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Discussion Starter #1
Do they? Read in topics that people lost low-range torque...which doesnt makes sense to me since they increase airflow, how can they decrease it?
Anyone have dynos to prove this wrong or right?

And before anyone says ANYTHING about backpressure, EDUCATE yourself.
 

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also interested since my set JUST arrived on my doorstep. :hi:
 

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I think it is because they reduce they back pressure which is required at low RPMs to create torque
 

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i think you guys dont have a clue what you are talking about, torque follows hp. if you are losing torque that means you are losing hp. just does not sound right to me. But what do i know, i have only been building race engines for the past 8 years.
 

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Is there ANY sort of power loss of performance decrease when installing aftermarket headers? I think that may be the most general and objective question...
 

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this is all talk about losing torque at low rpm's, i see the posts all day long. The key word is " It feels like i am losing torque at low rpms". Someone needs to post some dyno charts or something.
 

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this is what happened to me, before i got the ebay headers, with oem header, on my step tranny, when i would press the gas all the way down to the button it would give it a nice kick and a nice change in gears, but now after the headers, its not that much of a kick, its more smooth, or i should say less kick, but its well worth the mid and high end power gains, its not a big difference, plus as i said before the 3.91 diff or 3,46 diff should take care of that really well.
 

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but it could just be the sound or it might just be in your head. The only way anyone is going to figure this out is to do a dyno run before and after. I just put a set of headers on my 325 and i cant tell of any torque loss at all. If anything i gained a little down low and a ton up top.
 

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but it could just be the sound or it might just be in your head. The only way anyone is going to figure this out is to do a dyno run before and after. I just put a set of headers on my 325 and i cant tell of any torque loss at all. If anything i gained a little down low and a ton up top.
Na its not in my head, i can feel it, maybe your car wasnt in good shape and it wouldnt kick you into your seat :hmm:
 

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maybe its the fact that it pulls harder than normal in the upper RPM's, which leads you to believe that it doesnt have as much of a kick in the lower RPM's... the high end power more or less tricks you into believing that your lower end isnt as powerful... i hope i made sense... it seems like the only reasonable answer to why everyone is saying this. Nothing else makes sense.

EDIT- i am totally going out on a limb on this one, so no flaming if i make a complete ass out of myself for saying something completely unreasonable :p
 

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Discussion Starter #13
maybe its the fact that it pulls harder than normal in the upper RPM's, which leads you to believe that it doesnt have as much of a kick in the lower RPM's... the high end power more or less tricks you into believing that your lower end isnt as powerful... i hope i made sense... it seems like the only reasonable answer to why everyone is saying this. Nothing else makes sense.

EDIT- i am totally going out on a limb on this one, so no flaming if i make a complete ass out of myself for saying something completely unreasonable :p
That actually made sense, to me atleast. Look at a racing engine, it's as free-flowing as it gets.

I wish I had access to a dyno..dammit.
 

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maybe its the fact that it pulls harder than normal in the upper RPM's, which leads you to believe that it doesnt have as much of a kick in the lower RPM's... the high end power more or less tricks you into believing that your lower end isnt as powerful... i hope i made sense... it seems like the only reasonable answer to why everyone is saying this. Nothing else makes sense.

EDIT- i am totally going out on a limb on this one, so no flaming if i make a complete ass out of myself for saying something completely unreasonable :p
no trust me guys i feel it. its not in my head , i do feel the difference.
 

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having headers i can say this. ** This is all by feel no dynos sorry**

no tune -

the car will be more responsive to the throttle but feel like its lost torque. driving it for a while will help the computer "figure out" how to handle it. it will go up a little but not alot over the stock.

tune -

lots and lots of torque. enough to make stationary objects laying on floor or in sunglass holder fly towards the rear of the car during any heavy accelleration from 1st on. now im not talking about a launch. havent done that in a long time :)
 

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what kind of tune are we talking about here... like an AA tune?
 

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what kind of tune are we talking about here... like an AA tune?
i have powerchip software. local tuner for me. theyre over in newport beach
 

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My 330 might have not gained as much torque as horsepower(the stock zhp dyno has similar torque to my modded 330), but it definitely didn't lose low end torque. If anthing, its got torque at a lower rpm now. I can't back that up with a dyno, unfortunately my dyno didn't start till almost 3k, but my torque curve was relatively flat, though it did gradually raise till rev limit. I don't have my dyno here(I'm on vacation in Kentucky right now) but I wanna say It was close to 200lb-ft
 

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i think you guys dont have a clue what you are talking about, torque follows hp. if you are losing torque that means you are losing hp. just does not sound right to me. But what do i know, i have only been building race engines for the past 8 years.
Torque only follows hp to 5252 rpm though, as horsepower is a function of torque...
 
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