Does (block)Size really matter?

I have a process that sends data through a dblink to an intermediate database and then on to another database. The first database is blocked at 4096, the second is at 8192, the third at 8192. Response is slow (5000 rows in 1.5 hours. Could the difference in block size be a factor?

Thanks!
Ron

Important Notice!!
If you are not the intended recipient of this e-mail message, any use, = distribution or copying of the message is prohibited. Please let me know immediately by return e-mail if you have received = this message by mistake, then delete the e-mail message. Thank you.

--
http://www.freelists.org/webpage/oracle-l