Adding cats to LT headers - need some expert input.

[Charlie207]

I'm close to buying the Speed Engineering LT headers & Y-pipe kit, and want to add catalytic converts to pass emissions, and not stink.

Headers & Y-pipe kit: https://speed-engineering.com/colle...erado-sierra-1-3-4-longtube-headers-2007-2013

There's not a ton of info (as far as I've seen in the last 24 hours of sort-of searching) on the best way to splice in cats., so I figured I'd ask here for how you guys have done it.

I've read that there is a minimum distance from the end of the collector to the face of the cat. substrate, to allow for effective exhaust scavenging. That doesn't seem to leave a ton of room on the driver's side for adding a cat. I see there is a drop-in set of headers w/cats from Stainless Works, but that is too rich for my blood. Their design does offer a basic template to go off of, though.

So far, these are the shortest OBD2-compliant cats. w/O2 bung that I've seen: https://performance-curve.com/3-catalytic-converter-o2-high-flow-for-late-models-federal-emissions/

Thoughts?

 

[Joseph Garcia]

If it were me, I'd take the truck to a local exhaust shop and let them tell you how to best perform the work (and, I'd let them do the work).

 

[swathdiver]

If I were adding long tube headers to mine, I would also purchase a catted Y-pipe from that manufacturer. They've already figured all that stuff out and use performance catalysts.

I see why now, that's a huge difference in price compared to Kooks, American Racing, etc.