Adding cats to LT headers - need some expert input.

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?

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).

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.

swathdiver said:

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.

Click to expand...

Yeah, I'm not trying to spend $2000+ dollars worth of exhaust on a car that's worth maybe 8-10k.

I do have a welder friend with a shop to lift the car up, so that's a plus, vs. my normal rolling around on a gravel driveway.

Charlie207 said:

Yeah, I'm not trying to spend $2000+ dollars worth of exhaust on a car that's worth maybe 8-10k.

I do have a welder friend with a shop to lift the car up, so that's a plus, vs. my normal rolling around on a gravel driveway.

Click to expand...

It may only have a market value of $8-10K but how much would it cost to replace it?

I'm slowly getting mine ready for more power, going to spend a pretty penny on a 3.5" Y-Pipe and exhaust system, about $3.5k.

How long will those headers last compared with Kooks for example? If they'll last longer than you plan to keep your truck then it makes sense.