I am seriously considering adding long-tube headers and X-pipe. Seems cheap for this setup from Ebay. But I don't have much to spend. I don't have thousnads of $$$ laying around like some of you. Slowly I intend to modify my exhaust, intake, and possibly cam WAY down the road. IT'S A DAILY DRIVER.

Questions:
1. Would I need O2 connector extensions?
2. Would it need to be "tuned" after removing the cats? (Will the O2 sensors have an erroneous reading without cats?)
3. Any modification required to match this to the pipes running to the axles? I have a welder and can get adapters if necessary.

Thanks in advance.

 

Cant answer about this setup but yes you will need extensions for the 02 sensors, Yes to being tuned, you'll most likely get CEL in a short time after install, Don't know if they will match up but make sure they are the same size in Diameter. My Kooks came with EVERYTHING NEEDED to do the install. I don't see any clamps on your photos, also came with a little bracket to move the trans lines out of the way. So sometimes it pays to buy the better items for that reason. Also why no cats ???
Good Luck
NSF

 

First off, under stand how headers savage more exhaust out of the heads to increase horse power.



Next on headers, take a look how the X pipe is going to hook up to the header ends. The slip fit type connectors tend to leak, the bolt on type tend to end up with the bolts loose at some point, and about the best connectors that I have see are the old Pfadt header that used a C clamp instead.


Next lets cover High flow cats, and you only end up with about 4HP loss with them in play. So without High flow cats, the car cabin stinks of un-burnt fuel every light, so run with High flow cats. Also, by watching the video above, you will understand that the High flow cats need to be mount at least 4"s or more from the end of the header collect itself (collect inside the pipe, and not the end of the headers pipe isntead).

As for O2 sensors, the car only uses the pre cat sensors for the tune. The rear O2 sensor are just monitoring the effectiveness of the cats alone. So with the cats moved farther away from the heads, and them not as effective as the OEM cats, even if you did leave the rear O2 sensor in play, would still end up with codes since the differential reading of pre and post o2 sensor would not be great enough. So with headers, rear O2 sensors are deleted, the socket ports on the W pipe plugged with thread plugs, and Rear O2 sensors are tuned off when the car is tuned.

If your not going to tune the car right way, then anti foulers are used to pull the rear O2 sensor out of the exhaust stream, so they are reading less to prevent the codes instead.


So the break down with headers, since they will be More effective scavenging the exhaust gases out off the head (how heads make more power), the motor ends up running too lean. At less than WOT, the car is running is closed loop and will mostly adjust for the lean condition. In WOT, the car is running in open loop (not using the pre O2 sensor to adjust the tune) and running on tune tables alone.

So with headers, really need to get the car tuned so it's AFR are correct, and will produce all the power is can.
During the tune, the Rear 02 sensors are tuned off as well.


As for good deal for headers, that would be the OBX kits that come with high flow cats to start with. The cheap bolt and nuts, and manifold gaskets that come with the kit, throw them away and replace them with better nuts and bolt. On the exhaust manifold gaskets, just reuse the old OEM units still on the car.

Once you have the headers installed, dry fit the X pipe with high flow cats sections together connected to the muffler pipes as well, use the clamps to secure the pieces in place temperary, then spot weld the X pipe sections so you can drop the X pipe from the car to weld all the X pipe sections together.

Hence the OBX header kit with high flow cats comes with the 4 Band clamps for the X pipe after the cats/before the muffler pipes, and it's these connections once the X pipe has been fitted to the car, that we want to weld instead of using the band clamps (so you don't have an exhaust leak at them isntead). As for the rear muffler to X pipe connection, use the factory clamps.


If your check around, can get the OBX header kit with high flow cats and X pipe for under $900. As for the X pipe O2 flanges, just plug them with threaded plugs since your not going to be using the post cat 02 sensors after the tune.
Lastly, you will need front 02 sensor extensions cables since the sensor are being moved farther down on the headers, and don't forget to install a heat sheild on the starter solenoid so your not cooking if from the header heat. Also, make sure to move any hoses and wire lines well away from the headers so your not melting them.
To add, not a bad idea to ceramic coat the headers before you install them, so the radiate less heat as well.

https://www.speedwaymotors.com/Alumi...ters,5745.html

Here are the front O2 extension cables.

 

For me they are additional components that can give problems - for example clogging and 2 extra joints to connect. There is no way I would run cats if I didn't need to. Last year, in Washington state I had a car pass an emission test with cats removed.

So much information - THANK YOU.
I don't understand the connection between the bad smell while running no cats. Isn't the whole exhaust system sealed if connections are good and not leaking?
Yes - the starter heat shield. A couple decades ago I cooked a starter solenoid with headers and learned my lesson. Interesting flash back to the past for me.

 

I was literally about to pull the trigger on these same set of heads/mids and then I thought to myself.. I remembered all those times back when I bought 'cheaper' stuff - stuff that really depended on clearances and good, solid fitment, peace of mind. I held off and i'm so glad I did. While it may be worth it to you now, in the long run, seriously save up a little more and get a better brand that you know will fit - that comes with everything you need for a smooth, pain free installation. I've seen kits that come with every bolt, clamp, gasket, extension you need and it's just so nice when things fit perfect and you know they're built to last. I'd constantly be worrying about rust/rattles if i had got that. I also would be kind of embarassed when asked what it was - i'd rather say it was a (insert reputable name brand here) so people knew i used good stuff on my ride. Do what you want though, i'm just feeding you gibberish it took me years to learn. My dad always told me 'you get what you pay for'

 

The old saying applies here " You get what you pay for" ... save your money until you can buy a quality set of headers & an X pipe w/cats. I would suggest Kooks or American Racing Headers. The Kooks brand headers come with O2 extensions, quality hardware, and complete instructions to get your parts bolted on. Yes, you will need a tune after the install of any headers. Headers are a good mod for LS3 engines

 

I bought a set of Texas Speed 1 7/8 headers and 3 inch catless x pipe for 762 shipped to my door and I have had no complaints. Some people complain about rubbing issues but my 08 is not lowered and I have no issues rubbing what so ever. They sound great and came with everything I needed for a simple install. Be sure to get a tune afterwards tho!

 

Are they OBX headers? I have a pair on mine. You will need o2 extensions, you will need a tune, mine bolted on just fine.

 

Speed engineering are great and less than most other headers.

 

To add to my post, the only thing I can be very critical of when it comes to the ebay headers, after some months the passenger side headers shifted to right and was starting to make contact with the frame and was sounded awful, I actually thought it was my motor mounts going bad. I am sure it was due to inferior metal. So I shaved off 1/8 of an inch off the frame and the issue was resolved, painted the bare metal and it has been good ever since.

 

Personally, i would simply keep a close watch in the parts for sale section and find a good used set of AR or Kooks or something someone has removed from their car.

 

Something else to add to the mix...
I purchased a Diablosport inTune i3, and accomplished a standard 91 octane tune.
I just discovered that this tuner will not work with this modification. There is an option to custom tune my Diablosport to match the headers and O2 sensor modification. It would cost an additional $150.

I'll probably just keep it like it is for now. It's an awesome daily driver with nearly 450 HP. That's plenty for now. *sigh*

 

If you have an LS3 then just get Speed Engineering Headers
1. Yes, 02 extensions required, but you can add them as an option when ordering
2. Yes, tune required
3. Yes, exhaust mod required only if you have an 08 LS3, the 09+ will not require modification for Speed Engineering headers

 

I thought the rear O2s were deleted? Or are you referencing the front O2 sensors?

 

How about these? They are bolt-on and "claim" up to 15 HP gain. Not sure if further tuning would be required. I'd still like to get rid of my cats somehow.
Hooker Part # 70301303

 

I wont berate the ones on Ebay but there was a post, although I forget the member that had some of the less expensive headers on his car, he posted that the welds were going to crap and even had photos of them. So he had problems
But its your ride to do with as you wish so good luck with whatever you decide
NSF PS as for the shorty's above see Danos (post # 3) video on the working of headers, don't think you get the same effect with short ones but I could be wrong

 

Why would you buy a set of "Made in China" headers on a Vette? We have our Made in the USA TPS Motorsports RPM 1-7/8" Headers on sale right now for $899 shipped to your door which also includes GM Gaskets, Billet Catch Can, and 02 Extensions. I understand your on a budget but you'll avoid alot of fitment issue headaches and we are pretty much around 24/7 to help support you on your purchase if you need help.... from my experience eBay sellers of Chinese made parts essentially will offer you zero support.

Here is a recent review from one of our customers
https://www.corvetteforum.com/forums...er-review.html

 

^^That fitment looks awesome. Looks like they don't hang down at all. Texas Speed headers are cheap and mine made power, but they hang a bit low. BUT, I am lowered all the way on stock bolts with a bushing cut, so the car is quite low.

Those headers look great Mike, and the price tag ain't bad either!

 

Why would you buy a set of "Made in China" headers on a Vette? We have our Made in the USA TPS Motorsports RPM 1-7/8" Headers on sale right now for $899 shipped to your door which also includes GM Gaskets, Billet Catch Can, and 02 Extensions.

Good price on those headers, but will I need to buy a new X pipe along with the headers? Are the headers coated, if not how much more for that?

 

Thanks! If you decide you want to change the Texas Speed out for ours let me know