Well I am closer to getting the engine assembled; I would like to get this manifold from GM part #12496820. According the GM Performance parts this manifold will work with vortec heads P/N 12529093, 12558060, 12497186 or 12464298. I have the 062 heads. Looking for a dual plane vortec manifold that is egr equipped. Looking for suggestion.

 

Any of the performer vortec intakes with an adapter plate should work fine. A good buddy of mine runs that on his vortec 305 TBI. Can I assume that is the engine we are dealing with here?

 

186? Isn't that the old '69 Z-28 head?

 

I have a balanced 350 bored .040. The only thing holding me back, now that I have the $$$, is vortec manifold with egr provision, rockers and pushrod.

 

Care to explain how the EGR setup is going to work? Those intakes listed are specific for a reason: the heads listed have the cast in exhaust crossovers. 906/062 castings do not. They require external EGR setups.

 

If he has the GM vortec TBI intake he can use EGR by plumbing into the header. CHP did this on their vortec TBI set-up and it was fairly slick how they did it.

 

Could probably do it the same way GM did on the Corvette, couldn't he? I know the C4 vettes had external EGR setups.

 

Yes, but he's in Cali. Cali being the smog police they are, I believe requires the OEM setup. An external EGR is not OEM.

I don't know if southern California is any different, though.

 

My car is registered in Michigan but still prefer to have the EGR manifold. If anyone can give me a part # for a such a set up and dual plane, your help would be appreicated. I am already looking at SDPC fort heir TPI version of the EGR plumbing.

 

Any of the part numbers you list should work. There's no such thing as a raised-runner-moreso-than-the-already-raised-runners or anything crazy like that. It's just a matter of, like I said above, the cast cross overs.

 

Does anyone have a dimension drawing
of GM 12496820?
I am interested in the height of,
block, to carb flange.