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Old May 17th, 2017, 04:31 AM
1972RedNeck 1972RedNeck is offline
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Default Re: Magnum Exhaust Manifolds

Quote:
Originally Posted by bigblockv6 View Post
Why is because the small head ports are not machined to accept the larger port manifolds. Physically they may bolt up but the surface will be uneven. Like I mentioned using the 351C,379 non Magnum 401 & 478 I Beam manifolds will work, they are the same free flowing design as the Magnum manifolds other than the ports at the mating surface are smaller which is just fine.
So the head ports will be centered in the manifold ports, it's just that the head ports are smaller than the manifold ports? Will that actually negatively affect performance at all?
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