Need advice on exhaust.
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From: Houston Texas
Need advice on exhaust. 96 TA, T56, bone stock. Sig not showing for some reason.
Anyways, i have the transmission out for clutch work, i broke the three bolts on the passenger manifold when i removed the cat/y-pipe. Previous owner cut the exhaust about midway from transmission mount to rearend. So, it hung low, scraped on everything, is cracked at the ypipe behind passenger cat, and broke the hanger that bolted to the trans. So i removed it planning on getting it fixed at the muffler shop. Just doing prep work for them to cut the cost.
Anyways, since i have to remove the manifold to fix the studs, i was thinking of upgrading to headers now. I originally planned on an LSX swap, but have decided to keep the LT1 alive. So plan on upgrading this motor down the road.
I'm stuck on emissions. Should i get shorties and keep everything mostly stock emissions wise? Texas emissions cut off is 25 years, but i don't know if that will apply to OBDII cars in 2021. I could register my car with my grandparents where there are no emission checks, only safety. Is it illegal to tune my PCM to fool the emissions computer? Or, not intentionally to fool it, but a convenient byproduct of a performance tune?
I ask because I'd like to go with long tubes, and true duals eventually. But would settle on longs with a ypipe until I'm ready for the split. But i cannot find any emission legal long tubes for the dual cat cars. Or, can the PCM be tuned for a single cat, and still pass emissions? I don't want to have anything hot on my car.
So, my main question is, do i just fix the manifolds, get shorties, or is the dual cat long tubes that are emission legal?
Anyways, i have the transmission out for clutch work, i broke the three bolts on the passenger manifold when i removed the cat/y-pipe. Previous owner cut the exhaust about midway from transmission mount to rearend. So, it hung low, scraped on everything, is cracked at the ypipe behind passenger cat, and broke the hanger that bolted to the trans. So i removed it planning on getting it fixed at the muffler shop. Just doing prep work for them to cut the cost.
Anyways, since i have to remove the manifold to fix the studs, i was thinking of upgrading to headers now. I originally planned on an LSX swap, but have decided to keep the LT1 alive. So plan on upgrading this motor down the road.
I'm stuck on emissions. Should i get shorties and keep everything mostly stock emissions wise? Texas emissions cut off is 25 years, but i don't know if that will apply to OBDII cars in 2021. I could register my car with my grandparents where there are no emission checks, only safety. Is it illegal to tune my PCM to fool the emissions computer? Or, not intentionally to fool it, but a convenient byproduct of a performance tune?
I ask because I'd like to go with long tubes, and true duals eventually. But would settle on longs with a ypipe until I'm ready for the split. But i cannot find any emission legal long tubes for the dual cat cars. Or, can the PCM be tuned for a single cat, and still pass emissions? I don't want to have anything hot on my car.
So, my main question is, do i just fix the manifolds, get shorties, or is the dual cat long tubes that are emission legal?
I'm in Houston as well. Headers, including LT's are not illegal as long as they have emissions hook-ups. All your emissions stuff has to be present (AIR pump, EGR, EVAP). I have the AIR pump and EGR disabled in the tune, all codes disabled. 96 does not look for readiness checks on them, so they'll never flag. You're allowed to have two non-ready flags for your year.
You also have to have cats. They can be aftermarket, or even fakes, but they have to be there for visual. 96+ does not have a sniffer check, only plug-in check, so no issues there.
You also have to have cats. They can be aftermarket, or even fakes, but they have to be there for visual. 96+ does not have a sniffer check, only plug-in check, so no issues there.
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From: Houston Texas
It's the throwing codes in worried about. Hollowed cats will throw the o2 sensors, correct? Is my understanding simply having your service engine light on is a no pass.
Or do you tune out the o2's when they're hollowed? Forgive my ignorance on these computers, I've always had older carb cars and trucks. This is only my third vehicle with a computer. Others were a truck and a beater. Never modded them.
I'm in Houston as well. Just wondering what route i should go. I have a spare lt1 i picked up, gonna build that one up and eventually put it in. But i need exhaust work now.
I haven't seen many dual cat long tube setups. Id hollow them out if there's a way i can still pass the plug up test.
Or do you tune out the o2's when they're hollowed? Forgive my ignorance on these computers, I've always had older carb cars and trucks. This is only my third vehicle with a computer. Others were a truck and a beater. Never modded them.
I'm in Houston as well. Just wondering what route i should go. I have a spare lt1 i picked up, gonna build that one up and eventually put it in. But i need exhaust work now.
I haven't seen many dual cat long tube setups. Id hollow them out if there's a way i can still pass the plug up test.
I have a Kooks catted Y-pipe, but it was pricey. You could always get some aftermarket cats like Magnaflows and have them welded into an off-road y-pipe.
Yes, check engine light is an automatic fail. However, you can tune out the rear O2's and disable all associated code reporting for them in the tune. Any decent tuner should be able to handle that. You can get in touch with Moe (moehorsepower on here). He is in Texas and occasionally travels to Houston, but he also does mail order tunes for LT1 OBD2 cars. He tuned mine in person.
Yes, check engine light is an automatic fail. However, you can tune out the rear O2's and disable all associated code reporting for them in the tune. Any decent tuner should be able to handle that. You can get in touch with Moe (moehorsepower on here). He is in Texas and occasionally travels to Houston, but he also does mail order tunes for LT1 OBD2 cars. He tuned mine in person.
+1 getting your own high-flow cats(or hallowing) and installing them to an ORY.
As was said earlier it is easy to tune out the rear O2's in order to pass the computer test. The cat should be located after the Y-pipe merge so you only should need one cat. Make sure you get the headers you need with the correct emissions hookups as well as they come with or without them, even if you tune them out later.
After all of this you're going to want to find a cheap cat-back exhaust as well. I think you're going to be pleased how she sounds after its all done. LT1's have a thing for sounding great, especially with true duals. But I can't attest to the legality of a TD system that does not go all the way out the back and in that case you'd need two cats. Until you do more mods and/or register your car elsewhere you may want to reconsider the true dual route.
As was said earlier it is easy to tune out the rear O2's in order to pass the computer test. The cat should be located after the Y-pipe merge so you only should need one cat. Make sure you get the headers you need with the correct emissions hookups as well as they come with or without them, even if you tune them out later.
After all of this you're going to want to find a cheap cat-back exhaust as well. I think you're going to be pleased how she sounds after its all done. LT1's have a thing for sounding great, especially with true duals. But I can't attest to the legality of a TD system that does not go all the way out the back and in that case you'd need two cats. Until you do more mods and/or register your car elsewhere you may want to reconsider the true dual route.
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True dual is a later on deal. Not right now. Now my car is a dual cat setup.
what all can you tune out? Local shop doesn't even open the hood for inspection. Never has. Never even looked under any cars I've ever brought. Can you tune out the SMOG and air pump as well?
I actually don't want her to be loud while cruising. My clutch broke due to a badly world pilot bearing i couldn't hear because of the hack job exhaust. I want pipes all the way to the back, and kinda like these V8s with a mild exhaust. I really like sleeper sounding motors. More sneaky, heh heh.
I want it tasteful. Well, in reality, i plan on going back to night shift, and have a 1yr old, and another cooking in the oven. Anything quieter than it was before is a blessing. Don't give a damn about the neighbors, just wanna sneak up on the dogs to limit their barking.
Long tubes, hollowed cats, into a tasteful muffler is the plan then if i can tune them out.
That's another thing, what should i tune it for? Only mod is a 165° thermostat. Nothing else. What should i get eliminated? My security light is on, i assume it's because the keyfob is broken. Starts no problem, but alarm goes off if I lock it, then unlock with the key. Gotta start it to shut her up.
Is that vats tuned out from the pcm? Am i going to kill my gas mileage with all this?
Sorry for the loaded post.
what all can you tune out? Local shop doesn't even open the hood for inspection. Never has. Never even looked under any cars I've ever brought. Can you tune out the SMOG and air pump as well?
I actually don't want her to be loud while cruising. My clutch broke due to a badly world pilot bearing i couldn't hear because of the hack job exhaust. I want pipes all the way to the back, and kinda like these V8s with a mild exhaust. I really like sleeper sounding motors. More sneaky, heh heh.
I want it tasteful. Well, in reality, i plan on going back to night shift, and have a 1yr old, and another cooking in the oven. Anything quieter than it was before is a blessing. Don't give a damn about the neighbors, just wanna sneak up on the dogs to limit their barking.
Long tubes, hollowed cats, into a tasteful muffler is the plan then if i can tune them out.
That's another thing, what should i tune it for? Only mod is a 165° thermostat. Nothing else. What should i get eliminated? My security light is on, i assume it's because the keyfob is broken. Starts no problem, but alarm goes off if I lock it, then unlock with the key. Gotta start it to shut her up.
Is that vats tuned out from the pcm? Am i going to kill my gas mileage with all this?
Sorry for the loaded post.
If you're confident the shop doing e/m is not going to even so much as pop the hood, you can tune out/remove all emissions systems(EGR, AIR, rear 02's etc). Just a thought but since your goal is a more mild exhaust you may want to consider adding a cat to the system.
An LT1 with long tubes no cats/hallowed out cats is going to sound anywhere from fairly aggressive to loud as hell depending on the cat-back.
As far as the tune itself, you're going to be tuning it for your changes in exhaust/emissions systems. This is going to help the entire car run better, technically without any emissions systems your gas mileage might suffer a small amount. On the other hand you stand to gain a fair amount of power from just your exhaust change and the tune.
To my knowledge you can also tune out VATS but that won't turn off the security light itself. Don't quote me on that though I just straight removed all of the security BS from my last T/A.
An LT1 with long tubes no cats/hallowed out cats is going to sound anywhere from fairly aggressive to loud as hell depending on the cat-back.
As far as the tune itself, you're going to be tuning it for your changes in exhaust/emissions systems. This is going to help the entire car run better, technically without any emissions systems your gas mileage might suffer a small amount. On the other hand you stand to gain a fair amount of power from just your exhaust change and the tune.
To my knowledge you can also tune out VATS but that won't turn off the security light itself. Don't quote me on that though I just straight removed all of the security BS from my last T/A.
Last edited by Masochist; Sep 25, 2016 at 10:55 PM.
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Thread Starter
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If i hollow out the cats, doesn't that make the EGR, AIR, SMOG pointless? At what point should i stop? Just shy of ripping the whole computer out? 
As far as sound goes, i think I'll be alright with a good muffler with the LTs, hollowed cats. Hell, straight pipes out the back would be better than it is now. Really, as long as it sounds cleaner, that's all that matters. I can keep the foot off at night coming into the neighborhood.
Now I'm starting to think theta no really benefit gettingheaders if i keep everything stock emissions wise. All that cost just for a few HP isn't really worth it. Right?
As far as sound goes, i think I'll be alright with a good muffler with the LTs, hollowed cats. Hell, straight pipes out the back would be better than it is now. Really, as long as it sounds cleaner, that's all that matters. I can keep the foot off at night coming into the neighborhood.
Now I'm starting to think theta no really benefit gettingheaders if i keep everything stock emissions wise. All that cost just for a few HP isn't really worth it. Right?
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Verdad Gallardo If i hollow out the cats, doesn't that make the EGR, AIR, SMOG pointless? At what point should i stop? Just shy of ripping the whole computer out?
Now I'm starting to think theta no really benefit gettingheaders if i keep everything stock emissions wise. All that cost just for a few HP isn't really worth it. Right?
Now I'm starting to think theta no really benefit gettingheaders if i keep everything stock emissions wise. All that cost just for a few HP isn't really worth it. Right?
I've ran a full bolt-on LT1 f-body as my daily driver for quite a while before I upgraded to a Corvette. I would consider headers to be the best horsepower upgrade I did before any internal work; then again I'm also a stickler on the way my car sounds.
With a good tune a "few hp" could turn into 10-20hp on the top end and it sets the stage for future modifications. That sort of gain is enough to feel in your seat and LT1's do sound so nice.
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Consider me convinced. Long tubes, custom ypipe, PCM tune, remove EGR, AIR, and SMOG.
I just got an email from ws6store, MAC shorties W/ ypipe can be ordered and they'll ship in 3-4 weeks. About 550, no emissions.
I used Hedman headers on my older fbodies, but they don't have anything in my price range for the LT1.
I just got an email from ws6store, MAC shorties W/ ypipe can be ordered and they'll ship in 3-4 weeks. About 550, no emissions.
I used Hedman headers on my older fbodies, but they don't have anything in my price range for the LT1.
I am going to PM you a place to pick up stainless steel LT1 longtube headers and Y. You can decide how you want to go forward from there.
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I am I'm killeen tx, stationed at Fort hood, I have a 95, not sure on ur car but I just went to kwiki lube or however u spell it, passed inspection, I'm running long tube headers, all emissions torn out, no cats, I'm the poster child for what not to do, but anyways, I passed no problem, also I was on a budget and get my entire exhaust system for about 5-600 bucks, from headers to bumper, all from an eBay seller wth the name merchantsellers, I believe he has raised prices since I bought them but it's still a bargain. Best part is it is the best sounding exhaust, my friends agree too, especially the price, just go on ebay and type in 1995 camaro exhaust, it was the first item that came up in my search. But yeah man as far as inspection I would ask around and see where they do half *** inspections so u can have a great sounding exhaust without issues. Really can't say enough how great the thing sounds, it is very loud though lol, turns heads in a good way though. Never buying another type of exhaust for my car honestly
Editt* just rechecked pricing......cannot believe how much it increased, they are selling headers and y pipe for 450 and cat back for 1000.....lol wow, sorry for mis information, I guess I bought mine when the company was first starting sales or something.
Editt* just rechecked pricing......cannot believe how much it increased, they are selling headers and y pipe for 450 and cat back for 1000.....lol wow, sorry for mis information, I guess I bought mine when the company was first starting sales or something.
Last edited by Bengtson95; Sep 28, 2016 at 08:50 PM.
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No big deal. I'm just worried about the eBay stuff. Been burned too many times on ebay. Plus, everything seems like a weird translation into English in the descriptions.
But, i think I'm going to try the LPP headers. They're stainless, and i think I'm gonna go with a quiet muffler of some kind. Atleast quiet at cruising speeds.
I get the parts, i know a muffler shop that'll hook them up for me for a decent deal. And the inspection I'm good as long as i don't throw codes.
Getting paid from side projects this weekend, so I'll make the final decision after i got the cash in hand.
But, i think I'm going to try the LPP headers. They're stainless, and i think I'm gonna go with a quiet muffler of some kind. Atleast quiet at cruising speeds.
I get the parts, i know a muffler shop that'll hook them up for me for a decent deal. And the inspection I'm good as long as i don't throw codes.
Getting paid from side projects this weekend, so I'll make the final decision after i got the cash in hand.
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If i keep the cats, AND get long tubes, that would destroy all ground clearance, wouldn't it? Also make the power gains from headers negligible and higher under hood temps of I've been reading correctly. Essentially would only be upgrading for sound at that point, which isn't an upgrade for me.
Seems kinda pointless to keep all the emissions and just get headers. Or am i crazy?
It could save on the tuning required getting rid of the cats, but from what I've been reading, shorties are pointless for the most part except for a slight change in exhaust note.
The more i go that route, thinking of air quality and all that, makes having these V8 cars pointless. Should just get a 4 banger sedan........
Seems kinda pointless to keep all the emissions and just get headers. Or am i crazy?
It could save on the tuning required getting rid of the cats, but from what I've been reading, shorties are pointless for the most part except for a slight change in exhaust note.
The more i go that route, thinking of air quality and all that, makes having these V8 cars pointless. Should just get a 4 banger sedan........
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Modern high-flow performance converters will not have enough of an impact on performance to matter to your butt-dyno. The technology has come a long way from the days when a set of cats would cost you 20 horse. You will still see good gains from headers with cats. For ground clearance, that all depends on the headers. Some manufacturers are a LOT better at this than others. Same thing with temps - that's more related to the design of the headers and what coating you're getting than if you're running cats or not.
zero-hit to power on the dyno with some good cats.
And I agree with you about the smaller CID engines. I'd love to put in a GM LF3
And I agree with you about the smaller CID engines. I'd love to put in a GM LF3
Last edited by atlantadan; Oct 2, 2016 at 06:07 AM.
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If i keep the cats, i don't think there are any long tubes that'll give me decent ground clearance for Houston roads.
As far as coatings, i don't care much for them because you can barely see the exhaust on these cars. What about standard coated shorties and wrapping them? Would that help with under hood temps?
There's just not enough room under these cars to run longs with dual cats. Not without major modification any ways. Not from i can see, and I'm running with stock height suspension at the moment.
So, how about shorties wrapped? I'm not really against keeping it mostly stock at the moment. It is a mostly daily driver. I really just don't want to do pointless upgrades that won't really help anything but sounds or looks.
As far as coatings, i don't care much for them because you can barely see the exhaust on these cars. What about standard coated shorties and wrapping them? Would that help with under hood temps?
There's just not enough room under these cars to run longs with dual cats. Not without major modification any ways. Not from i can see, and I'm running with stock height suspension at the moment.
So, how about shorties wrapped? I'm not really against keeping it mostly stock at the moment. It is a mostly daily driver. I really just don't want to do pointless upgrades that won't really help anything but sounds or looks.
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Clearance - I'm sure someone on here with the same car will pipe-up soon.
The coatings are not mainly for looks - that's really a secondary reason for the application. The primary reason to get them coated is to decrease underhood temps as well as increasing longevity of the headers. It also increases the thermal efficiency due to getting the heat out of the engine. Wrapping the headers can lead to increased corrosion since 95% of the time, the wrap will be applied incorrectly.
The coatings are not mainly for looks - that's really a secondary reason for the application. The primary reason to get them coated is to decrease underhood temps as well as increasing longevity of the headers. It also increases the thermal efficiency due to getting the heat out of the engine. Wrapping the headers can lead to increased corrosion since 95% of the time, the wrap will be applied incorrectly.
I have Kooks LT's and their catted y-pipe. I am also lowered on BMR springs. The driver side cat is the lowest and has touched a few large speed bumps, and will scrape occasionally on steep driveway inclines. But that's the price you pay for having a low car, just have to learn to be more careful.
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Kooks and other high dollar ones are out of the question. 500$ is my header limit. I was thinking something stainless, but haven't found any short stainless emission legal stuff.
I'm confident I'll do the wraps right. The ceramic coated stuff is just out of my price range right now. Total exhaust budget is about 800$. That's for headers, muffler, and whatever i need in between and to the tips. Local shop is gonna trade me labor for electrical work on their shop.
So, if i go stainless headers, should i still wrap them for under hood temps? Do i need to go stainless pipe? Kinda have to if welding, right? Don't like the idea of clamps.
Didn't quite complete the side project today. I don't let people pay me until I'm done, so gotta go back. But they got more work for me, which means more money. All that means is i got time to decide. Who knows, maybe they'll give me enough to do to but some nice kooks or Dougs. Or whatever.
So, we're still on the drawing board. It's really down to keeping the emissions or not. Better gas mileage is always a plus.
I'm confident I'll do the wraps right. The ceramic coated stuff is just out of my price range right now. Total exhaust budget is about 800$. That's for headers, muffler, and whatever i need in between and to the tips. Local shop is gonna trade me labor for electrical work on their shop.
So, if i go stainless headers, should i still wrap them for under hood temps? Do i need to go stainless pipe? Kinda have to if welding, right? Don't like the idea of clamps.
Didn't quite complete the side project today. I don't let people pay me until I'm done, so gotta go back. But they got more work for me, which means more money. All that means is i got time to decide. Who knows, maybe they'll give me enough to do to but some nice kooks or Dougs. Or whatever.
So, we're still on the drawing board. It's really down to keeping the emissions or not. Better gas mileage is always a plus.