Cats and headers options

[Chris253]

I just ordered a super 44 exhaust system minus the cats, for my 97 k1500 and was curious, what would you add to this combo? I'm trying to get this thing to breathe a bit better before I drop in an engine I just got done building. It's a vortec 355, should make around 400hp after the tune. But now it needs cats and headers at least but I'm no exhaust expert at all so I'm a little lost. I've read about install complications and this is all going to be installed at a shop so I'm trying to avoid the surprises so to speak.

 

[Chris253]

And do I need a y-pipe or hpipe? Or will the oem work?

 

[TKerr]

That is kind of a broad question, but I will answer it as to how I would do it for where I live.
First anything pushing 400+ horsepower I typically run 1 7/8" equal length long tube headers with 3" collectors. Also I don't eliminate cats but use high flow cats (emissions and safety inspections).

Option 1: If funds allow I use a full Borla stainless mandrel exhaust system with ceramic coated headers. But this is not cheap.

Option 2: a good set of headers (do not skimp here; you will regret later), copper header gaskets, locking header bolts. 3" stainless blend heavy gauge exhaust pipe. True dual with a cross over pipe.

Again this is just my opinion and how I would do it

 

[dsk07]

Well, some good tips, but really, locking header bolts, coated headers, did he ask for a dream system of unrealistic parts, or, some help with a realistic system......I guess I didn't read either!

 

[big_mike]

My exhaust setup is as follows, still a build in progress not running yet. It's a 1999 Tahoe 4x4.

Summit shorties ($200)
Thunderbolt 2.5" hi-flow cats ($100 set)
Thrush Welded 2.5" dual in/dual out muffler ($40)
Full 2.5" mandrel bent pipes from the headers out the back with cats, O2 bungs and muffler all welded ($350)

Should be a great improvement over the tiny stock exhaust that chokes the power outta these trucks. I went with shorties for ease of install and no fitment issues with the 4x4 parts. If it was a 2wd truck I'd most definetly go with the TBI longtubes to save money, have the missing O2 bung welded into the collector, delete the EGR and your good. There is a good thread on here for the TBI longtubes on a Vortec truck.

 

[97Layzboy]

Quick question on the missing 02 sensor. Can an exhaust shop weld that bung into the collector or is that something i have to do? i ask because my exhaust shop that did my exhaust would not install the headers. I seem to be having stuttering issues and the tuner from Black Bear told me i need the one 02 sensor on each side of the engine on the headers and then tuning the PCM should hopefully help my issue.

My exhaust setup is as follows, still a build in progress not running yet. It's a 1999 Tahoe 4x4.

Summit shorties ($200)
Thunderbolt 2.5" hi-flow cats ($100 set)
Thrush Welded 2.5" dual in/dual out muffler ($40)
Full 2.5" mandrel bent pipes from the headers out the back with cats, O2 bungs and muffler all welded ($350)

Should be a great improvement over the tiny stock exhaust that chokes the power outta these trucks. I went with shorties for ease of install and no fitment issues with the 4x4 parts. If it was a 2wd truck I'd most definetly go with the TBI longtubes to save money, have the missing O2 bung welded into the collector, delete the EGR and your good. There is a good thread on here for the TBI longtubes on a Vortec truck.

 

[97Layzboy]

Quick question on the missing 02 sensor. Can an exhaust shop weld that bung into the collector or is that something i have to do? i ask because my exhaust shop that did my exhaust would not install the headers. I seem to be having stuttering issues and the tuner from Black Bear told me i need the one 02 sensor on each side of the engine on the headers and then tuning the PCM should hopefully help my issue.

My exhaust setup is as follows, still a build in progress not running yet. It's a 1999 Tahoe 4x4.

Summit shorties ($200)
Thunderbolt 2.5" hi-flow cats ($100 set)
Thrush Welded 2.5" dual in/dual out muffler ($40)
Full 2.5" mandrel bent pipes from the headers out the back with cats, O2 bungs and muffler all welded ($350)

Should be a great improvement over the tiny stock exhaust that chokes the power outta these trucks. I went with shorties for ease of install and no fitment issues with the 4x4 parts. If it was a 2wd truck I'd most definetly go with the TBI longtubes to save money, have the missing O2 bung welded into the collector, delete the EGR and your good. There is a good thread on here for the TBI longtubes on a Vortec truck.

 

[97Layzboy]

sorry for the double post. When i hit post reply it came up with a server issue error.

 

[big_mike]

Quick question on the missing 02 sensor. Can an exhaust shop weld that bung into the collector or is that something i have to do? i ask because my exhaust shop that did my exhaust would not install the headers. I seem to be having stuttering issues and the tuner from Black Bear told me i need the one 02 sensor on each side of the engine on the headers and then tuning the PCM should hopefully help my issue.

Yea, exhaust shop should be able to do it but you'll need it either towed there after the header install or have it welded into the collector prior to your install. The front 2 oxygen sensors effect the air/fuel ratio so you don't want to drive it around with only one or none hooked up. The rears are emissions only post cat sensors.

 

[toomanyhobbies]

I am really happy with my SS ebay headers from Taiwan that were $80. They are mid length. I had a full mandrel bent 2.75" SS exhaust made with provisions for the forward 02 sensors and a 2 in 2 out magnaflow XL installed. Sounds good it is not quiet.

On a 2 door where there is less room I think it makes sense to go 2 in/out rather than 2 mufflers and a cross over.

This whole thing cost around $1300 with the headers.

One of your questions was not answered which is when you get into headers you can throw the factory Y pipe in the trash it is of no use.