I need to order a cam for my shortblock ASAP and im really thinking about just going with the crane cam 132561 which is the stock mercruiser 420 camshaft.

Specs right now are:

Holley 800
gm forged crank
gm forged rods
gm forged pistons
mark v 454 block stock bore
420 intake manifold
stainless marine exhaust full length risers to transom
Heads are up in the air but possibly 188 rect ports w/ maybe port work
compression ratio is looking like 9.25ish with 118cc chamber heads


If anyone has any experience with camshafts on a setup like this i would appreciate some input, from what i have read i think my best bet is probably that 420 cam or possibly something with a little less lobe seperation but i DO NOT want to have to worry about reversion

Just call Bob Madea of Marine Kinetics...

i dont like to call someone if i have no intention of buying something from him

I emailed him a few weeks ago, got no response

What he charges for custom cams is cheap and worth every penny.
Also go to a roller cam, flat tappet are a thing of the past.
Just my 2 cents

From what I understand, it costs about $1500.00 more to convert a Flat Tappet to Roller Cam than it does an 88 and newer Roller Ready Block. Any truth to this in Marine Engines as opposed to Hot Rod Small Blocks??

About $1,200 for any block, lifters, cam and springs. Moral lifters, good springs, custom cam.
Call Bob!