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Old 02-21-2013, 09:56 AM   #1
booSTin-scoobs
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Default Sluggish with headers

What's up guys. So I google searched a little and may have found an answer but I want your guys opinions. A while back I was running a vf39 on my 04 wrx, 2.0. I was running cobb ots map and it felt a lot better than td04 obviously. But then I installed a set of el one piece headers (el, I know you don't have to say it) and the car then seemed a little more sluggish. It just wasn't as quick as it was before the install. Not by a lot just enough for me to notice the response wasn't as well. However I know have an fp18g on and I'm dropping the car off tonight at TPG tuning for Nate to tune for that 18g and I'm worried those headers are gonna make me lose power. I know to get full potential of headers you need tuned for them but I just want everything to go smoothly and don't want anything that's going to cause me to lose power when he's tuning. What do you guys think, is this normal, has anyone else experienced this before their tune but after it was worth it? Let me know
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Old 02-21-2013, 10:09 AM   #2
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Wihtout a retune, the EL headers will feel more sluggish because typically you will run a little richer due to the more efficient design. I had to pull some fuel from the map in order to get the AFR back where it was.
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Old 02-21-2013, 10:15 AM   #3
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Yea I mean I know you need a tune for them. The only reason I was concerned about it was bc my tuner said I shouldn't have lost any power
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Old 02-21-2013, 10:26 AM   #4
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Are they nice headers or the el crapo ebay special?

Many cheap headers are "designed" for big flow and larger volumes of gasses by using big bore pipes. High quality headers are a good compromise between flow volume and velocity. The stock headers have basically minimal volume to help spool and you likely added way more volume by switching to aftermarkets.
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Old 02-21-2013, 10:29 AM   #5
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To be honest I'm not sure the brand. However the bore doesn't seem that big and they have slip joints so I doubt they're eBay specials. Also I didn't need to change my oil pan to install them so I don't think they're eBay headers
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Old 02-21-2013, 10:30 AM   #6
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Also aren't most eBay headers 2 piece?
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Old 02-21-2013, 10:35 AM   #7
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Yes, because slip joints are too expensive and indicative of high quality.

not for these ebay specials

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Old 02-21-2013, 10:40 AM   #8
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Mine dont look anything like those so I don't think they're cheap eBay ones
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Old 02-21-2013, 10:41 AM   #9
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And if they were cheap eBay headers does that mean I'm gonna lose power on the dyno?
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Old 02-21-2013, 11:11 AM   #10
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Did you wrap the headers before you put them on??
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Old 02-21-2013, 11:18 AM   #11
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Yea I wrapped em up good
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Old 02-21-2013, 11:20 AM   #12
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Yea I wrapped them good. But actually looking closer at that second pic lukeskywrx put up, the one on the right looks a lot like the header I have
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Old 02-21-2013, 11:56 AM   #13
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I've driven several exhaust manifold / header combinations. After doing so, there are two I'd use:

1) stock exhaust manifold
2) 2.5L oil pan style EL headers (perrin / 3 bolt chinese copy style / KillerB / Full-Race)

The EL headers that clear the 2.0L oil pan are a net loss from all the extra piping and/or sharp bends. The UEL are too top end oriented. Every one will lose quite a bit of spool.

My opinion is to stay stock unless you are changing your oil pan.
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Old 02-21-2013, 12:03 PM   #14
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^^^Troof...I went from Cusco UEL headers to Invidia EL headers and at least in regards of my butt dyno, can't really tell a difference. My Invidia's are the large primary version and as we speak I'm having the exhaust and intake sides of the heads, header, uppipe,turbo, tgv deletes, intake manifold all port matched for increased flow. Can't wait to see the difference.
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Old 02-21-2013, 12:09 PM   #15
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Great. Now I gotta swap all this out and wait another how many weeks for a tune
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Old 02-21-2013, 12:21 PM   #16
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Quote:
Originally Posted by booSTin-scoobs View Post
Great. Now I gotta swap all this out and wait another how many weeks for a tune
Slow down...Just leave it on and wait for the retune. It's not going to make a dramatic difference in terms of it being dangerous. Just a bit richer and slower spool. Just take it easy with the lead foot until you can get retuned and you'll be alright.
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Old 02-21-2013, 12:29 PM   #17
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Quote:
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Slow down...Just leave it on and wait for the retune. It's not going to make a dramatic difference in terms of it being dangerous. Just a bit richer and slower spool. Just take it easy with the lead foot until you can get retuned and you'll be alright.
How much slower spool you thinking? I can deal with a couple hundred Rpm's. I just don't wanna pay for a tune then have problems with the header down the road and need a retune. I want this re tune to go nice and smooth. I don't wanna lose power bc some chode sold me an eBay header if that's what it is
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Old 02-21-2013, 08:43 PM   #18
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+1 for running richer due to the efficiency of the headers versus stock manifolds.

so yes you're running richer afr's and thats why it "feels" slower.
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Old 02-21-2013, 08:48 PM   #19
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Is it worth it to buy the Perrin headers?
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Old 02-21-2013, 09:38 PM   #20
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It's worth it to buy a quality header over an ebay. Why? Ebay headers generally have junk fitment, crappy materials, and thinner walls that are easier to damage. Research THEN buy.
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Old 02-21-2013, 11:55 PM   #21
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I run the tomei elh and I love it but whatever header you choose you will increase the volume over stock. So you will lose some spool time.
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Old 02-22-2013, 08:24 PM   #22
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Quote:
Originally Posted by jaxscuby View Post
+1 for running richer due to the efficiency of the headers versus stock manifolds.

so yes you're running richer afr's and thats why it "feels" slower.
If you were more efficient I would suspect you would lean out, such as when you put on an EWG.

More efficient would mean more air throughput at current fueling=leaner.
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Old 02-22-2013, 08:48 PM   #23
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I bought a new uel tomei header. Talking to Keith at puretuning and he said with my setup deciding uel or el mainly depends on sound preference. So that was an easy pick
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Old 02-22-2013, 10:56 PM   #24
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if your so worried about spool ,then i'd go with a 16gxt .if your motor is not "built".
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Old 02-22-2013, 11:02 PM   #25
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Nah my 18g will spool nice I'm really not too worried about that.
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