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14.09 @ 95.53mph!!
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I am trying to figure out which one I am gonna do. This will be my last mod and I wanna get the best bang for the buck. I currently have Nismo CAI and Greddy EVO2, and wanna get a little more power out of her. So I have decided to finish with either the downpipe or the header. Now I know that I will loose 1 cat with either one that I do, so that will help a little Im sure, and I have read that the downpipe has shown 3hp and 5ft lbs of torque with 8fts between like 3-4,000rpms (correct me if I am wrong about the info) and that sounds pretty good. That along with the fact I dont have to do any modifying to my o2 wiring etc regardless of how easy it is, I dont have to worry about the header install which I heard can be a pain, and I dont have to worry about police seeing my header and forcing me to go to the smog ref (live in San Diego), which intails doing the sh1tty header install just to get it to pass... so that is the info weighing on me getting the downpipe...

Now of course as we all know the header is the biggest HP gaining bolt-on you can do, so that is an obvious good side, but as I said above... the install, o2 crap, and police crap have all made me think twice...

So...I ask you, what would you do? Go with a little more stealthy bolt-on with modest gains (downpipe) or go with the best gains but the chance of getting caught by the fuzz (especially since Ive read that it will make the exhaust loud, and police here love to pull over cars that are loud)?

by the way, do you think it would be fairly easy to somehow mount the oem header heat shield to the aftermarket header? Then I wouldnt have to worry about a police officer asking me to open the hood bc then they couldnt see anything... :D
 

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itd be easier to pass emissions with a header than a downpipe...]

if youre worried about the cops, go the header route... actually, even if you arent worried about the cops, go the header route... definitely a worthwhile mod... if you want a little more power with no more noise or emissions, you could always buy a pulley... or s-afcII for that matter...
 

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It's actually not a downpipe, but a midpipe, coming from the end of your header, to the catback system.
 

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14.09 @ 95.53mph!!
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Discussion Starter #4
I honestly think it would be harder...if I have emissions testing just undo a couple bolts pull off the straight pipe put back the stock one and be done in 45mins...or 2-4hours of wrenching a header into a cramped space that takes a lift to be done...and police can see the header...not the downpipe

okay its a midpipe, but the name of the product is HP Autoworks Downpipe...just copying what they call it, not getting technical
 

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Foolishly Impractical
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I'd go header.. put the stock heatshield back on and it will take one hell of a sharp cop to know wtf is going on there. Its a bit more work than the midpipe but the gains are better.
 

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NatlCitySentra said:
I honestly think it would be harder...if I have emissions testing just undo a couple bolts pull off the straight pipe put back the stock one and be done in 45mins...or 2-4hours of wrenching a header into a cramped space that takes a lift to be done...and police can see the header...not the downpipe

okay its a midpipe, but the name of the product is HP Autoworks Downpipe...just copying what they call it, not getting technical
with the downpipe, you have no main cat... have you ever smelled a car running no cat? anyone who knows cars can tell... i know theyre pretty strict in cali, and im guessing that the smell could be reason enough to pull you over and take a peek...
 

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03blackout said:
with the downpipe, you have no main cat... have you ever smelled a car running no cat? anyone who knows cars can tell... i know theyre pretty strict in cali, and im guessing that the smell could be reason enough to pull you over and take a peek...
and plus.... the header is way worth the extra work...

just move to jersey, i can get you to pass emissions with flying colors...2 cats, no cats, no mufflers... we dont care...

(oops, this was supposed to be an edit of my previous post... oh well, you win some you lose some)
 

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Next to the jwt clutch flywheel combo, the header is the biggest gain I've felt after putting it on the car. I'd go with the header first.
 

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specVracing said:
Next to the jwt clutch flywheel combo, the header is the biggest gain I've felt after putting it on the car. I'd go with the header first.
stop making me jealous with your clutch/flywheel... i want that setup so bad... its soo tempting....
 

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NatlCitySentra said:
I honestly think it would be harder...if I have emissions testing just undo a couple bolts pull off the straight pipe put back the stock one and be done in 45mins...or 2-4hours of wrenching a header into a cramped space that takes a lift to be done...and police can see the header...not the downpipe

okay its a midpipe, but the name of the product is HP Autoworks Downpipe...just copying what they call it, not getting technical

Odd. Andy will have to fix that typo.
 

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03blackout said:
stop making me jealous with your clutch/flywheel... i want that setup so bad... its soo tempting....

It will make your NA feeling come much more alive. I love the simple downshifts... mmm it's like buttah!
 

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specVracing said:
It will make your NA feeling come much more alive. I love the simple downshifts... mmm it's like buttah!
damn you... id like to do 13's on a stock motor before i start building it... and i think slicks will do it for me... so im thinking some 22.5" slicks and then the jwt clutch/flywheel...
 

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Well see, that's where the problem enlies for me. Fastest I pulled BEFORE the c/f combo was 14.61. After the install and circa 400 mile break in, I ran at the track this weekend, and basically 1st and 2nd gear were useless. I had no traction at all coming out of the whole due to the regaining of the horsepower. Fastest I pulled was a 15.01 with terrible 60' times. So I HIGHLY suggest getting some sticky grippy tires when doing the jwt clutch flywheel.
 

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specVracing said:
Well see, that's where the problem enlies for me. Fastest I pulled BEFORE the c/f combo was 14.61. After the install and circa 400 mile break in, I ran at the track this weekend, and basically 1st and 2nd gear were useless. I had no traction at all coming out of the whole due to the regaining of the horsepower. Fastest I pulled was a 15.01 with terrible 60' times. So I HIGHLY suggest getting some sticky grippy tires when doing the jwt clutch flywheel.
if all goes according to plan, i think some slicks will push me into the 13s... if not, slicks + the jwt combo definitely will... maybe ill be the first to do 13's all motor, but who knows... i start my first year of college on friday, so i dont know how the money issue is going to work out...
 

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Well yeah, I was planning to run atleast real low 14's. thats how the gains felt on the street, but gaining that traction at the 1/4 is a pain in the rump. Good luck.
 

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specVracing said:
Well yeah, I was planning to run atleast real low 14's. thats how the gains felt on the street, but gaining that traction at the 1/4 is a pain in the rump. Good luck.
thanks dude, well give this character his thread back...

[/hijack]
 

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14.09 @ 95.53mph!!
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Discussion Starter #18
well its all good... at least I got some answers...still a little iffy... I just dont wanna get too involved with this car I would much rather wait save and get some RWD in the future...and so I am very unsure what I wanna do as not to blow tons of money on this car...
 

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Theory freak learning...
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1 piece header like Nismo or Hotshot and downpipe are 2 differents mods that complete each other.

I'm not sure to understand well the question here but 1 thing is sure, get the downpipe WITHOUT the header would be almost worthless... because you still have that big restriction at the engine output, the increased size, cat free downpipe won't give you real benefit.

Get the header ASAP and get rid of the pre-cat s h i t so your engine will remain in good shape and you would gain more than 10HP to the wheel ;)
 

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Immature Tough Guy
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angel2167882 said:
Get the header ASAP and get rid of the pre-cat s h i t so your engine will remain in good shape and you would gain more than 10HP to the wheel ;)
I agree with this more than anything. The QR25 precat breaking up and pieces getting sucked back into the engine is arguably the most serious problem owners have faced and it prompted Nissan to issue that recall. Whether this happens to 1% of all QR25s or 5% is irrelevant when you can simply remove the source of the problem entirely with an aftermarket header. So you have a bolt on mod with great gains and it can potentially save your engine. I didn't just take my exhaust manifold off, I gave it away to Travis two years ago, because that thing is never touching my engine again.
 
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