Which manifold for 4.3 Vortec/OMC?

[jdtower23]

I have an '88 4.3 OMC...I am planning on buying a new GM 4.3 base Vortec motor....the Osco 1 piece manifold kit says everywhere NOT to use with Vortec motors....I don't know why....do i have any other manifold options?

Thanks

 

[Don S]

Re: Which manifold for 4.3 Vortec/OMC?

The 4.3L Vortec engines are really bad about sucking water back into the exhaust. Even worse than a V8 Vortec.
OMC and Volvo both used a 2 piece riser and manifold on the 94 and newer V6's (Not sure about earlier OMC) and in 94 Volvo and OMC went into the joint venture.
Anyway, they also have a special elbow that prevents water from sucking back into the engine. (Item 18 in the pic below)

 

[jdtower23]

Re: Which manifold for 4.3 Vortec/OMC?

Thanks Don, do you have a part # for that elbow?

Here is the kit from OSCO that's supposed to be a replacement for the OMC 1 piece manifolds...

http://www.boatbandit.com/osco-omc-exhaust-manifold-kit-5859.aspx

Could the setup you have pictured be made to work in place of these?

Thanks

 

[Don S]

Re: Which manifold for 4.3 Vortec/OMC?

http://www.volvopentastore.com/EXHA....342381--view_id.312620--search_type.category