I am planning to put a 4 barrell on my 70 SX and have found a 455 manifold though it has a EGR valve on it. What years have this valve on it? Anything to keep a eye out for?

Thanks

 

EGR was federally required starting with the 1973 model year, though I think some California cars got it in 1972.

 

I had an Offenhauser manifold on my '70 SX many moons ago. I don't even know if they are still around anymore, I never see their name. I would stay away from an EGR manifold, if only for asthetic reasons. I see stock 4bbl manifolds on Ebay from time to time. They usually go fairly high. Then there's always Edelbrock. Hope you find something decent. Chumley

 

http://www.exeterautosupply.com/Docs...%20catalog.pdf

Norm

 

If an EGR manifold is all you have then go ahead and use it. You can always buy an EGR block off plate. You can either paint it to match the manifold or leave it chrome plated. The benefit you get by changing to a 4 barrel carburetor will far outweigh going to an EGR manifold as opposed to staying with a 2 barrel carburetor.

 

Where can you get an EGR valve block off plate?Chumley

 

Just make it out of steel and drill some holes.

 

You can use a fuel block off plate as an egr block off.
http://www.mmsacc-stainless.com/html/engine_access.htm