If you want to keep the Y-pipe look, for one from an earlier slip on cat truck, 88-92 I think. They have larger primary tubes, with 3'' collector. Even better than that are the 96-up 3/4-1 ton trucks with large dual pipes back to the muffler, that's what i'm using. The TBI truck manifolds are much better than the cars or even the Vortec trucks.
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