header downpipe questions (confused)
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From: NJ
header downpipe questions (confused)
I know there has probably been tons of threads about this but I am searching everywhere and looking on here and there is just so much info about exhaust it is crazy in your guys opinion what is the best header and downpipe brand and combination for my cobalt ss 2.4L? I def want to go catted downpipe because of emission reasons but not sure what would be better Shorty, midlengh, or longtube... I’m new to engine mods I would love the input.
I have an injen intake btw
I have an injen intake btw
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From: East Brunswick, NJ
Being that you have a 4 cylinder, they're all going to result in similar powerbands and power achieved. 4-1 design is typically for shifting power upwards, 4-2-1 design is typically going to give you a smooth torque increase and overall power increase.
Really, you can't go wrong either way because it will be an upgrade from what you have from the factory. My main piece of advice is to try and get one that is coated (ceramic coated) and just read peoples reviews on fitment so you have no fitting issue.
Personally, I wouldn't look to change out the header until you do the rest of your exhaust first, thats just me.
Really, you can't go wrong either way because it will be an upgrade from what you have from the factory. My main piece of advice is to try and get one that is coated (ceramic coated) and just read peoples reviews on fitment so you have no fitting issue.
Personally, I wouldn't look to change out the header until you do the rest of your exhaust first, thats just me.
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You really need both, but if budget is a problem, try to find a used stock LSJ downpipe first. Then you can add a header at a later date when your budget permits.
IMO the downpipe is more of a restriction on the 2.4 than the manifold, especially if you have an 08 with two cats.
IMO the downpipe is more of a restriction on the 2.4 than the manifold, especially if you have an 08 with two cats.
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will the ZZP 2.5 inch stainless catted downpipe fit with a long tube header? its a 3 in downpipe but at the exit goes to 2.5in or do i need to go midlength header? which is better longtube or mid length?
another question do i wana add a 02 bung for wideband? what is that anyways?
another question do i wana add a 02 bung for wideband? what is that anyways?
No the long tube has a special short down pipe since the LONG tubes are long 
Wideband is an a/f (air/fuel) ratio gauge if you don't have one nor know what it is you prob don't need it unless you plan to tune or go f/i
What to get depends on where you want your power to be. Do you want acceleration? (shorty) Mid power? (middle of rpms get power this is midlength good example for this is if you do a lot of roll racing) or top end power? (long tube) Of course that means not much power in acceleration since all your power is at the top which means you gain speed in the long run but no power for take off
Wideband is an a/f (air/fuel) ratio gauge if you don't have one nor know what it is you prob don't need it unless you plan to tune or go f/i
What to get depends on where you want your power to be. Do you want acceleration? (shorty) Mid power? (middle of rpms get power this is midlength good example for this is if you do a lot of roll racing) or top end power? (long tube) Of course that means not much power in acceleration since all your power is at the top which means you gain speed in the long run but no power for take off
Last edited by slobalt08; Mar 3, 2011 at 08:46 PM.
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A shorty header generally benefits high end power at the expense of low end torque. A mid range tries to be all things to all people, but who knows? A long tube generally benefits low end torque at the expense of high end power. Which is better? How do you drive your car?
A long tube would be more "street friendly". A shorty will usually provide a top end screamer.
A long tube would be more "street friendly". A shorty will usually provide a top end screamer.
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A shorty header generally benefits high end power at the expense of low end torque. A mid range tries to be all things to all people, but who knows? A long tube generally benefits low end torque at the expense of high end power. Which is better? How do you drive your car?
A long tube would be more "street friendly". A shorty will usually provide a top end screamer.
A long tube would be more "street friendly". A shorty will usually provide a top end screamer.
a shorty is for low-end power and a long-tube is for high end.
think of it this way. if the header is shorter the exhaust gasses will travel shorter distance so it will give you a low end bump. if its longer it will take longer time to exit so it will give you a high end bump.
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First website listed when I googled exhaust header length. CarCraft magazine was one of the biggie hot rod magazines back in the sixties and seventies.
Header Basics - How Headers Contribute to Horsepower - Car Craft Magazine
Quoted. "Primary pipe length can also skew an engine's power curve based on length changes. Primary-pipe diameter establishes the peak torque point, so changing the pipe length will rock the output curve by pivoting it around that peak torque point. Graph B shows how longer tubes tend to increase power below peak torque while hurting power above peak torque. Shorter tubes tend to affect the engine in exactly the opposite way, hurting midrange torque in favor of increasing top-end power."
Header Basics - How Headers Contribute to Horsepower - Car Craft Magazine
Quoted. "Primary pipe length can also skew an engine's power curve based on length changes. Primary-pipe diameter establishes the peak torque point, so changing the pipe length will rock the output curve by pivoting it around that peak torque point. Graph B shows how longer tubes tend to increase power below peak torque while hurting power above peak torque. Shorter tubes tend to affect the engine in exactly the opposite way, hurting midrange torque in favor of increasing top-end power."
ok so.. i have an SS lsj.. idk if you would want my input, but search for used parts as well.. i got a used vibrant header and dp from a buddy of mine.. was a BEECH to install the header, but i loved it after..and dooooo make sure your dp matches your header and your O2 sensor as well... cuz i had to fabricate my O2 sensor lol... oh well, who cares if i the the CEL for it
Generally speaking, the length of the tubes shift your powerband higher or lower, robbing some power from the opposite end of the spectrum. You need to decide whether you want more low end, midrange, or high end, then choose your header accordingly.
i.e. -
- a shorty header would provide good low end torque, but would make your car feel out of breath in the upper rpm ranges due to the restriction
- a mid-length header would feel a little sluggish in the lower rpms, more confident in the midrange, and better than a shorty in the upper ranges.
- a longtube header would feel wheezy down low and through the lower parts of the midrange, likely producing less torque than stock, but would really come alive in the uppder midrange and top end.
THAT IS OF COURSE, assuming your engine can pump enough exhaust to fill it up. A good shorty header should be more than enough on a car making anything 250whp or less.
The key is to match the header to your current or planned output.
i.e. -
- a shorty header would provide good low end torque, but would make your car feel out of breath in the upper rpm ranges due to the restriction
- a mid-length header would feel a little sluggish in the lower rpms, more confident in the midrange, and better than a shorty in the upper ranges.
- a longtube header would feel wheezy down low and through the lower parts of the midrange, likely producing less torque than stock, but would really come alive in the uppder midrange and top end.
THAT IS OF COURSE, assuming your engine can pump enough exhaust to fill it up. A good shorty header should be more than enough on a car making anything 250whp or less.
The key is to match the header to your current or planned output.
A shorty header generally benefits high end power at the expense of low end torque. A mid range tries to be all things to all people, but who knows? A long tube generally benefits low end torque at the expense of high end power. Which is better? How do you drive your car?
A long tube would be more "street friendly". A shorty will usually provide a top end screamer.
A long tube would be more "street friendly". A shorty will usually provide a top end screamer.
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From: On Earth
Generally speaking, the length of the tubes shift your powerband higher or lower, robbing some power from the opposite end of the spectrum. You need to decide whether you want more low end, midrange, or high end, then choose your header accordingly.
i.e. -
- a shorty header would provide good low end torque, but would make your car feel out of breath in the upper rpm ranges due to the restriction
- a mid-length header would feel a little sluggish in the lower rpms, more confident in the midrange, and better than a shorty in the upper ranges.
- a longtube header would feel wheezy down low and through the lower parts of the midrange, likely producing less torque than stock, but would really come alive in the uppder midrange and top end.
THAT IS OF COURSE, assuming your engine can pump enough exhaust to fill it up. A good shorty header should be more than enough on a car making anything 250whp or less.
The key is to match the header to your current or planned output.
i.e. -
- a shorty header would provide good low end torque, but would make your car feel out of breath in the upper rpm ranges due to the restriction
- a mid-length header would feel a little sluggish in the lower rpms, more confident in the midrange, and better than a shorty in the upper ranges.
- a longtube header would feel wheezy down low and through the lower parts of the midrange, likely producing less torque than stock, but would really come alive in the uppder midrange and top end.
THAT IS OF COURSE, assuming your engine can pump enough exhaust to fill it up. A good shorty header should be more than enough on a car making anything 250whp or less.
The key is to match the header to your current or planned output.
go mid unless u plan on racin. I always like the torque for daily drivin cause im not always reving the car at 5k+rpms to feel the power increase
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So a mid length header will pretty much be my best bet because it would benefit all around because with a Shorty I’m losing upper rpm power and long tube I’m losing low end rpm power
Correct me if I’m wrong this is just how I’m taking the information here... like is said earlier I’m new to this engine talk
Correct me if I’m wrong this is just how I’m taking the information here... like is said earlier I’m new to this engine talk
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From: nova scotia
So a mid length header will pretty much be my best bet because it would benefit all around because with a Shorty I’m losing upper rpm power and long tube I’m losing low end rpm power
Correct me if I’m wrong this is just how I’m taking the information here... like is said earlier I’m new to this engine talk
Correct me if I’m wrong this is just how I’m taking the information here... like is said earlier I’m new to this engine talk
While im a fan of zzps stuff and they will have plenty of future business from me. The collector flange on the mid length they sell is a 2 bolt and is prone to exhaust leaks.
So I honestly recommend their longtube if you have the cash. But if your on a budget then id go with a badmab header and a catted 3 inch to 2.5 zzp downpipe. (though thats probably only around 100 bux cheaper) I have a shorty on the stock downpipe currently and I felt a small gain. But not nearly the same gain as i felt when i had the mid length with a 3 inch to 2.5 inch catted downpipe setup. It definitely pulled harder. So the downpipe is a choking point on the 2.4s (dual cats plus a pinched tube doesnt help).
Honestly on these cars that catback isnt worth much other than some sound and maybe a handful of hp. Most of the power will be from the header/dp.
So I honestly recommend their longtube if you have the cash. But if your on a budget then id go with a badmab header and a catted 3 inch to 2.5 zzp downpipe. (though thats probably only around 100 bux cheaper) I have a shorty on the stock downpipe currently and I felt a small gain. But not nearly the same gain as i felt when i had the mid length with a 3 inch to 2.5 inch catted downpipe setup. It definitely pulled harder. So the downpipe is a choking point on the 2.4s (dual cats plus a pinched tube doesnt help).
Honestly on these cars that catback isnt worth much other than some sound and maybe a handful of hp. Most of the power will be from the header/dp.
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While im a fan of zzps stuff and they will have plenty of future business from me. The collector flange on the mid length they sell is a 2 bolt and is prone to exhaust leaks.
So I honestly recommend their longtube if you have the cash. But if your on a budget then id go with a badmab header and a catted 3 inch to 2.5 zzp downpipe. (though thats probably only around 100 bux cheaper) I have a shorty on the stock downpipe currently and I felt a small gain. But not nearly the same gain as i felt when i had the mid length with a 3 inch to 2.5 inch catted downpipe setup. It definitely pulled harder. So the downpipe is a choking point on the 2.4s (dual cats plus a pinched tube doesnt help).
Honestly on these cars that catback isnt worth much other than some sound and maybe a handful of hp. Most of the power will be from the header/dp.
So I honestly recommend their longtube if you have the cash. But if your on a budget then id go with a badmab header and a catted 3 inch to 2.5 zzp downpipe. (though thats probably only around 100 bux cheaper) I have a shorty on the stock downpipe currently and I felt a small gain. But not nearly the same gain as i felt when i had the mid length with a 3 inch to 2.5 inch catted downpipe setup. It definitely pulled harder. So the downpipe is a choking point on the 2.4s (dual cats plus a pinched tube doesnt help).
Honestly on these cars that catback isnt worth much other than some sound and maybe a handful of hp. Most of the power will be from the header/dp.
Isn’t the badmab a Shorty header? What kind of mid length are you running? I’m having trouble finding mid lengths and whenever I do find them they are out of stock… and I’m definitely going to use that downpipe that you have I was looking into that one I liked what I read about it
i would save up and get all the exhaust stuff u want all at once. its just a pain in the ass the get everything off and put it back on. then to do it AGAIN!? itd be annoying. when i got my exhaust i got it all at once. well.. i got my downpipe and header then waited to get my catback for a week. got it then did it ALL at one time.
Not to mention with my car you have to cut the catback in order to get it off. im sure you can get the downpipe off with the catback still on but itll probobly be a pain
Not to mention with my car you have to cut the catback in order to get it off. im sure you can get the downpipe off with the catback still on but itll probobly be a pain
I'm thinking in the future of getting the zzp midlength header/ dp combo with a Borla catback system. My question is, is the dp 3" or 2.5" and how would I get it to fit the 2.25" Borla catback?