ID this exhaust manifold
October 28th, 2018, 01:10 PM
#1
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Location: Leominster, Massachusetts
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ID this exhaust manifold
Can anyone tell me what engine/car originally used these exhaust manifolds? They were on the 455 I bought in 1999 to put in my 1979 Hurst/Olds. I replaced them with a pair of W and Z manifolds since I didn't want to use headers at the time. I threw these in a box and they've been there ever since then. Any ideas? The first is an X manifold 406301 with a date of 8. The second is a T manifold 398708 with a date of 351.
October 29th, 2018, 08:53 AM
#4
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Location: Northern VA
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406301 is a LH manifold from a 1971-72 Olds full size with a 455. 398708 is a 1968 BBO RH manifold. Neither of these is internally divided like the W/Z manifolds and thus will not flow as well. They were not paired up on an engine from the factory, either.
October 29th, 2018, 04:12 PM
#5
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Thanks.
The 406301 LH manifold makes sense since the motor came out of a 1971 Delta 88. Guessing the owner of the car/engine before me changed the RH for some unknown reason.
The 406301 LH manifold makes sense since the motor came out of a 1971 Delta 88. Guessing the owner of the car/engine before me changed the RH for some unknown reason.
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