question about underdrive pullys...

[Pex]

Got my blue aluminium steeda underdrive pullys to my 94 (5.0l) today.

I immediatlly noticed that the crank-pully I've got is flat but the one on my motor is ribbed.
Have I got wrong parts or am I totally out of my mind here ?

kind regards
Peter
p.s excuse my bad english but I'm from sweden so..

 

[94gts]

you type better english than i do and thats all i speak

anyway, i have never seen a crank pulley without ribs. Are you looking at the right pulley? With the underdrives the water pump is the big one and the crank is the smaller one (which should have ribs).

 

[Pex]

You pointed me in the right direction.
The pully on the water-pump has no ribs.
I took for granted that the biggest pully should be on the crank...
Thanks for your reply.

Kind regards
Peter