Offshoreonly.com - 454 Magnum, Cam, Intake, Carb.

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- - 454 Magnum, Cam, Intake, Carb. (https://www.offshoreonly.com/forums/general-q/240098-454-magnum-cam-intake-carb.html)

No need to remove the y-pipe. Just cap the ends with Fernco caps from Home depot/lowes and clamps. That way a future owner can go back to silent choice without having to pull the motor. Silent choice is an expensive option and it adds value to your boat. You actually get more flow with it installed since when in open mode exhaust is exiting through the transom and the y-pipe.

Quote:

Originally Posted by redstinger (Post 3223916)

Don't you think that the exhaust flowing out of the "Y" pipe would cause the water that the prop is trying to bite into to be disturbed? Just askin not sure.

Want to re-open this thread. Leaving the bottom end stock on my 454 Mag, what is the most HP I could get out of this motor and what would I have to do?

"what is the most HP I could get out of this motor and what would I have to do?"

550ish...Boost.
http://cgi.ebay.com/ebaymotors/Weian...item1e5ef0cd09

Quote:

Originally Posted by Back4More (Post 3235794)

"what is the most HP I could get out of this motor and what would I have to do?"

550ish...Boost.
http://cgi.ebay.com/ebaymotors/Weian...item1e5ef0cd09

Hahahaha!!!!! Good one!!!! Want to stay N/A.

Have to go with Griff then...

Quote:

Originally Posted by scottw (Post 3223901)

Thanks for all the great info everyone. Griff can you recommend some parts to go with, to set-up this application? What cam, intake, carb size. I guess for the other parts, whoever I buy the cam from will match me up. Also found out that the stock cam is .224 Duration/ .300 lift. I quess you know too that it has rectangular port heads on this motor. As for the exhaust, it doesn't have the stainless risers that dump water at the tips. I guess I have to watch for water reversion with the duration of the cam. Thanks again.:drink:

Call rmbuilder and he will set you a good cam choice and all the parts to go with it. You will need longer risers in order to use a bigger cam and gain anything significant.

I would use an Edlebrock Air Gap intake and a Holley 800 carb.

The stock flat tappet cam in your engine now is .510/.510, 224/224 on a 115.5 lobe sep

Imco risers for sale in this thread at a good price. Not sure if they are the longer ones, but worth checking out.
http://www.offshoreonly.com/forums/s...ne-marine.html