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Sooooooooooo EURO
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Discussion Starter #1
long story short my old focus was totalled and I'm preparing to start modifying my next focus what I wanted to know was if running a 3" exhaust would harm myfocus or hurt It in some way?
I am planning to install a turbo in the next year hence my wanting to install a 3" exhaust now to save doing it later
Thanks
Brad
One last thing does anybody know where I can get a ready made 3" exhaust?
 

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tru-bendz.com ... and 3 inches isn't going to hurt your car. Jus you aren't going to be using it to its full abilities cuz your stock car isn't going to flow enough for a 3 inch. stock svts see good gains from a 3 inc so i'd imagine a reg zetec woulnd't be too bad
 

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i was looking into the tru bends but u have to have the hangers welded on. any one know of one that comes ready to bolt up?
 

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Sooooooooooo EURO
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Discussion Starter #5
and its expensive! good heavens batman i guess i'll be making my own just like i did for my old focus
 

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Focused Focus
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I dont know that i would run 3" on a standard Zetec unless its pretty well built. A svt works pretty well with it with no ill effects. The only issue i had was its fairly loud even with an extra resonator. On a side note, a friend of mine here at work that has a standard Zetec said to me one day, "isnt that kind of like throwing a hotdog down a hallway", lol.
 

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i have a 3in straight pipe on my zetec (installing turbo in a few weeks) and it is super loud and VERY raspy. then i put the svt cat on and its still pretty loud. but then again i am running 3 ins all the way back with no muffler.
 

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I dont know that i would run 3" on a standard Zetec unless its pretty well built. A svt works pretty well with it with no ill effects. The only issue i had was its fairly loud even with an extra resonator. On a side note, a friend of mine here at work that has a standard Zetec said to me one day, "isnt that kind of like throwing a hotdog down a hallway", lol.
why would u throw a hotdog down a hallway
your at school you throw pencils down the hallway
 

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what it be like
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i have a 3in straight pipe on my zetec (installing turbo in a few weeks) and it is super loud and VERY raspy. then i put the svt cat on and its still pretty loud. but then again i am running 3 ins all the way back with no muffler.
gawd that must sound horrible LOL..[joke]

and LOL about the hot dog down the hallway!! LOL....its true I think 3" is a lilttle much for any NA zetec
 

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i have a 3in straight pipe on my zetec (installing turbo in a few weeks) and it is super loud and VERY raspy. then i put the svt cat on and its still pretty loud. but then again i am running 3 ins all the way back with no muffler.
I would say be careful of an exhaust system that's TOO free-flowing -- I've had my 2003 ZX3 (non-SVT) for about a month, and it came equipped with the stock ZX3 exhaust manifold and flex pipe, followed by what I call a "******* cat-back": It had what looked like a 2-1/2" straight pipe back from the flex pipe, and a TINY little "muffler" (smaller than the stock ZX3 lunchbox, if you can believe it) at the back end.

Needless to say, this setup was PLENTY loud -- too loud for me, in fact. Not too loud to notice that I could hear what I believed to be valve clatter at higher RPMs, though. Nothing severe enough to worry about, and I'm not really familiar enough with Zetec engines to know if that's common, so I wasn't really worried about it.

Thankfully, I managed to locate a stock OEM SVT exhaust system (nice Ford parts, all stainless, low miles, still shiny, and embarrassingly cheap). I got the SVT exhaust installed yesterday and the transformation is amazing. The exhaust sounds great, and most surprising of all, now that things are MUCH quieter I can't detect ANY valve clatter at any RPM now. The engine also seems CONSIDERABLY more responsive across the entire RPM range.

Even more interesting, I have logged about 120 miles on the car since having the new exhaust installed and based on the movement of the fuel gauge it seems that I'm getting significantly better fuel economy on this tank of gas (and I've been doing lots of heel-and-toe shifting while enjoying the new exhaust note). I know the needle on the gas gauge alone is a poor tool for tracking fuel economy, but I typically reset my trip odometer every time I fill up, then do the "miles traveled divided by fuel required for the next fill-up" formula to calculate my mileage between fill-ups, so I'm pretty much aware at any given time of roughly what kind of fuel economy I'm getting based on the miles traveled since my last fill-up.

Anyway, my point is, I believe that the "******* cat-back" setup wasn't providing proper back pressure, thus leading to valve clatter (or perhaps detonation that I was interpreting as valve clatter?), occasionally sluggish throttle response, and poorer fuel economy.

Prior to installing the SVT exhaust, I had been experiencing fuel economy numbers ranging from 27 - 30 mpg, slightly lower than the 30 - 32 mpg I was enjoying with my previous car, a 1998 Saturn SL2 (equipped with a DOHC 2-liter 4-cylinder engine, not all that different than a Zetec). I plan to continue tracking my fuel economy numbers over the next few weeks and I will report back, but I think the bottom line is that my new yet "more restrictive" stock SVT exhaust system is actually MORE efficient overall than a more "open" system.

In the meantime, I would heartily recommend taking into account proper back-pressure considerations when opting for exhaust solutions for a normally-aspirated Zetec.
 

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Sooooooooooo EURO
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Discussion Starter #13
thanks for all the responses guys! i think i will stick with a 2.5" mandrel bent just like my old focus had.
as i've been doing research i think a 2.5" setup should be sufficient even with a turbo if i'm still running stock internals
 

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Sooooooooooo EURO
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Discussion Starter #15
if you have an eap you should be ok with a 3" though because the svt is a more built up motor..........at least thats how i understood b16sirs post
 

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from my expierence...too big of an exhaust pipe on a smaller 4 cyl motor isn't a great idea...you lose a lot of back pressure and it ends up hurting performance...stick with your 2.5" plan

also i assume you'll be running low boost on the stock motor so 2.5 should be good for that

just my .02
 

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zetec 2 duratec swap
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boosted i think 3 inch is ok. if you are running a lot of boost it will be just fine. but for something low 2.5 or 2.75 might be what you need. hks makes a catback that would be great on your car and still be rather quiet compared to mbrp focussport or pretty much any system out there.
 

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YOu will gain both HP and TQ across the entire RPM range with 3" exhaust... this has been covered MANY times and yes there are dynos on here to look at.
 

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Sooooooooooo EURO
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Discussion Starter #19
YOu will gain both HP and TQ across the entire RPM range with 3" exhaust... this has been covered MANY times and yes there are dynos on here to look at.
i know i would definately gain hp/tq when boosted but it could be over a year before i do! and in the time before i get boosted i'll probably put 30k more miles on the car so i dont want to wreck teh motor before i boost!
 

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from my expierence...too big of an exhaust pipe on a smaller 4 cyl motor isn't a great idea...you lose a lot of back pressure and it ends up hurting performance...stick with your 2.5" plan
I believe that does not apply to our engines because of their design.
 
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