340 exhaust manifold questions

7duster4 said

Seems like a very good price. I have seen rusty sets at swap meets for $400. Is it really necessary to use the 90 degree filter adapter on the 318's? I plan on doing the hp manifold mod sometime down the road but sure hope I don't need the adapter to make it work.

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It depends on which year you get for the passenger side. The swept back units like I have (pictured above) require the 90* adapter. The later ones have a "center dump" manifold that doesn't require the adapter. The swept back units supposedly have better performance.

I've read the article listed above, and its very interesting. However, I think the results would change dramatically (especially regarding the headers) if they didn't use the stock Durango camshaft. In cars, most people are going to want to make peak power higher than 4500 RPM.