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Discussion Starter #1
I want to install 1 7/8" X 3" MID-LENGTH HEADERS, CATTED. There is also 1 3/4"X3". Will be installing onto the OEM pipe connection. Should I get the 1 3/4" or 1 7/8"? The only other exhaust mod I have done is Magnaflow axle backs. I'm new to exhaust mods, sorry!
 

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Without other HP mods 1.75 will be fine.
 

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I thought they stopped making the 1 3/4 in mid-length? I had 1/7/8 and the only other mods I had was a Vararam intake and tune. It ran great.
 

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Discussion Starter #5
So with the VCM cai, Magnafow axle backs and a good tune (not superchips), I would be better using the 1 7/8 to be better equipped for other future mods??
And would it be a little more deep toned?
 

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We're talking 1/8 inch here, doubt it will matter.
Knowing how Kooks production goes, get whatever is in stock:)
 

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We're talking 1/8 inch here, doubt it will matter.
Knowing how Kooks production goes, get whatever is in stock:)
That 1/8 th. of an inch does make a difference. Why do you think Kooks and other header companies have 1 3/4, 1 7/8, stepped headers and so on?
 

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So with the VCM cai, Magnafow axle backs and a good tune (not superchips), I would be better using the 1 7/8 to be better equipped for other future mods??
And would it be a little more deep toned?
If you're going to cam it later down the road, get the 1 7/8. If you're just going to do simple bolt-ons, you can still get 1 7/8, but 1 3/4 will be fine.
 

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Either size will work, but I'd suggest to get the 1 7/8". No one ever regretted getting the 1 7/8" over the 1 3/4", but I bet a few have regretted getting the 1 3/4" instead of the 1 7/8". Might as well future proof your car, just in case. 😉
 

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Discussion Starter #10
I agree, I think I will get 1 7/8". It only a $10 difference. I was only asking if there was any reason not to.
 

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Discussion Starter #11
I have superchips F5 that does not have a setting for headers. So do I need a complete new tune and get rid of superchips?
 

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how much difference does that 1/8 of an inch make? i'm asking cause I really have no idea. Like at what power levels does that little difference become relevant?
 

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how much difference does that 1/8 of an inch make? i'm asking cause I really have no idea. Like at what power levels does that little difference become relevant?
As goes for power between the two, not much of a difference. Maybe someone else can explain it better. From what I know, it's all about the breathing. That's why IMO I think he should get 1 7/8 over 1 3/4. So later down the road if he chooses to cam it and so on. Now, 2 inch headers would be too much for a stock or simple bolt-on car. Header size has to be equivalent to power output. There's a chart out there, I just can't remember. There's also a chart for exhaust size to power output. Someone help me out if I'm wrong.
 

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Discussion Starter #15
To get a good tune including the transmission is approx $500 to $600?
 

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With the Stock Cam and Midpipe, the difference the 1/8" will make will be 5 HP or less. The restriction between the mid muffler and bullet mufflers and the restricted flange at the mufflers. Now you cam it big and do a full exhaust. Then you can measure the difference the larger headers can make.
So if you plan big future mods. 1 7/8 makes sense.
 

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Is there a fitment issue? My 1-3/4" mids fit great but I thought I read somewhere that the 1-7/8" ones were either too close to the plug wires or touched the plug wires.
 

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Is there a fitment issue? My 1-3/4" mids fit great but I thought I read somewhere that the 1-7/8" ones were either too close to the plug wires or touched the plug wires.
It is snugged up against the front passenger plug wire a little {mine anyways}. I thought I was going to have to get some insulators. But it didn't give me no problems as goes for burning through the plug wire {mine weren't coated either}.
 
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