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Jimbo,
I know you have a 78 351W from your other post. Please give us the info required to make a reasonable estimate.
Eliminating the Cat is your real gain. Probably give you a ten HP gain. Dual exhaust vs. stock exhaust is your largest HP gain for the money.
My Way is the Highway
KingFisher
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
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