Backpressure
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Backpressure
Do The Cobalts Need Backpressure?hnking About Putting Pace Headers Leaving The Cat and putting a bullet.but if they dont need back pressure was thinking about taking off the cat.
#3
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Removing the cat will result in a check engine light, failed emissions test, a horrible sounding car, severe fines from the state if they catch you, maybe a 5 hp gain and huge torque loss. Smaller engines require backpressure to run well. We sometimes focus on horsepower that we forget about torque. It is a balancing act. I would not suggest removing it.
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What Header Should I Go With?Or Should I Start With A CAI?Thinking About Aem But I See Everyone Uses Injen Whats Better?And does Anyone Have There 2.2 Stock 1/4 Mile Times Im Bummed About Mine 16.715 Best Time.
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You should get 16flat if your stock. Some even see high 15s.
Start off slow. Sounds like you just want to throw stuff on it. Search around the 2.2L sections and get the best bang for your buck.
I was happy with the Fujita CAI.
Start off slow. Sounds like you just want to throw stuff on it. Search around the 2.2L sections and get the best bang for your buck.
I was happy with the Fujita CAI.
#7
i have an 06 SS S/C and i put a CAI and WOW...what a differance in the supercharged model...the brand intake you get really does not matter cuz i got mine off an EBAY store called GENKI TUNING it was only like $90 with shipping and it is no differant than the $250 ones out therei actually like mine better cuz it comes in black...all Mass air flow connections are perfect and everything fit great...also i put EIBACH SPORTLINE springs in and got about 1.5" drop and love it..ride quality is EXCELLENT..
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My Cobalt Is A 4 Dr Auto was looking in dragtimes.com and a stock cobalt hit 16.5 but im guessing its a 2 dr not to sure so i should just start with cai.does anyone know if the ne jet pcu helps u out i dont want my car to top out at 105 makes me lose races against all the imporsts that top out at 110 115 stock not to happy
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You drive a 4dr auto. That is the biggest problem there. Stock Cobalts can hit low 16s and high 15s. 2dr and 4dr don't have that much to do with it like people think. You are almost a full second slower than a manual.
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what is wrong with pacesetter I have it and love it unlike some it fits on the car all the bolts are easy to get to and it sounds great with the cat on not so good with it off.and I hope atleast it will not fall apart like my ca header did
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The swivel socket. Mine was leaking in 10K.
#12
You do not need back pressure period. Needing back pressure is a myth. Do a little research and you will find this. COBB Tuning has a great article about building an exhaust.
http://www.cobbtuning.com/info/?ID=3222
http://www.cobbtuning.com/info/?ID=3222
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You do not need back pressure period. Needing back pressure is a myth. Do a little research and you will find this. COBB Tuning has a great article about building an exhaust.
http://www.cobbtuning.com/info/?ID=3222
http://www.cobbtuning.com/info/?ID=3222
It is NOT a myth. I've found that out on the damn Cobalt. You lose A LOT of bottom end if you go less and less with backpressure.
#14
Read the article. I'm alittle more inclined to believe them and the millions of dollars that they pore into research over your ASS dyno again read the article. That and I have talk to several people over at COBB about exhaust Design since there shop and DYNO are right across the street from where I work.
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Read the article. I'm alittle more inclined to believe them and the millions of dollars that they pore into research over your ASS dyno again read the article. That and I have talk to several people over at COBB about exhaust Design since there shop and DYNO are right across the street from where I work.
Or better yet ask my buddy because he thought the same thing until I stomped his ass. Good backpressure gives you awesome bottom end.
#16
That is not a fair comparison. All cars are not equal when it comes to HP and TQ. Even though they may be same make, model, motor, and mileage. They will put down different #'s. There is a lot more to an exhaust than just buying it and bolting it on. You need base line #'s from the car you are working on. Then a Dyno #'s after each addition of a new part. If you change 1 # the other will change also. But it does not mean that they both will show an increase.
Another good source is a company called Dr. Gas, they do alot of NASCAR stuff and I have had this same conversaion with them. You do not want any back pressure but in that same statement you will never git rid of it unless you run a header like they do on top fuel car's. Also running a exhaust that is to large hurts low end TQ. because it slows down the exhaust gas velocity. A hot gas flows faster simple physics.
Look I'm not going to argue with you these companies send a lot of $$$$ doing research and they know what they are talking about. Besides that the ASS dyno will not be able to detect a marginal increase in HP or TQ. What I mean is a gain of 10 to 20 the ass dyno will not be able to tell but your #'s at the track will show an improvement. But only a .1 to .3 of an increase. Thats about as long as it takes to blink your eye.
Another good source is a company called Dr. Gas, they do alot of NASCAR stuff and I have had this same conversaion with them. You do not want any back pressure but in that same statement you will never git rid of it unless you run a header like they do on top fuel car's. Also running a exhaust that is to large hurts low end TQ. because it slows down the exhaust gas velocity. A hot gas flows faster simple physics.
Look I'm not going to argue with you these companies send a lot of $$$$ doing research and they know what they are talking about. Besides that the ASS dyno will not be able to detect a marginal increase in HP or TQ. What I mean is a gain of 10 to 20 the ass dyno will not be able to tell but your #'s at the track will show an improvement. But only a .1 to .3 of an increase. Thats about as long as it takes to blink your eye.
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That is not a fair comparison. All cars are not equal when it comes to HP and TQ. Even though they may be same make, model, motor, and mileage. They will put down different #'s. There is a lot more to an exhaust than just buying it and bolting it on. You need base line #'s from the car you are working on. Then a Dyno #'s after each addition of a new part. If you change 1 # the other will change also. But it does not mean that they both will show an increase.
Another good source is a company called Dr. Gas, they do alot of NASCAR stuff and I have had this same conversaion with them. You do not want any back pressure but in that same statement you will never git rid of it unless you run a header like they do on top fuel car's. Also running a exhaust that is to large hurts low end TQ. because it slows down the exhaust gas velocity. A hot gas flows faster simple physics.
Look I'm not going to argue with you these companies send a lot of $$$$ doing research and they know what they are talking about. Besides that the ASS dyno will not be able to detect a marginal increase in HP or TQ. What I mean is a gain of 10 to 20 the ass dyno will not be able to tell but your #'s at the track will show an improvement. But only a .1 to .3 of an increase. Thats about as long as it takes to blink your eye.
Another good source is a company called Dr. Gas, they do alot of NASCAR stuff and I have had this same conversaion with them. You do not want any back pressure but in that same statement you will never git rid of it unless you run a header like they do on top fuel car's. Also running a exhaust that is to large hurts low end TQ. because it slows down the exhaust gas velocity. A hot gas flows faster simple physics.
Look I'm not going to argue with you these companies send a lot of $$$$ doing research and they know what they are talking about. Besides that the ASS dyno will not be able to detect a marginal increase in HP or TQ. What I mean is a gain of 10 to 20 the ass dyno will not be able to tell but your #'s at the track will show an improvement. But only a .1 to .3 of an increase. Thats about as long as it takes to blink your eye.
#18
I'm just going to add to this topic and agree with walrus. I have several cars set up for drag racing and track use. Back pressure in an exhaust system is absolutely a myth when it comes to making a car go fast, the less the better. Same goes for a F/I vehicle, I hear alot of people on this website talking about turbo cars and them needing back pressure. Running a wide open exhaust after the turbo will gain more performance than running pipes, same will go for almost any engine i have ever had the pleasure of modding and/or dyno'ing.
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i read up on oit too cuz i was asking the same question last week. you DONT need backpressure. it sounds better if u have some but, you dont abcoutley HAVE to have it.
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I'm just going to add to this topic and agree with walrus. I have several cars set up for drag racing and track use. Back pressure in an exhaust system is absolutely a myth when it comes to making a car go fast, the less the better. Same goes for a F/I vehicle, I hear alot of people on this website talking about turbo cars and them needing back pressure. Running a wide open exhaust after the turbo will gain more performance than running pipes, same will go for almost any engine i have ever had the pleasure of modding and/or dyno'ing.
Turboed cars DON'T need any backpressure. Hell that's why I'm removing my cat on my car.
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I Think Im Going For PAcesetter Headers Will It Help Out Iff I Leave All Stock Piping or should i just get the cat back exhaust with it i was thinking monza not to good on csh and well its the cheapest anyone like how it sounds?
#22
The best bang for your buck is to put a full exhaust on it. From the head back. Go with a free flowing CAT and a muffler then find a local exhaust shop the has a mandrel bender and have them do it. I think you will be surprised at how much cheaper it is to have it built at a local shop.
#23
Removing the cat will result in a check engine light, failed emissions test, a horrible sounding car, severe fines from the state if they catch you, maybe a 5 hp gain and huge torque loss. Smaller engines require backpressure to run well. We sometimes focus on horsepower that we forget about torque. It is a balancing act. I would not suggest removing it.
wrong
Okay buy me a cobalt I'll get the exact exhaust setup I had and I'll race a cobalt with only straight pipe. You'll see which one gets off the line quicker because of bottom end torque.
Or better yet ask my buddy because he thought the same thing until I stomped his ass. Good backpressure gives you awesome bottom end.
Or better yet ask my buddy because he thought the same thing until I stomped his ass. Good backpressure gives you awesome bottom end.
i bet your buddy had an exhaust that was too big, and that was the problem. has nothing to do with backpressure. if you guys actually knew what backpressure was, i'm pretty sure you wouldn't be saying you wanted it.
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Okay buy me a cobalt I'll get the exact exhaust setup I had and I'll race a cobalt with only straight pipe. You'll see which one gets off the line quicker because of bottom end torque.
Or better yet ask my buddy because he thought the same thing until I stomped his ass. Good backpressure gives you awesome bottom end.
Or better yet ask my buddy because he thought the same thing until I stomped his ass. Good backpressure gives you awesome bottom end.
Its proper exhaust sizing that allows maximum exhaust gas velocity at the lowest amount of pressure to aid in exhaust gas scavenging.
Too large of a pipe will not allow maximum exhaust velocity. Too small and it creates backpressure.