Headers for a V6

Was wondering if anyone has or knows if these headers are worth anything?
http://cgi.ebay.com/ebaymotors/MITSU...item4aabe6e8b2

I keep getting SES light for code PO431, warm-up catalyst efficiency below threshold, and am assuming that it is the front precat dying on me. I replaced the o2 sensors awhile back with the same code popping up and it didnt make it go away.

I am frustrated because I live in dumbass Cali and nothing is legal here, I want flow, but I can't get HFCs and be legal here, not to mention the cost. I figure I could put on these headers, they should fit, and get the most flow for the least hurt to my checkbook. Swap them out when smog comes along and swap back after. Looked for and couldn't find a test pipe for the precats, and headers should be better than just tossing on a test pipe, good headers at least.

If the headers I linked are crap is there any others that aren't that could be had for a decent price?

I assume that if I fashion a test pipe for the front precat and leave the rear precat as is that might create an issue with it being unbalanced? Free flow on one side and lots of back pressure on the other, please correct me if I am wrong that it would be stupid to do that.

Lastly, sorry I know I have already written a lot, is there anyway to clean a cat that is becoming plugged? I tried seafoam years ago with no change and before I read about the seafoam debate. Also I don't want to hollow the cats out, heard that it sounds like trash not to mention turbulence.

All help is appreciated, thanks guys.

unless you have soot in your cats, there is no cleaning them from what I've heard and learned in chemistry, once a catalyst is used up, you can't reverse it

the headers are probably not as crappy as most I have seen for sale, the fact they are including the diameters of the pipes does say something about the seller though. BUT, these are probably still generic knock offs, they won't give that high a gain (if you had a FED spec car), however, yes, they will flow better over the Cali spec exhaust

you probably can't run the stock manifold/pre cat on one side and then a header on the other as the y pip (to me really an F pipe in my opionion in regards to the shape), good thinking though, but it won't work

gutting out a cat (the catalyst, not the animal) won't sound like trash, it will put more rasp into the exhaust note as well as increasing noise, turbulance will only be a problem if you don't smooth out where the honey comb used to be attached

I do applaud your thinking on switching out the exhaust when it comes time for emmissions, just be weary of the police when you are driving
another option that is NOT legal but will allow you to pass smog if they don't use an exhaust probe is to use o2 sensor simulators, they will eliminate a CEL and will trick the ecu into thinking that you have functional catalysts

hope this helps

bump, I would like to hear what everyone else thinks of this conundrum he's having

1. If HFC stands for High Flow Cat there is no such thing.
2.That header will be just as good as gutting the cat, there's no way to clean it.

You might as well replace the cat so you rid yourself of the CEL.

oakrdrs187 I have seen many posts in forums and sites not linked to any cat manufacturer that shows before and after dyno results with stock, high flow cats HFC, and test pipes. From what I have read it seems that there are HFCs. I read your reply post last week with the cut and paste from www.catalyticconverter.org that claims HFCs do not exist, for others reading here is the link post #4

https://www.thegalantcenter.org/showthread.php?p=687993

Other than that site, do you have any other reference, dyno proven perhaps, that backs that claim. I am not trying to be an ass, I have an open mind and am willing to concede a point if it is proven to me, but that site doesn't do much to convince me.

Also oak you said that the headers would be just as good as a gutted cat, does that mean that those particular headers are lousy or that headers in general do not have as large an impact as I have been lead to believe? bout 4-10hp on a federal spec car.

foxbrand you mentioned that unless there is soot the catalysts can't be recovered. This had me thinking, as I had an oil leak for along time from the front valve cover, if there might have been a way for that leaked oil to have gotten down to the cat and helped clog it. Also had a random misfire years ago until I did a tuneup which may have helped soot it, but if it is just soot then maybe I can clean it and get a few more years.

Not worried about the CEL light, I made my truck into a truck dual, full flow all the way through, and used the anti-fouler trick, works great. I know it will be louder with headers but I am not changing the exhaust catback so the resonator and muffler will still be there. No matter what it wont be as loud as my truck exhaust, and I haven't been caught with that, just don't drive like an idiot around cops and they wont have a reason to pull you over.

I appreciate your input on the headers foxbrand, almost bought them but I try not to be hasty, like to do my research and get advice from those that have more experience than myself. Does anyone else have an opinion on the ebay headers?

If you read the post, it mentions that Cats with higher flow are those with less cells within the substrate. A bit more flow yes. On a race car gains may be as high as 20hp. Our V6 and I4 grocery getters 1-2 hp, and an O2 with whacked readings giving you poor Gas Milage and a CEL. Worth it? No.

In Reference to the header, it is piping with out flow restriction. 2 wks ago or so I gutted the pre-cat on my I4, when I was done it was simply a foot long oval straight pipe. My car doesn't rumble more, backfire or is it any louder/faster. The only thing is, that you can smell my exhaust from 15 feet away at idle. Now I know why Cali is so strict :phew:

As far as swaping pipes for smog, I say go for it. Buy the header and swap for smog. I'm in Cali too and I have never been pulled over and had the officer check for catalytic converters. BTW: Soon as I can afford a new pre-cat I'm getting one, only gutted it because it was clogged to the point of bogging down as I hit the throttle.

Went ahead and bought the headers, after searching through the ebay sellers feedback for someone who bought the same thing and they seemed happy with it. When I get them I will post some pics for others interested in it.

Were gonna want DYNO sheets!!!























j/k!! LOL!!

Some crappy information being given here. Foxbrand, you should at least know enough about this particular item considering we covered it on GT a while back. These headers are nothing more than "knock-off" Megan short tube headers. Same pipe diameters, design...just without the name plate.

These will suffice for the average owner and will add some better performance over stock manifolds....regardless of stock Fed spec or Cali Spec manifolds. Compare the design...it's quite obvious these will flow better.

Another thing to point out is the reason you smell fuel from removing the cat, it's because if the car isn't tuned you WILL smell fuel. These vehicles run very rich from factory for emissions standards during those production years. Tune the vehicle and the excessive fuel smell from the exhaust will be drastically reduced.

California will likely void your state inspection on these headers simply because they do not include any C.A.R.B. certifications or other documents you would need...even though they have the O2 bungs to re-install all 4 Cali spec O2 sensors....hard to get around that.

The kit is a bolt-on replacement from the header back to where the mid pipe connects, save the stock piping for future emissions testing. You should also note that these cheap headers have some issues with the exhaust stud flange holes not being 100% lined up. You can simply drill them out a little larger (maybe 1/8" or less honestly...don't remember for sure how much I did mine). They will fit just fine, and for the price...you really can't bitch too much about them

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Some crappy information being given here. Foxbrand, you should at least know enough about this particular item considering we covered it on GT a while back. These headers are nothing more than "knock-off" Megan short tube headers. Same pipe diameters, design...just without the name plate.

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really, not to get personal or off topic, I mentioned in my first post that the are probably knock offs

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Originally Posted by foxbrand

they won't give that high a gain (if you had a FED spec car), however, yes, they will flow better over the Cali spec exhaust

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Then explain the thinking behind this portion of your reply to the thread please?

Fed Spec and Cali Spec manifolds have two differences....Cali is Cast, Fed is Stamped. Both designs are highly restrictive, and any aftermarket header such as what the original posting showed, will make noticeable improvements regardless of what stock manifolds were on the vehicle....

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Originally Posted by SPD_FRK

Then explain the thinking behind this portion of your reply to the thread please?

Fed Spec and Cali Spec manifolds have two differences....Cali is Cast, Fed is Stamped. Both designs are highly restrictive, and any aftermarket header such as what the original posting showed, will make noticeable improvements regardless of what stock manifolds were on the vehicle....

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I'm not disagreeing with you, yes they flow better (hence more power most of the time) and there are gains but they aren't like the gains that happen from say a supercharger, maybe 10 whp at the absolute most is gained on a cali spec car, but with a shorty header, most of the gains are up top, there are some at the bottom end of the rpm range, but they aren't that much. In anycase, I can see some of the confusion you might have had from my first post, when I said 'they won't give you that high of a gain (if you had a FED spec car)', I should have clairify a bit more with the Cali spec manifolds, I have no actual hands on experence with them, but I should have given a bit more info on that they do flow even worse than the FED spec manifolds, so as I stated earlier, yes more gains are given on a cali spec car with headers

To say a header/s wont give you a gain is out right foolish a header is a complimentary mod to many other modifications. You might start off at 5-15 whp gained then when you add modifications like intake, cams and such they benefit greatly because of that header/s.

Its funny how the other person automatically thinks that a high flow cat will throw a code. when they make them up to obII standards. You guys should speak from experience instead of speculation. Galants have to be tuned to maximize on bolt ons we dont have the smartest ecus out there like some others.

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Originally Posted by SPD_FRK

Another thing to point out is the reason you smell fuel from removing the cat, it's because if the car isn't tuned you WILL smell fuel. These vehicles run very rich from factory for emissions standards during those production years. Tune the vehicle and the excessive fuel smell from the exhaust will be drastically reduced.

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Can you tune a stock 4g64 with stock ECU?

So question, when u say short tube design, these headers don't eliminate the stock cats?

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Originally Posted by 8thLS6

So question, when u say short tube design, these headers don't eliminate the stock cats?

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they do

Prepare for rasp if you don't plan on putting in a mid muffler.. Just in fyi for the megan style headers. I still hate my cars tone.

my cars sounds good not raspy at all!

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Originally Posted by Exhaust power

my cars sounds good not raspy at all!

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This is strictly for the v6, my comment ^^^

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Originally Posted by keith6110

This is strictly for the v6, my comment ^^^

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I know lol just teasing.

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Originally Posted by foxbrand

I'm not disagreeing with you, yes they flow better (hence more power most of the time) and there are gains but they aren't like the gains that happen from say a supercharger, maybe 10 whp at the absolute most is gained on a cali spec car, but with a shorty header, most of the gains are up top, there are some at the bottom end of the rpm range, but they aren't that much. In anycase, I can see some of the confusion you might have had from my first post, when I said 'they won't give you that high of a gain (if you had a FED spec car)', I should have clairify a bit more with the Cali spec manifolds, I have no actual hands on experence with them, but I should have given a bit more info on that they do flow even worse than the FED spec manifolds, so as I stated earlier, yes more gains are given on a cali spec car with headers

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Foxbrand...you REALLY need to just stop posting at this point. Your information is far from accurate, or even helfup.You have 0 hands on with this stuff and have yet to really even dig into your own vehicle to start giving any type of advice on a subject such as this. It would be more reasonable for you to be the one asking for the information rather than giving any.

First, why the hell are you introducing an FI (Forced Induction) component to the power output equation here when ANYBODY knows FI drastically increases output regardless of stock exhaust or aftermarket...PERIOD. Go back to basic engine theory if you need to understand this. You simply cannot compare power gains from somebody installing aftermarket headers to somebody adding a supercharger or turbo.

Second, did you completely read and understand what was stated twice before about Cali Spec and Fed Spec manifolds!? Cali Spec Manifolds are CAST, Fed Spec are STAMPED steel. Both of these manifold designs are practicaly equal in design, and the design is heavily restrictive. These manifolds are installed on the same engine, so how is "A" engine going to gain more than "B" engine when the engines are the exact same?

Third, you definitely need to go back to engine basics and understand how long tube and short tube headers affect an engine's power increase on an N/A application. Short tube headers favor more low-end to mid-range increase as the basic design simply does not allow sufficient exhaust flow for high RPM. Long tube headers favor more mid-range to high-end power increase obviously because they have more length to allow easier exhaust flow at higher RPMs.



oakrdrs187- Yes you can tune the stock engine wth your stock ECU. You can tune your setup in an N/A application, or if you go to a turbo setup you can run one of our conversion harnesses to swap in the Evo VIII ECU and tune that way.




I don't mean to come across as an asshole here, but this is really aggrivating when improper information is being given out, especially when it comes from people with no experience with the subject. We all started learning at some point, as did I...but when you don't have experience, or know for sure...don't post. All you do is steer people in the wrong direction, along with everybody else that reads that information. It does nothing for that member, or the entire community.

Well said, and thanks for the information SPD_FRK!

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Originally Posted by SPD_FRK

California will likely void your state inspection on these headers simply because they do not include any C.A.R.B. certifications or other documents you would need...even though they have the O2 bungs to re-install all 4 Cali spec O2 sensors....hard to get around that.

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Tampering with or removing the stock catalytic converters is flat out illegal here. End of story. Even if one of your cats goes bad, you are not allowed to replace it with an aftermarket or high-flow cat, it must be of OEM fit and quality.

Just a clarification.

There are three reasons why I still haven't gone to headers yet:
1) it's very illegal and will get me quite a hefty fine
2) I live in a town where the old guys will complain about my purple wheels and loud exhaust
3) my dad is a hippie so it's in my blood

And like SPD_FRK said, if you have information that has absolutely no backing whatsoever, don't put it out there.

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Originally Posted by SPD_FRK

The kit is a bolt-on replacement from the header back to where the mid pipe connects, save the stock piping for future emissions testing. You should also note that these cheap headers have some issues with the exhaust stud flange holes not being 100% lined up. You can simply drill them out a little larger (maybe 1/8" or less honestly...don't remember for sure how much I did mine). They will fit just fine, and for the price...you really can't bitch too much about them

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I can confirm what SPD_FRK said about the holes not being lined up, and yes it is an easy fix. The kit is better quality than I was expecting, welds are smoothed out, not polished, but no longer rough.

I've been taking pics and will post some after I am finished, did about half yesterday. Sprayed some PB on some stubborn nuts and called it a night.

I never even thought about the EGR valve and when I started taking things apart I saw it there in the rear exhaust manifold. Read through my Haynes manual and from what I can understand, if I just cover up the EGR port into the intake then I will
1)throw a code over the EGR not working correctly
2)engine might run a little hotter
3)nothing else will happen

Haynes talks about symptoms of a malfunctioning EGR, closed vs open valve, and it looks like only when the valve is stuck open that there would be a problem. Since capping this would effectively keep it in closed then I will have a CEL but that should be all? Can anyone confirm or correct my understanding here.

Thanks again for the help!

You can put a breather filter on the tube where air enters your egr system to prevent codes related to egr.

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Originally Posted by beam514

Tampering with or removing the stock catalytic converters is flat out illegal here. End of story. Even if one of your cats goes bad, you are not allowed to replace it with an aftermarket or high-flow cat, it must be of OEM fit and quality.

Just a clarification.

There are three reasons why I still haven't gone to headers yet:
1) it's very illegal and will get me quite a hefty fine
2) I live in a town where the old guys will complain about my purple wheels and loud exhaust
3) my dad is a hippie so it's in my blood

And like SPD_FRK said, if you have information that has absolutely no backing whatsoever, don't put it out there.

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Don't Magnaflow sales OE high flow cats?

I believe they do for some vehicles, but I'm pretty sure the fine print says they are not legal in California.

Wait.

Adrian, they say your exhaust is loud? WHAT THE I DON'T EVEN

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Originally Posted by Blue8g

Wait.

Adrian, they say your exhaust is loud? WHAT THE I DON'T EVEN

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Not currently, no. Though I do get SOME looks from here and there, just because they don't expect it from a car like this. If a mustang drives by with a louder exhaust, it's perfectly okay. lol I'm saying if I get headers I would get a ticket pretty easily around here. My friend with a 3G just got one recently.

Oooo alright.

I was like, "Wait. He's got the street series Magnaflow, I feel like that'd sound like a ghost breathing after a light jog."

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Originally Posted by beam514

I believe they do for some vehicles, but I'm pretty sure the fine print says they are not legal in California.

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They won't even ship FedSpec Cats to Cali. Sucks. You can do like a friend of mine who has a friend living in AZ. Just go pick it up after he receives it.

You can get a certain universal magnaflow cat in Cali, but only for the main cat, not the pre cats.

Follow-up - I do not recommend getting these headers. Apart from the holes not lining up where they bolt up to the engine, they also have many other defects.
-Nothing lines up well, you can get it to 'fit' but not in a good way
-It does not have clearance to go under the transmission, if there wasn't a flex joint right there (which needs to bend the opposite direction), this couldn't be done. As is it is solid against the bottom of the tranny, not ideal...
-The holes in the flanges are either too close to the welds or too close to the pipe. One out of three holes fits correctly, the others you can't fit a socket over, only the open end of a wrench. With the space limitation and lack of clearance it is very difficult to use wrenches in there, 1/6 turn at a time, was loads of fun
-The precat O2 sensor on the backside of the engine wouldn't reach the bung until I removed the connectors from the bracket that secures it, now it just reaches
-Small yet annoying additions to these issues, the stabilizer that wings out right before the main cat did not come with welded on nuts. The gaskets were not cut correctly, on one of them it blocked half the exhaust flow going into the header. Last the nuts and bolts provided for the flanges were different sizes, 16mm bolts with 14mm nuts. None of these were big issues, like I said they were just annoying.

Do yourselves a favor and go with a better quality set if you want to mod your car. This frustrated the hell out of me and I am just going to have to take it back off and send it back or eat the cost due to the non-clearance issue with under the tranny.

Grieverr

^^^That sucks. What about modifying it yourself?

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Originally Posted by Grieverr

You can get a certain universal magnaflow cat in Cali, but only for the main cat, not the pre cats.

Follow-up - I do not recommend getting these headers. Apart from the holes not lining up where they bolt up to the engine, they also have many other defects.
-Nothing lines up well, you can get it to 'fit' but not in a good way
-It does not have clearance to go under the transmission, if there wasn't a flex joint right there (which needs to bend the opposite direction), this couldn't be done. As is it is solid against the bottom of the tranny, not ideal...
-The holes in the flanges are either too close to the welds or too close to the pipe. One out of three holes fits correctly, the others you can't fit a socket over, only the open end of a wrench. With the space limitation and lack of clearance it is very difficult to use wrenches in there, 1/6 turn at a time, was loads of fun
-The precat O2 sensor on the backside of the engine wouldn't reach the bung until I removed the connectors from the bracket that secures it, now it just reaches
-Small yet annoying additions to these issues, the stabilizer that wings out right before the main cat did not come with welded on nuts. The gaskets were not cut correctly, on one of them it blocked half the exhaust flow going into the header. Last the nuts and bolts provided for the flanges were different sizes, 16mm bolts with 14mm nuts. None of these were big issues, like I said they were just annoying.

Do yourselves a favor and go with a better quality set if you want to mod your car. This frustrated the hell out of me and I am just going to have to take it back off and send it back or eat the cost due to the non-clearance issue with under the tranny.

Grieverr

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Though some of these are valid issues, they are quite minor and easily dealt with.

What transmission are you using? Automatic or Manual? If you are running these on the 3.5L or 3.8L engine this issues is not a problem as you have to modify these to clear the oil pan on the engine anyways, thus why it was never an issue for me.

You pay under $200 for a set of short tubes that have minor issues, go look at the cost of the Megan Short tube headers (identical design in fact) and come to a conclusion financially. These are very inexpensive headers, and in comparison to others of identical design these are well worth the $200 or less spent for them. Granted you have to spend some wrench time, but you at least have a good chunk of money left in your wallet to do something else, or even fill your gas tank to enjoy some driving.

Long tubes will generally cost far more than short tubes, until something else pops up for more competitive pricing you will pay top dollar for that product.

Its a 2003 3.0L with an A/T. The more I thought about it the easier the issue is, was rather frustrated when I wrote last. I can increase the clearance by adding probably 2 flanges to act as spacers on the front of the engine and 1 on the backside for a relatively good fit. Not sure if that is a good thing, having multiple flanges back to back like a double stuff oreo cookie, figure as long as I have gaskets in between each I should be alright.

About the long vs short tubes, am I right in thinking that the shorts are more for normal style of driving and longs are more of a race application? Thought I read somewhere that you will lose low end torque with long tubes if you stay under 3krpms, I rarely go over 3500rpms so it seemed shorties would be best for how this car is driven.

might be a dum question but do 3000gt headers fit the 8g? like these,

http://cgi.ebay.com/ebaymotors/OBX-9...item5ae0f5867a

^^^NO

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Originally Posted by Grieverr

Its a 2003 3.0L with an A/T. The more I thought about it the easier the issue is, was rather frustrated when I wrote last. I can increase the clearance by adding probably 2 flanges to act as spacers on the front of the engine and 1 on the backside for a relatively good fit. Not sure if that is a good thing, having multiple flanges back to back like a double stuff oreo cookie, figure as long as I have gaskets in between each I should be alright.

About the long vs short tubes, am I right in thinking that the shorts are more for normal style of driving and longs are more of a race application? Thought I read somewhere that you will lose low end torque with long tubes if you stay under 3krpms, I rarely go over 3500rpms so it seemed shorties would be best for how this car is driven.

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Believe me I can relate to the initial frustration of the fitment quality. My main concern really was the quality of the tig welds on the kit, which were surprisingly well done.

The long tube designs do favor for more mid-high RPM results which is suited more towards racing applications. The shorties are definitely an ideal upgrade for your normal daily driver. The 3.0L and 3.5L engines don't make as much benefit with long tubes on them as the cylinder heads are practically identical and really don't acheive much air flow on the top end of the RPM range. Long tubes definitely favor the newer 3.8L engine as those cylinder heads flow exceptionally well, and they have tons of torque in stock form that you won't notice much low end power loss even.

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Originally Posted by galant1983

might be a dum question but do 3000gt headers fit the 8g? like these,

http://cgi.ebay.com/ebaymotors/OBX-9...item5ae0f5867a

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The 3000GT manifolds have an oval shaped port whereas the Galant and Eclipse are rounded, you could machine the ports on the heads to match, but that requires more money spent for an already existing upgrade for the platform

The megan racing headers i have on my car that i put on after my 3.5l swap are super quiet and im on stock exhaust :). All quiet till i give it gas and car is all engine noise and away we go haha :P! <3 7 mpg city 12.5 mpg highway.

Anyways to topic. if you want decent cheap then OBX and megan, and as for raspy? it all depends on setup also. My megans are quiet. If i have some one rev engine and i go by pipe i can hear alittle rasp but not much. OBX are same way.



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