Califorinia Emissions Equipped, Header choices - help!

[99'Subourbon]

Hey Everyone,

Been awhile since I posted, but getting ready to do another round of upgrades to my 'burb. I am throwing 2 code for the far driver side bank and far passenger side bank 02 sensors. So in addition to 'fixing' my cats, I am going to do a full exhaust setup.

That said, my burb is from california, leaving me with an unfortunate problem to solve for; long tubes, and the egr, and air connections for the emissions control. Now I don't need to have long tubes, i'll go with whatever tubes net me the best performance for what I am looking for, which s as little loss as I can get on the low end, while providing some more umph in the 55-65 mpg range (running 33's on 3.73s). My burb isn't a racer, and I don't expect it to be, but I live in the White Mountains in AZ, and we have lots of hills, and these trucks aren't light.

So with that info, can anyone point me in the direction of best setup? And give me a link to some headers that will best fit my needs, and are as cheap as possible? I don't need to run cats, unless the back pressure will help (we don't have emissions here) and I do plan on ordering a tune. Also, we don't have rusting problems in these parts, so I am not concerned with extra protective finishes.

If there is any other info I can provide to help, let me know.

 

[df2x4]

Does anyone even make longtubes for the Vortec motors? I've never seen them, but if they exist I'd like to know about it. I'm going to be upgrading my Suburban's exhaust eventually, too.

EDIT - Summit has these shortys with AIR fittings for $230, cheapest set I can find. I run painted Pacesetters on my truck and have been very happy with them. Had to cut a little bit out of the flange to cure a fitment issue but they've held up just fine. (This was also on a V6 so you probably won't have a problem.) Just don't expect them to stay black, all the paint flaked off of mine in about a week.

http://www.summitracing.com/parts/psm-70-1332

I think whatever you go with is pretty much personal preference, the only variable I can see is whether you have the single or dual inlet muffler. Although if you're replacing the entire system then you can just set it up however you like, or go true duals. FWIW I run an OEM replacement style Magnaflow Y-pipe with cat, and a Gibson cat-back kit. I can recommend both, sounds nice but not overpowering, especially for a V6.

 

[99'Subourbon]

I would hope they make headers that fit our trucks. Is there any actual difference to the layout pre and post vortec?

Edit: Just did some digging around - no difference in TBI and Vortec headers, outside of EGR and 02 sensor placement. Being you can get long tubes for a TBI 350 for $150~, and $300+ for vortec, it'd be cheaper to buy TBI LTs and have a shop weld up the 02. Now to find out what the air fitting is for california equipped vehicles.

That said, single is cheaper than duals, correct? Should the pipe diameter be 2.5 or 3" for a single setup?
Still don't know what my setup should be - trying to avoid any performance loss.

 

[df2x4]

Found this, there's some good info in here.

http://www.gmt400.com/forum/showthread.php?5826-Headers-on-the-5-7-Vortec

EDIT - Looks like the major longtube issues are going to be keeping your EGR and AIR intact. Can't really find any examples of anyone doing either. I'm not really familiar with California's emissions laws, are you not legally able to just tune those things out of the PCM? For a single setup I'd go 3", dual no more than 2.5". Single will definitely be cheaper.

EDIT AGAIN - Sorry I misread that, I thought you were actually located in CA, hence the desire to make the AIR/EGR setups work. If you really want to run longtubes I'd just pull/block off your AIR and EGR parts and have them tuned out. Then all you have to worry about is the O2 bungs.

 

[99'Subourbon]

Yeah, not in California (who would want to live there?)

I don't need long tubes, I just want whatever is gonna be the best performance with as little net loss in the low end as possible, after my tune.

I read deleting the air setup is a pita.

 

[df2x4]

Not sure I can help you much there. The only way I can think of that you'd ever lose low end power with an exhaust upgrade is if you create a situation with too little backpressure, running giant diameter pipes or headers with huge primaries on a stock motor. As long as you keep it within reason I think you'll be fine. I've never seen one of the air setups in person so I have no idea what all is involved in removing it, but if it's not something you want to do then shorties might be the only real option from what I can tell.

 

[99'Subourbon]

Thanks for your help. I'll call the local exhaust shop and see if he knows about it.

Chances are I'll remove it if it isn't anything major.

 

[99'Subourbon]

Read some Sanderson headers and Doug thorlry blog posts, as well as a very informative post over on camaroz28. Seems shorties are just as good, with a full exhaust setup, if not better than LTs, in most truck applications where useable power is the focus.

Hotrodding magazine did a test of 4 different headers for a 383 crate motor, and the smallest, shortest headers showed the best useable gains.

Guess I'll be looking at shorties.

 

[96Z71ECSB]

Shorties are part of my plan too, but I have to keep all the emissions intact (EGR, cats, don't have air injection).
Colorado tests every two years, so I may try to locate a used cat/head pipe assembly, remove the cats (pipe them), install "dummy" rear O2 sensors, and run that assembly in between tests.
I'll just bolt on my original cat/head pipes/O2 sensors when it's time to test.

In your case, you don't have to deal with emissions testing. I would take the steps to get rid of it all.

 

[99'Subourbon]

Does anyone even make longtubes for the Vortec motors? I've never seen them, but if they exist I'd like to know about it. I'm going to be upgrading my Suburban's exhaust eventually, too.

EDIT - Summit has these shortys with AIR fittings for $230, cheapest set I can find. I run painted Pacesetters on my truck and have been very happy with them. Had to cut a little bit out of the flange to cure a fitment issue but they've held up just fine. (This was also on a V6 so you probably won't have a problem.) Just don't expect them to stay black, all the paint flaked off of mine in about a week.

http://www.summitracing.com/parts/psm-70-1332

I think whatever you go with is pretty much personal preference, the only variable I can see is whether you have the single or dual inlet muffler. Although if you're replacing the entire system then you can just set it up however you like, or go true duals. FWIW I run an OEM replacement style Magnaflow Y-pipe with cat, and a Gibson cat-back kit. I can recommend both, sounds nice but not overpowering, especially for a V6.

Can you provide me a link to the magna flow y pipe, or a something similar to run with shorty headers?

Thanks,