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Trump 2016
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stock size 2/25 was wondering most aftermarket are the same just wondering why it wouldnt be 2 and a half
 

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stock is more 2.26ish. some aftermarket are 2.5 even 3. I would say the 2.25 ones are remarked zx3 ones
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2.25 is more than sufficient to support the power of the stock SVT. You don't gain anything by going bigger unless you're restricted to begin with, if anything it hurts performance.
 

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Borla is 2.5"

You don't lose power by going larger on the SVTf.
 

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You don't lose power by going larger on the SVTf.
At a certain point yes, you will. The SVTf is no different than any other vehicle out there in that it can't deny the laws of thermo/heat transfer. Properly sized exhaust allows the exhaust gases to maintain a particular temperature which subsequently allows for optimal flow.
 

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At a certain point yes, you will. The SVTf is no different than any other vehicle out there in that it can't deny the laws of thermo/heat transfer. Properly sized exhaust allows the exhaust gases to maintain a particular temperature which subsequently allows for optimal flow.
You can put a 2 foot wide exhaust after the cat if you wanted to and it wouldn't make any difference. It's already been dyno proven that you don't lose any power with a 2.5" or 3" exhaust; feel free to dyno test anything bigger.
 

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You can put a 2 foot wide exhaust after the cat if you wanted to and it wouldn't make any difference. It's already been dyno proven that you don't lose any power with a 2.5" or 3" exhaust; feel free to dyno test anything bigger.
I guess I should've clarified. I wasn't talking specifically just about a cat-back. I would agree with what you said above. An exhaust system is more than just a cat-back though.
 

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If we dive into theory, we're wandering beyond the point of this thread. Pasta's question is about exhaust kits, which are cat-backs (actually flex-backs).

As an aside, it's also been proven that 2.5" off-road pipes don't lose any power, either.
 

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If we dive into theory, we're wandering beyond the point of this thread. Pasta's question is about exhaust kits, which are cat-backs (actually flex-backs).
Agreed, I didn't mean to get this far off-track. My initial post was just to point out that 2.25" is plenty sufficient for the stock SVT.

As an aside, it's also been proven that 2.5" off-road pipes don't lose any power, either.
That's still not the entire system.
 

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I mean even with a 2.5" exhaust and 2.5" flex-pipe paired with the off-road pipe, there's still no loss in power.
 

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I know what you meant, my statement still stands...that's not the ENTIRE exhaust system. And going from 2.25" to 2.5" isn't what I would consider a substantial size increase
 

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Again, you have strayed beyond the point of this thread; nobody is talking about the header. Your original post:

2.25 is more than sufficient to support the power of the stock SVT. You don't gain anything by going bigger unless you're restricted to begin with, if anything it hurts performance.
Clearly you understood at the beginning that this discussion was about exhaust diameter by pointing out the 2.25" measurement, but made a baseless claim that going larger hurts performance. I am pointing out that increasing the diameter to 2.5" does not hurt performance at all on the SVTf, based on dyno tests. There have been claims that increasing everything after the header to 3" doesn't hurt performance either (and actually increases it), but the one dyno that shows this has been disputed for years with limited information.

If you want to discuss the header and theoretical exhaust flow characteristics, please either start a new thread or research the many, many threads that have already been posted about it over the past nearly ten years. The OP basically asked why there weren't many 2.5" exhaust kits, implying that he wanted one, and apparently I'm the only one who actually answered his question. I'm not trying to offend you or anything, just setting the facts straight and trying to keep this thread on topic so it remains helpful.
 

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Cayse. He doesn't understand lol. This has been beat to death on the dynos. Research the sticky we know what we know cause its been done before.
 

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Again, you have strayed beyond the point of this thread; nobody is talking about the header. Your original post:

Clearly you understood at the beginning that this discussion was about exhaust diameter by pointing out the 2.25" measurement, but made a baseless claim that going larger hurts performance. I am pointing out that increasing the diameter to 2.5" does not hurt performance at all on the SVTf, based on dyno tests. There have been claims that increasing everything after the header to 3" doesn't hurt performance either (and actually increases it), but the one dyno that shows this has been disputed for years with limited information.

If you want to discuss the header and theoretical exhaust flow characteristics, please either start a new thread or research the many, many threads that have already been posted about it over the past nearly ten years. The OP basically asked why there weren't many 2.5" exhaust kits, implying that he wanted one, and apparently I'm the only one who actually answered his question. I'm not trying to offend you or anything, just setting the facts straight and trying to keep this thread on topic so it remains helpful.
Oh for [:)][:)][:)][:)]'s sake. You know god-damn well what I was getting at, you're just the type of [:)][:)][:)][:)][:)][:)][:)] that can't ever be wrong. You're leading this thread off topic just as much as I am. I NEVER said that going to 2.5", even 3" was going to hurt performance. I said that going TOO BIG can. I don't have the data to make that call of what is too big, I was just stating that 2.25" is sufficient for the stock SVTf.
 

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I have a 63mm zhorst from the header with a decat pipe , it gave me about 10 bhp increase in power
 

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I have a 63mm zhorst from the header with a decat pipe , it gave me about 10 bhp increase in power
Nice, that decat pipe does give a good bump in power. Is "zhorst" a brand name or another word for exhaust? I've seen the word used in European forums a few times.
 

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Ooooops sorry me bad , exhaust lol and its a custom built 2 box setup , ok that's the only a/m. Accessory we. Fet with no hastle , guys are big into the st 225 and the fiesta st 150 , the volvo powered ford
 
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