Tires, how much leeway on a certain wheel?

I've a need for snow tires. Currently, the tires are 235/75R15. Traction would be improved with slightly smaller tires, but I am not sure as to how much smaller I can go with the rims on the car (15 X 6JK). I found a good deal on 215's, would this work??

Thank you,

Cosmo

 

Coker has a chart on their site showing tire and wheel size that I find handy...d32

 

why would traction be improved with smaller tires?

 

They will fit the rim fine; probably about an inch and a half shorter.

 

WWW.TIRERACK.COM

Nifty website!

 

Thank you all. Ordered from Tire rack, but info from them on old cars is spotty at best.

Narrow tires put more weight per sq in of footprint, enhancing traction.

Couldn't find the wheel/tire chart on Coker. Plus I know recommended on these rims IS LR78/15, or 235/75R15, yet budget needs help, and 215 tires are nearly half, so the question presents itself.

Cosmo