tires / wheels
or
change in final drive ratio due to larger OD of the 15" wheel / tire ?

i have the same car and of yet un installed 15" alloy acura legend wheels with 195 60 15 tires

Originally Posted by ATaylorRacing

I'd suggest going to some 155x80x13 tires on American Racing Estrella rims. I went from that size 13 to the 195x50x15 tire/rim package on my Geo Metro 3 banger and the tire/rim pacage is 8 lbs heavier per corner. The old tires had a max tire pressure of 35 while the new ones would take 51.

In the end the gas mileage on flat ground/highway speeds remained the same due to much less rolling resistance, BUT the 1/4 mile times went from 19.9s normally to 20.6s.

When the weather gets warmer I will return to the 13 set up. The Power Star 13" tires are 14 lbs while my Estrellas in 15" are 18 lbs. My 15 inch rims are 16 lbs while the Am Racing 13s are 12.8...BUT, the newer 13s can take more tire pressure than my old ones. Going back to my 1/4 mile ets, I did take an extra 32 lbs out of the car to make the wt the same as it was earlier with the 13s. When I go back to the 13s I will loose anoth 32 lbs so that my new wt will be 1598 compared to the present 1630. I have taken 132 lbs out of it, but added 32.

Another idea I was thinking about was to keep my 15s, but go to the 175x55x15 size that are 4 lbs lighter and less costly than a new tire AND rim set up!