5.7L Vortec REVERSE rotation engine?

[Duramax]

I have a 1982 boat with twin 350 GM engines that I am looking to get replaced, preferrably with newer 5.7L Vortec Marine engines. I have received some conflicting information regarding weather there is such as thing as a TRUE Vortec (199-97 and later) 5.7L marine engine. Crusader and Sea Maxx sell reverse Vortec 5.7L engines whereas Indmar says GM does not sell an aftermarket REVERSE rotation 5.7L Vortec. Which is it? WHY do they charge an extra $1000 for the reverse rotation? Can I purchase one and easily make it a REVERSE rotation? help...

 

[Bondo]

Re: 5.7L Vortec REVERSE rotation engine?

The Major differences are, Timing gears, instead of a chain.... Different cam... Dist... <br />I can see the $1000. difference....

 

[a.d.mobile]

Re: 5.7L Vortec REVERSE rotation engine?

did some checking too you are on trac with sea maxx or crusader the gm engines are built one way only. the marinizer makes changes, as bondo said but they still use a timing chain and gears the reverse rotation happens with cam, which causes a different dist. this work is hand done which causes the extra$$$$$$. are you going vortec with injection? or carbing them?

 

[navigator336]

Re: 5.7L Vortec REVERSE rotation engine?

Reverse rotation often is less efficient (up to 25% power loss). It's better if you're repowering and can afford it to but in a reverse rotation drive that has the same gearing as your current boxes.