header pre-purchase questions
Thread Starter
Tech Contributor
Joined: Aug 1999
Posts: 16,376
Likes: 404
From: Should this thoughtful, valuable contribution meet with no acknowledgement or 'thanks' this post----
header pre-purchase questions
I just want to be sure I understand all the terms and features for headers.
The stock motor uses 1 3/4" only. The 1 7/8 is for something else, correct?
What are 'air emissions fittings'? And when do you order them, and when is it not necessary? And why?
What are 'external harnesses' and do I need them? (extra $125)
I live in a no test state, so no problem with omitting cats...but is it a bad idea to omit them?
If I didn't like the no cat setup, I could just purchase the catted version later and swap them, correct?
Regarding the X pipe, if I want to mate directly to my Corsas, I must order 3" x 2.5", correct? I think the Corsas are 2.5" diameter.
What is a 'bung'? Sort of reminds me of Beavis and Butthead's kidding about bungholes.
Butt I am serious..LOL!
Ok, I think I covered it, but if there are any further tips and comments, fire away please...I want to do this mod b4 winter.
and do it once and right the first time.
The stock motor uses 1 3/4" only. The 1 7/8 is for something else, correct?
What are 'air emissions fittings'? And when do you order them, and when is it not necessary? And why?
What are 'external harnesses' and do I need them? (extra $125)
I live in a no test state, so no problem with omitting cats...but is it a bad idea to omit them?
If I didn't like the no cat setup, I could just purchase the catted version later and swap them, correct?
Regarding the X pipe, if I want to mate directly to my Corsas, I must order 3" x 2.5", correct? I think the Corsas are 2.5" diameter.
What is a 'bung'? Sort of reminds me of Beavis and Butthead's kidding about bungholes.
Butt I am serious..LOL!Ok, I think I covered it, but if there are any further tips and comments, fire away please...I want to do this mod b4 winter.
and do it once and right the first time.
Life Time NCM #2196
Joined: Sep 2004
Posts: 82,592
Likes: 1,711
From: Converse TX
1 3/4 headers are best for stock non blower setups and the 1 7/8 are for strokers and work fine on blower cars like mine The air fittings are for street cars and the others are for off road. I kept all my setup legal for emisisons except for I do not run cats and my setup works just fine
Get the x-pipe and I run Corsa Pacecars and use the 2 1/2" in this area so that is the way to go
The air fittings are for street cars and the others are for off road. I kept all my setup legal for emisisons except for I do not run cats and my setup works just fine Get the x-pipe and I run Corsa Pacecars and use the 2 1/2" in this area so that is the way to go
Burning Brakes
Joined: Mar 2003
Posts: 1,156
Likes: 2
From: Arlington VA
I am not sure what external harnesses are either and I have LTs. You are going to want to run the air tube setup. Some will omit or plug these but I figure why mess with the emissions system. Most LTs come with the air tubes.
If I were you, I would invest in the high flow cats and X-pipe. Yes, you could add later but then you have the added expense and labor. Get it done now. Not running cats might gain a few extra HP but you exhaust will emit a foul smell at idle.
A bung is a fitting that your O2 sensor screws into. Some folks will have an extra bung welded into the LTs prior to the collector if they plan to have somebody tune using a wide band O2 sensor. I doubt you will need this unless you know somebody who tunes this way.
You will need a good tune after the LT header install. You might want to have them omit the rear O2s so there is no chance you will get an errant MIL light down the road.
Good luck with it.
Last edited by SUPERCRUZ; Sep 27, 2007 at 11:20 PM.
Drifting
Joined: Oct 2005
Posts: 1,435
Likes: 0
From: Saint Louis MO
I bought the Dynatech Supermaxx kit with cats and the x pipe. They come with the air tubes for the emissions hook up. I've read several posts that non catted cars have a raw fuel smell. The kit I bought comes with the header bolts, gaskets and clamps. Everything you need comes in the box. I think Tbyrne (a forum sponsor) has this kit for a very competitive price. Good luck and enjoy. David
Safety Car
Joined: Mar 2006
Posts: 4,448
Likes: 4
From: Sarasota Florida
St. Jude Donor '06
I just want to be sure I understand all the terms and features for headers.
The stock motor uses 1 3/4" only. The 1 7/8 is for something else, correct?
As a generalization, 1 3/4 will make more low end, and 1 7/8 will make more top end. I would use 1 3/4 on anything under 500 rwhp.
What are 'air emissions fittings'? And when do you order them, and when is it not necessary? And why?
These are little tubes with flanges welded to the top of one header tube in each side. They are the injection points for the Air Injection Reactor system. These inject air into the exhaust during cold starts to get the catalytic converters to start working faster. There is an electric air pump at the lower right rear of the engine compartment that does this. If you look at your current manifolds, you will see where there is a hose/tube that goes into the top of the manifold on each side. That's the A.I.R. Me, I would leave the A.I.R system in place. It costs no horsepower and, given the current level of eco-hysteria, you never know when your "no test" state will change their minds.
What are 'external harnesses' and do I need them? (extra $125)
They mean "extension harnesses", not external. Headers with cats normally move the rear O2 sensor locations towards the rear of the car. The extension harnesses allow the wiring to reach back to the new locations.
I live in a no test state, so no problem with omitting cats...but is it a bad idea to omit them?
If you do a search on this you will see there are varying opinions. Putting environmental and legal concerns aside, it's been my experience that going catless stinks. It does NOT smell like the old days of Sunoco 260. Most folks report that they don't smell it too much from inside the car, but some do, and just about everyone reports that they smell it sometimes. I have followed folks with catless setups on club runs and IMO it stinks so bad as to be rude. It's just as bad, in a different way, as the guy who runs an oil-burner or a badly tuned diesel. At least some of those folks have the excuse of being bucks-down. There is no appreciable power loss with modern high-flow cats. The only downside is a few hundred for the cats. Pay it, those behind you will thank you.
If I didn't like the no cat setup, I could just purchase the catted version later and swap them, correct?
Yes.
Regarding the X pipe, if I want to mate directly to my Corsas, I must order 3" x 2.5", correct? I think the Corsas are 2.5" diameter.
Yes, just a standard setup. Very few catbacks have 3" flanges.
Ok, I think I covered it, but if there are any further tips and comments, fire away please...I want to do this mod b4 winter. and do it once and right the first time.
In that case I would only consider stainless steel headers. Personally, I would stick to American Racing, Kooks, or LG Pros. I went with ARs because they are all welded and bolted, no slip joints. LGs might make a little more midrange torque, but use slip joints in the x-pipe. I'm very happy with the ARs, but there are other good headers as well.
The stock motor uses 1 3/4" only. The 1 7/8 is for something else, correct?
As a generalization, 1 3/4 will make more low end, and 1 7/8 will make more top end. I would use 1 3/4 on anything under 500 rwhp.
What are 'air emissions fittings'? And when do you order them, and when is it not necessary? And why?
These are little tubes with flanges welded to the top of one header tube in each side. They are the injection points for the Air Injection Reactor system. These inject air into the exhaust during cold starts to get the catalytic converters to start working faster. There is an electric air pump at the lower right rear of the engine compartment that does this. If you look at your current manifolds, you will see where there is a hose/tube that goes into the top of the manifold on each side. That's the A.I.R. Me, I would leave the A.I.R system in place. It costs no horsepower and, given the current level of eco-hysteria, you never know when your "no test" state will change their minds.
What are 'external harnesses' and do I need them? (extra $125)
They mean "extension harnesses", not external. Headers with cats normally move the rear O2 sensor locations towards the rear of the car. The extension harnesses allow the wiring to reach back to the new locations.
I live in a no test state, so no problem with omitting cats...but is it a bad idea to omit them?
If you do a search on this you will see there are varying opinions. Putting environmental and legal concerns aside, it's been my experience that going catless stinks. It does NOT smell like the old days of Sunoco 260. Most folks report that they don't smell it too much from inside the car, but some do, and just about everyone reports that they smell it sometimes. I have followed folks with catless setups on club runs and IMO it stinks so bad as to be rude. It's just as bad, in a different way, as the guy who runs an oil-burner or a badly tuned diesel. At least some of those folks have the excuse of being bucks-down. There is no appreciable power loss with modern high-flow cats. The only downside is a few hundred for the cats. Pay it, those behind you will thank you.
If I didn't like the no cat setup, I could just purchase the catted version later and swap them, correct?
Yes.
Regarding the X pipe, if I want to mate directly to my Corsas, I must order 3" x 2.5", correct? I think the Corsas are 2.5" diameter.
Yes, just a standard setup. Very few catbacks have 3" flanges.
Ok, I think I covered it, but if there are any further tips and comments, fire away please...I want to do this mod b4 winter.
and do it once and right the first time.In that case I would only consider stainless steel headers. Personally, I would stick to American Racing, Kooks, or LG Pros. I went with ARs because they are all welded and bolted, no slip joints. LGs might make a little more midrange torque, but use slip joints in the x-pipe. I'm very happy with the ARs, but there are other good headers as well.
Thread Starter
Tech Contributor
Joined: Aug 1999
Posts: 16,376
Likes: 404
From: Should this thoughtful, valuable contribution meet with no acknowledgement or 'thanks' this post----
Man o man! thanks guys...I learned a few things as usual...can you imagine trying to get educated on this without the forum? Yes, I am leaning right now toward American Racing and Dynatech...I dig the idea of having all the parts necessary for the installer, and the comments everywhere about the fit and finish on these two are swaying me in that direction. One more ?...Is a tune really needed afterward? My engine is stock, but for the Stinger.
Drifting
Joined: Oct 2005
Posts: 1,435
Likes: 0
From: Saint Louis MO
After I installed my headers, I got a dyno tune. The tuner turned off the rear 02 sensors, that way I won't take a chance on getting codes. I really think it's worth the money. Tuners refer to it as 02 delete. As far as fit and finish, the Dynatech Supermaxx kits are all stainless steel. I had my headers Jet Coated to cut down on heat. This was my first header install, it took time but was not hard. Follow the instructions, take your time. Remove the spark plugs so you don't crack them and have problems with codes when you start your car. I've read many posts on broken spark plugs and header installs. AR, LG, KOOKS, and several others make great products. I chose mine because of the completeness of the kit. David
This photo was taken during the install. Nothing had been tightened at this point.
This photo was taken during the install. Nothing had been tightened at this point.
Thread Starter
Tech Contributor
Joined: Aug 1999
Posts: 16,376
Likes: 404
From: Should this thoughtful, valuable contribution meet with no acknowledgement or 'thanks' this post----
Man, I just love that beefy look! I am pricing these now...best I've found so far is $1606 with free shipping. Any forum vendors want to beat that price? jgira12@yahoo.com to reply privately
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