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Discussion Starter · #1 · (Edited)
Problem is that I have a really long, boggy turbo lag in my auto (yeah, I know...) that I'm trying to get rid of. I did the TC mod, but (in my case) it didn't really help if I just smash the pedal from idle.
So maybe a catless up-pipe or down-pipe combined with the TC will do the trick (I hope).

I've heard that both up and down pipes will help spool up, but is one more effective than the other?

I don't have the $$$ to purchase both, so which would you pick?
 

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Hmm... when doing the install, I *think* someone said you have to take off one to do the other anyway - I'd look into the install method - perhaps that could help you make your choice? I'm sure someone will drop by soon and know the answer to that one. :)

-snowcat
 

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Putting in a catless uppipe will allow you to start spooling at 2400-2500 rpm, rather than 3000. Trust me, I have an automatic too, and it made a huge difference. The downpipe will help as well, but I think the uppipe will make the biggest difference.

And, as snowcat says, you have to take off the stock downpipe anyway to put in an uppipe, so if you're short on money, get a nice cheap downpipe like an HKS and do them both at the same time. That'll be about $375 total (Godspeed uppipe + HKS downpipe for example) if you do the install yourself. If you get them installed at a shop, be prepared to pay another $150-300 for the install (depending on the shop of course).
 

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how much worry should this install cause you?

will any competent mechanic be able to do this correctly? or should they have plenty experience doing this exact swap?
are pipes still leaking? do any not leak?
is a gutted uppipe as good as an aftermarket?
 

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people did tests awhile ago and decided that gutted is same as aftermarket...
 

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I've driven WRXs with just the up pipe (including Vishnu's Stage 0) and with only a 3" catless turbo back exhaust system. You'll get and feel much faster spool with the turbo back, than say a VSO. No comparison.
 

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hmm, i'm sorry to hear that actually.
the last thing i want to do is change that exhaust. i love not hearing it, at all, especially at WOT...stealth is important to me.

exhaust to me should function and not be heard, the engine should provide all the music...at least on anything short of a V8.
mostly i just don't want tickets and the problems that come with having a loud exhaust. not from the volume, here in nyc, but going WOT on 1st ave is not something i would do with a miniature cannon hanging out of the rear.
 

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Go with the uppipe and get that damn pre-turbo cat outta there...
 

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On second thought, put the money towards a time machine so you can go back in time and get the manual.
 

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If you're on the cheap (I am eternally it seems;) ), here's what to do:

This requires a little work (to save on labor) but is not terribly difficult especially if you have some friends to help you with it. These three things will change the spool characteristics entirely - it will feel like a healthy NA V8 under the hood rather than a turbo'd 4 banger.

First: it's free, so do it now: gut the stock uppipe. Big performance gain for zero dollars and it still looks stock for the dealer.

Second: Get the APS turbo discharge outlet for $125. Take this to an exhaust shop and have the rest of the downpipe made up to the point where it connects with the main cat pipe (or, for a little more money go all the way back to the stock axleback section for a catless TXS stealthback sorta thing). Probably less than $175 for an exhaust shop to do the discharge outlet to main cat pipe connection.

A little nicer (albeit more expensive) alternative to this: get the TXS stealthback. I'm telling you, it sounds exactly like stock. There will be a noticable whistle coming from the turbo, but that is it, the volume and tone of the exhaust is the same as stock. You won't feel like a kid with a coffee can, trust me. That big TXS downpipe will really help spool, perhaps even more than gutting the uppipe. The stealthback is like $700 and you'll need a CEL fix from Pony Express Performance for another $20. Easy to install these parts.


Third: Get your ECU reflashed by Cobb for $400. Tell them what mods you have and get one off the shelf or spend some more money and get it dyno tuned. This will make it all run safe and right, and cut spool as well. For reference, just their reflash on your stock car will cut spool as much as an uppipe or a turboback exhaust will, but will give more power.

Final: if you gut the uppipe, get the APS discharge housing/custom downpipe, and get a Cobb reflash for all this you'll be at $700 tops, with a much smoother, faster spooling, and more powerful car. If $700 is still too much, cut the custom downpipe out of the equation; just gut the stock uppipe and get Cobb to reflash the ECU for a stock car w/uppipe. Best performance you can buy for 400 bucks, period.
 

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On the budget, gut the up pipe and buy a decent downpipe. Up pipe is essentially the same tube as OEM but without a cat, but the downpipe will have a different shape, like the bellmouth on the Scoobysport for example, in addition to the missing cat.
 

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nice website :)
 

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: : J-Lovin Moderator: :
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Dont gut out your stock uppipe. You drive a $25,000 car, dont cheap out on it. If money is a budget, just buy the HKS combo. HKS uppipe and downpipe. Or even the Gruppe S uppipe and HKS downpipe. Just remember, if you decide to go with a different turbo, the HKS wont work with it. Your gonna have to buy a different one. But if you dont plan on swapping soon. Dont worry about it.

Jason

P.S. For the HKS combo, give Garret a call from World One Performance. I was gonna do that combo but decided to go with Turbo XS.
 

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i added both the downpipe and the uppipe to my catback at the same time

5th gear spools up by 2550 if i floor it in 5th around 2300rpm

i also uninstalled my catback once afterwards and 5th gear spooled up by 2890 in the same situation

i forgot where it spools up in stock form though, and i've since re-installed the cat-back

numbers are exact cuz i can match them on AVC-R's graph plot :)
 

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also those numbers are the stock turbo spooling up to 1.0kg/cm^2, or 14.223psi
 

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PhreeZe said:
Dont gut out your stock uppipe. You drive a $25,000 car, dont cheap out on it. If money is a budget, just buy the HKS combo. HKS uppipe and downpipe. Or even the Gruppe S uppipe and HKS downpipe. Just remember, if you decide to go with a different turbo, the HKS wont work with it. Your gonna have to buy a different one. But if you dont plan on swapping soon. Dont worry about it.

Jason

P.S. For the HKS combo, give Garret a call from World One Performance. I was gonna do that combo but decided to go with Turbo XS.
LOL you told him not to cheap out then you told him how to cheap out on a downpipe!
 

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afpdl said:
LOL you told him not to cheap out then you told him how to cheap out on a downpipe!
The HKS is a great downpipe if you dont plan on swapping the turbo. Works perfectly well. So there is a reason to my suggestion.

Jason
 

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I didnt say it was a bad downpipe I just said it was cheaping out as far as downpipes go. Its design is basically that of the stocker just bigger diameter and no cats. A gutted uppipe is the same design of the stocker with not cat. The hks is made of questionable materials and has a uncertain life span as of now and is lacking a bellmouth or seperated wastegate desing. This does not make it a bad downpipe but it is still cheaping out.
 
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