Mercury Racing 520 info???
 

Looking for some general info on this motor...Google search world is pretty limited

Does the 520 need refreshed at a certain hours? Like the 525
Can the motor be used to build more HP/Upgrades I know CMI makes headers for this application?
Anything good or bad about the motor?

Thanks in advance!!

Page 46 - Maintenance.
http://download.brunswick-marine.com...8m0087090r.pdf

The 520, 540, 565 all use the same cam as was used in the 525efi.

I like the recommendation every 100hrs or yearly to compression check cylinders.