[kieth]

Originally Posted by bigblockv6

There definitely something wrong with your figures. Though it's been a quite sometime I do remember my 68 K2500 with 4.56 and stock 33 inch tire would run somewhere between 2200 to 2500 rpms at 55mph.

here is a spreadsheet with 32" tire diameter:

http://6066gmcclub.com/forum/attachm...6&d=1394467957


I will run one for 33's and post it later today.....Kieth