Originally Posted by
halljam70
I've got a performer EGR intake I was thinking of putting on the truck (replace the factory TBI intake), and the reason is sitting on top of the intake. Before that, I need to rethink the exhaust system. Current over the plug manifolds have AIR blocked. Makes it a pain when I SMOG test. They flow into a factory y-pipe, 2.5" outlet, 2.5" cat to a flowmaster muffler. I wanted to do headers dual cats, true duals, but that won't be legal here in Nevada (talked it over with Ref station. Can't stand the visual requirement, if it is under the limit, its under the limit, shouldn't matter what it looks like under the hood). Now I'm thinking of going with stock 1990 suburban under the plug manifolds. Factory y-pipe (3" outlet), back to an aftermarket 3" cat then a single in/dual out muffler. Not sure it will help performance but it would eliminate my two biggest issues left. 1, removes all evidence of the AIR system so the truck will pass as a later model motor swap. 2, eliminate burned plug wires.