DK4200

I was doing a little comparing today with different tires sizes and the wieght of them... i have been running my 16" rims at the track with Kumho tires. I plan on running with my stock 14's at the track once i get my Azenis tires up front. Well today i decided to weigh and measure to compare the 14" to the 16" rims and tires. My 16's weighed 40.5 lbs and stood about 23.5 inches tall... my 14's weighed approx. 34lbs and stood about 23 1/4 inches tall. Now i know that loosing 6-7lbs per tire all the way around will make a difference but since Azenis only has 1 tire size for 14" rims (195-60-14) I was wondering if i could run 185-60-14 in the back for less surface area hittng the track. By having a smaller tire in back will this hurt my performance at all or should i just stick with 195's in back? TIA