Here's a little matrix I made balancing tire size, white wall size and price. These are from the Summit catalog.
I ended up going with the P215, which was a little smaller than I wanted but went with those due to price.
K
EDIT: I see you were asking about 15"; these are 14".
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'63 LeMans Convertible
'63 Grand Prix
'65 GTO - original, unrestored, Dad was original owner, 5000 original mile Royal Pontiac factory racer
'74 Chevelle - original owner, 9.56 @ 139 mph best
http://www.superchevy.com/features/s...hevy-chevelle/
My Pontiac Story: http://forums.maxperformanceinc.com/...d.php?t=560524
"Intro from an old Assembly Plant Guy":http://67-72chevytrucks.com/vboard/s...d.php?t=342926