I have a 1984 ,mercruiser 454/400 cyclone serial number 6668656 ,I'm looking for the cam specs and what valve springs We're used , I'm sending the heads out to be freshened up and was hoping someone could help me out .thanks in advance.chris

It's a Crane 132561 cam. Crane spring number is 99893-16. Springs are set up at 115/340 lbs.
Here's the specs
http://www.cranecams.com/product/car...detail&p=24005

Good engines. The only difference between those, and the "420HP" versions, was the 420's, had a Gil exhaust, holley double pumper, and single plane intake.

Pickles got you covered on the original crane cam they came with.

Thank you very much for the info ,info was a huge help