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Old 05-18-2009, 12:53 PM   #26
TechMJ
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What about just a cross over pipe instead of getting a header at all.
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Old 05-18-2009, 04:28 PM   #27
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^gains will probably be negligible.
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Old 05-18-2009, 04:50 PM   #28
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My MadDad equal length headers made way more power than the stock headers.

It spooled faster and made more power EVERYWHERE especially in the tq and midrange. And the headers were the ONLY change. Both setups were Topspeed tuned.

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Old 05-18-2009, 08:02 PM   #29
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Thanks CoolRex I was hoping somebody would respond with some good info.

Last edited by TechMJ; 05-18-2009 at 11:16 PM.
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Old 05-19-2009, 05:22 AM   #30
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nice numbers!
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Old 05-25-2009, 04:16 AM   #31
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Quote:
Originally Posted by CoolRex View Post
My MadDad equal length headers made way more power than the stock headers.

It spooled faster and made more power EVERYWHERE especially in the tq and midrange. And the headers were the ONLY change. Both setups were Topspeed tuned.

7hp is WAY more power? Am I reading the chart wrong?
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Old 05-25-2009, 09:56 AM   #32
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The cool boxer rumble everyone is refering to is the product of a poorly designed exhaust system for a turbo car . or a na car for that matter . spacing the exhaust pulses equally not only creates a more efficent exhaust flow but the pulses are evenly spaced so when they come in contact with the turbine wheel its a smooth efficent rate of flow and thus a better way to have the exhaust run on any car . remember evenly spaced pulses also scavenge the combustion cylinder better and thus give a better response and more HP & TQ everywhere . not to mention the engine just runs smoother
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Old 05-25-2009, 10:21 AM   #33
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Quote:
Originally Posted by don_radeon View Post
7hp is WAY more power? Am I reading the chart wrong?
thats only comparing the difference at peak, theres a difference throughout the entire power band, in some areas more than others. more often than not mods pre turbo usually sacrifice bottom end for top end, or vice versa, in different ratios, but this is an improvement over all. therefore, further proving that equal is way more efficient in every area to unequal
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Old 05-25-2009, 10:30 AM   #34
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Quote:
Originally Posted by don_radeon View Post
7hp is WAY more power? Am I reading the chart wrong?
You are making the same mistake everyone makes....looking at peak numbers only. Look in the midrange....30-40 more tq and 20-30 more horsepower in the meat of the powerband FTW!
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Old 05-27-2009, 12:35 AM   #35
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how do you spool faster. It looks like it hits harder but way later. the stock seems to spool way quicker according to your chart.

anybody know the difference between MaddogEL, Tomei, and Perrin?

I am about to die deciding which header to get. Might even keep stock and just port them and coat. I want to have quicker spool if possible than stock on vfseries turbo.

Last edited by JASWRX; 05-27-2009 at 01:28 AM.
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Old 05-27-2009, 08:19 AM   #36
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Quote:
Originally Posted by JASWRX View Post
how do you spool faster. It looks like it hits harder but way later. the stock seems to spool way quicker according to your chart.

anybody know the difference between MaddogEL, Tomei, and Perrin?

I am about to die deciding which header to get. Might even keep stock and just port them and coat. I want to have quicker spool if possible than stock on vfseries turbo.
Difference between them in terms of?

The Tomei has the widest inner diameter uppipe of the three...I can tell you that much. More of a true EL design than @ least Perrin (not sure about the other one), comes with header wrap, and hasn't cracked in 13Kish miles and one nasty winter. Just saying.
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Old 05-27-2009, 01:03 PM   #37
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maybe I'm just old, but back in the good old days, the good headers where EL and the cheap ones where not. my thinking is choosing mods that make the most HP. to me the "boxer rumble" sounds like a misfire.
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Old 05-27-2009, 01:07 PM   #38
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maybe I'm just old, but back in the good old days, the good headers where EL and the cheap ones where not. my thinking is choosing mods that make the most HP. to me the "boxer rumble" sounds like a misfire.
Every older guy around here that has messed with cars used to always tell me my car was misfiring back when I was still on the stock headers .
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Old 05-27-2009, 01:28 PM   #39
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Quote:
Originally Posted by novacivic View Post
unequal length= a little more low end plus boxer rumbel

equal length= more power overall but no boxer rumble will sound more like every other 4 cyl minus the raspyness
incorrect...
boxter rumble comes from the firing order. i have an equil length and have the rumble.
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Old 05-27-2009, 01:28 PM   #40
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Quote:
Originally Posted by don_radeon View Post
7hp is WAY more power? Am I reading the chart wrong?
Yes your are reading it wrong
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Old 05-27-2009, 01:30 PM   #41
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incorrect...
boxter rumble comes from the firing order. i have an equil length and have the rumble.
Then you aren't truely equal length. Firing order is not the same as when the exhaust pulses hit the turbo.

In UEL headers the pulses are all staggered out hence the burble. In EL headers the pulses are all in line and in sequence. Think blowing a fan steady vs blow in hesitant pulses.
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Old 05-27-2009, 03:53 PM   #42
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I still do not see how you say you spool faster?
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Old 05-27-2009, 03:55 PM   #43
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I still do not see how you say you spool faster?
On the street it does. It spools faster and makes more power sooner. Period.
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Old 05-28-2009, 05:01 PM   #44
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does anybody have maddad's number. I have emailed them but have not heard back. I want to find out more about the EL header.
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Old 05-28-2009, 05:41 PM   #45
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I see a good gain around 5K-5.5K
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Old 05-28-2009, 06:15 PM   #46
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Drive an equal length header around town in your daily driving manner, and one without the EL...... the ndrive around town with the stock.... You'll notice the difference. Off boost response is much improved. Don't just look at WOT.

You should ask Big Al (Dynoflash) why he changed to equal lengths....at least that's what it sounds like during his 704whp pull..... I could be wrong. ....yes I am wrong... he uses twinscroll setup!!! Best of BOTH!!!

Last edited by FuJi K; 05-28-2009 at 06:21 PM.
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Old 05-29-2009, 02:57 AM   #47
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so you are saying off boost and below full torque, the Equal Length is much more drivable and feels more torque down low?
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Old 05-29-2009, 07:51 AM   #48
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Yes definately. But you also have to use a good setup. I liked the maddad's because the 1.6" piping. That's bigger than stock. The only downside is that you have to heat them up to get full power but header wrapping them solves that issue. Mine are ceramic coated but when I put the built 2.5L I will be header wrapping them.
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Old 05-29-2009, 08:30 AM   #49
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Quote:
Originally Posted by JASWRX View Post
I still do not see how you say you spool faster?
You honestly don't see how the light red line (after header torque) goes up on the chart before the light blue line (before header torque)? REALLY?!?!?! This indicates he's producing quite a bit more power earlier in the powerband. On a turbocharged car, that usually means it's spooling faster (torque has to come from somewhere).
Here's the graph one more time...

Quote:
Originally Posted by CoolRex View Post
If you don't see that, you either need to:

A: get your eyes checked
B: Hit yourself in the face with a hammer and give up
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Old 05-29-2009, 09:16 AM   #50
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^^^^Yes.

It's not insane faster spool but it's faster spool nontheless. Instead of a smooth pull back now the car literally snaps and plants your head back.

Also note that simply slapping headers on won't help much....I actually lost power because the AFR went from 11.0:1 to 10.2:1 in the upper rpms. But tuning for the headers made all the difference.
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