Crank pulley question..

[T16]

I´m going to buy a 2-groove crank pulley on ebay (for a ´69 383 with PS and without AC)
So far i´ve found two kinds of pulleys.. one with a slightly smaller diameter on the inner groove..

Any comments on this..? Dont know witch one to buy..

[firefighter3931]

The smaller groove (inside) will speed up the waterpump and alternator. Depends on the application as to whether or not that is a good thing....


Ron

[Chryco Psycho]

no the smaller pulley on the crank will slow down the water pump & alt
I have had problems with some crank pulleys grinding against the waterpump pulley with a mismatched set so the smaller pulley May help

[T16]

Found this site: http://www.440source.com/pulleyscrank.htm
So I think its the 3rd one i´ll be going for..

According to YearOne, SB and BB use the same pulley 
"2-groove crank pulley for 1970-1974 small-block, 1965-1974 big-block"

http://yearone.com/serverfiles/part.asp?pid=MJ102&c=1&e=0&cat=1&hid=113AF4928&trk=

[firefighter3931]

no the smaller pulley on the crank will slow down the water pump & alt
I have had problems with some crank pulleys grinding against the waterpump pulley with a mismatched set so the smaller pulley May help

  Chryco is correct ! I misread the question, sorry for the confusion. 



Ron