496 mag to 496 mag HO conversion
 

I know the only differnce is the ecm program and camshaft.

has anybody done it? worth it?
for less then 2k I could add 100hp to my twin engine boat and go from 75mph gps to 81 mph gps.

I like to hear back from someone that has done it

thanks

I have the cam and ecu if you want to do it. PM me. Both are brand new

I don't think I would mess with just a cam. I would go ahead a Raylar it up and you will be more happy. My thinking is you won't be happy with a 100 hp, it will make you want more.
http://www.raylarengine.com/packages.html

how much for the cam and ecu?

do a search raylar has a kit , more aggressive cam and ecu reprog. that will bring you up to 460hp instead of 425hp.

A gain of 50hp to each engine will not get you a 6 mph gain. More like 2-4 mph.
You should gain about 300rpms.

all that work on twins for 2 mph gain will suck,but if I gain 4mph it would be ok,well I will be doing the cam and ecu switch Saturday,then will have to wait for the 1st nice weekend to see if it was worth it or not.

Throttle body has some mod also I recall...

Just plug all your numbers into the propslip calculator and then increase the rpm by 300 and see what you get. That should be pretty close.
http://go-fast.com/Prop_Slip_Calculator.htm

Problem is that it's a ton of work for very little gain.
You'll need parts obviously.

Even the balancer has to come off. Lot of work but hey I remember all that.