i have 2 -10 bolt rearend first one has a gm 44 12234485n 15-41 gears second one is a gm 80 11-31 gears can anyone tell me what the best for my 1970 ss - 454 with 350 turbo tranny any info will help thanks

31-11? never heard of that ratio... Neither of these is a great choice. unless you miss-counted on that 11-31. The 15-41 is a 2.73 ratio. A good all around ratio for your combo would be somewhere around 3.23 to 3.42

take a look here...
http://www.chevellestuff.com/generic/axlecodes.htm#1966

david

this i found today number on rearend is GM53 con1 c269 spool has gm 80 nf 387 3439 3678439 pinion 3790628 11:37 G13-36 any info will help greatly thankd roy