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OEM v8 Manifolds

Old 06-16-2018, 09:34 AM
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Default OEM v8 Manifolds

I'm assembling an AJ27 s/c engine for a project car I have, and I'm forced to ditch the original manifolds because of clearance issues around the framerails.

I also have a set from an AJ33 4.2 n/a which fit physically, but I would like to confirm that I won't loose any power using these manifolds.

It would seem as though the branched design indicates some degree of tuning in them, but of course I have no way to verify this in a home environment and the outlet flange does look somewhat "tighter."

Old 06-17-2018, 11:47 AM
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If being mounted onto a Supercharged engine- you WILL lose power using the NA split logs from the AJ33/34/36.

The 'split logs' are designed to boost low speed torque on the NA engine by keeping the exhaust pulses separated. On the S/C AJ33 when we kept the 'split logs' we lost power as outright flow capacity was more important than split the tuning pulses and the AJ33 S/C manifolds are already of a smaller cross sectional diameter than the AJ27 S/C.

Can you source AJ33 SC manifolds and will they still fit in your application?
The following 2 users liked this post by Count Iblis:
deuce2000 (07-04-2018), Panthro (06-29-2018)
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