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Discussion Starter · #1 ·
Right now I'm stock but want to do these things eventually in order:
cold air intake, base/cable bushings, regulator bypass, intercooler res delete, oil catch can, custom catback exhaust, tork stage 0 tune (after warranty), lighter crank pulley maybe and thats about it

I don't want the car to be really loud. I don't mind some deep and a little drone but no rasp! I want the best flow for my goals above:

1. Would the performance with the tune outweigh the loudness that header would give me?
2. Would a high flow downpipe with mini cat be of good to me?
3. Which cat should i remove? or resonator?
4. With my goals and regards to sound and the tune, what do you guys think?

Correct me if I'm wrong, the order from front to back of the entire exhaust system.

header - downpipe(cat) - resonator - actual cat - catback ? A picture of the underside front to back would be helpful.

Also what's considered the mid-pipe?
 

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We don't have a header. We have a turbo manifold and if you want that changed its custom. Best thing to do is get rid of the second cat and the rear muffler first. Then get a catless or catted dp.

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Discussion Starter · #3 ·
oh okay I'm still new to cars with turbo and I haven't really analyzed what goes on with the turbo and under the car yet.
I don't really want to custom the turbo manifold, but I did see a catted downpipe in the for sale section so it got me wondering.

I can understand changing out the exhaust before going extra further like the dp so it making me think the stage 0 tune doesn't really need or make good use of the dp upgrade unless it was for more power right?

i've seen pics of the catback on our cars, but about how far after the flanges is the 2nd cat?
i read punching it out makes the sound little more harsh? so i was thinking of getting a highflow maybe to replace it?
i was thinking of getting pipes off summit and have a shop weld it up with mandrel bends.

I was really trying to understand what is really the bottleneck(s) with air because it seemed like people say the muffler was really restricting and then others seem to feel the cats play a huge part so..
 

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oh okay I'm still new to cars with turbo and I haven't really analyzed what goes on with the turbo and under the car yet.
I don't really want to custom the turbo manifold, but I did see a catted downpipe in the for sale section so it got me wondering.

I can understand changing out the exhaust before going extra further like the dp so it making me think the stage 0 tune doesn't really need or make good use of the dp upgrade unless it was for more power right?

i've seen pics of the catback on our cars, but about how far after the flanges is the 2nd cat?
i read punching it out makes the sound little more harsh? so i was thinking of getting a highflow maybe to replace it?
i was thinking of getting pipes off summit and have a shop weld it up with mandrel bends.

I was really trying to understand what is really the bottleneck(s) with air because it seemed like people say the muffler was really restricting and then others seem to feel the cats play a huge part so..
I'm new to this car but not turbo's... I saw else where that round piece right past the flange is the 2nd cat and gutting it make it a little louder but not much and not raspy, I think I'll look into that too, don't worry about a high flow version for the 2nd cat, I'd just gut it from all I've gathered... But downpipes are usually one of the most restrictive parts too, a straight "test pipe" is what most real turbo guys use but there is also one available for ours with a HFC (High Flow Cat) for guys like me that want to run at least semi-clean... anyway, gutting 2nd cat and an intake sounds like a great place to start and an intake shouldn't void your engine warranty, they have to PROVE that just some extra air flow caused or contributed to the problem... Anyway that's as far as initial power gains. it sounds like we should worry more about handling and engine/trans mount issues as well. Also, depending if you have an auto or manual, the cost for a spare ECU might be worth a tune as well, especially on top of those basic mods.
 

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Discussion Starter · #5 ·
okay with intake and the 2nd cat/muffler deleted, how much louder will a highflow downpipe make the car?
i plan to just flash my existing ecu after 60000 miles. im at 20000 so far.

also what diameter is the exhaust from the catback flange? when buying the summit pipes to custom at a shop what diameter is best?
 

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Right now I'm stock but want to do these things eventually in order:
cold air intake, base/cable bushings, regulator bypass, intercooler res delete, oil catch can, custom catback exhaust, tork stage 0 tune (after warranty), lighter crank pulley maybe and thats about it

I don't want the car to be really loud. I don't mind some deep and a little drone but no rasp! I want the best flow for my goals above:

1. Would the performance with the tune outweigh the loudness that header would give me?
2. Would a high flow downpipe with mini cat be of good to me?
3. Which cat should i remove? or resonator?
4. With my goals and regards to sound and the tune, what do you guys think?

Correct me if I'm wrong, the order from front to back of the entire exhaust system.

header - downpipe(cat) - resonator - actual cat - catback ? A picture of the underside front to back would be helpful.

Also what's considered the mid-pipe?
Alright ill try to answer everything in order, if I miss anything, let me know.

1 Turbocharged engines don't necessarily have headers, they have something similar, known by a few different names, exhaust manifold, turbo manifold, turbofold the designs on the Forte Turbos utilize a turbofold in which the hot side (exhaust side) is built in to the manifold. Basically the way to replace the manifold would be doing a big turbo kit. So I am assuming you are asking about the downpipe, which depending on exhaust configuration, the noise you will get even from a catless downpipe can be minimal. Though it can change the sound significantly, with a stock exhaust sound change will not crazy different. Just a bit deeper. Hi flow cat will be even less loud. In my opinion, it is well worth it for the gains, Though if you plan on going with a stage 0 I would just go with our hi flow catted option.

2 I guess I summed this up in my last sentence on number 1, but to reiterate, I would just go hi flow cat unless you plan on stepping up beyond a stage 0 at any point. If you play on staying with a stage 0 a catless downpipe will not be needed to gain any extra power.

3 We have found that the secondary cat is actually a huge restriction. So based on performance, before anything else I would begin with removing that. If you want more sound go with the down pipe, if from there you still want more, then I would look at removing resonators or mufflers.

4 Im not fully understanding the question, I think that with a stage 0 tune, intake, and downpipe, you will be beyond satisfied, and it will feel like a brand new car.

Manifold-Downpipe-midpipe-exhaust

manifold is bolted directly to the head, and also houses the turbo, that the downpipe connects to, mid pipes can be a bit tricky, as some are only a foot or so in length, others can go all the way to the rear of the car essentially meeting to what would be the axle back, essentially cat back is in reference to what would bolt to either the downpipe in a turbocharged car, or a header in a naturally aspirated car. These meanings get a little jumbled up depending on what markets you talk to and what companies support them. I basically would just say that the cat-back is anything from the downpipe back.

Tyson
 
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Discussion Starter · #7 ·
Alright ill try to answer everything in order, if I miss anything, let me know.

1 Turbocharged engines don't necessarily have headers, they have something similar, known by a few different names, exhaust manifold, turbo manifold, turbofold the designs on the Forte Turbos utilize a turbofold in which the hot side (exhaust side) is built in to the manifold. Basically the way to replace the manifold would be doing a big turbo kit. So I am assuming you are asking about the downpipe, which depending on exhaust configuration, the noise you will get even from a catless downpipe can be minimal. Though it can change the sound significantly, with a stock exhaust sound change will not crazy different. Just a bit deeper. Hi flow cat will be even less loud. In my opinion, it is well worth it for the gains, Though if you plan on going with a stage 0 I would just go with our hi flow catted option.

2 I guess I summed this up in my last sentence on number 1, but to reiterate, I would just go hi flow cat unless you plan on stepping up beyond a stage 0 at any point. If you play on staying with a stage 0 a catless downpipe will not be needed to gain any extra power.

3 We have found that the secondary cat is actually a huge restriction. So based on performance, before anything else I would begin with removing that. If you want more sound go with the down pipe, if from there you still want more, then I would look at removing resonators or mufflers.

4 Im not fully understanding the question, I think that with a stage 0 tune, intake, and downpipe, you will be beyond satisfied, and it will feel like a brand new car.

Manifold-Downpipe-midpipe-exhaust

manifold is bolted directly to the head, and also houses the turbo, that the downpipe connects to, mid pipes can be a bit tricky, as some are only a foot or so in length, others can go all the way to the rear of the car essentially meeting to what would be the axle back, essentially cat back is in reference to what would bolt to either the downpipe in a turbocharged car, or a header in a naturally aspirated car. These meanings get a little jumbled up depending on what markets you talk to and what companies support them. I basically would just say that the cat-back is anything from the downpipe back.

Tyson
in response to your responses:

1. i only looked at stage 0 and it seemed like a good fit for me but maybe i need to find out more about the other stages first. if i went with a downpipe, i probably would like it catted to minimize the sound for sure if it can be that bad. i really dont want the car to sound like a camero roaring down the road.

2. so if i want stage 1 and up is a catless downpipe needed or better? catted vs catless downpipe noise level, is it that much louder?

3. people have said the muffler is a huge restriction too but i don't know compared to the 2nd cat. are they both about the same with restrictions? maybe the muffler is more sound and lesser flow difference when deleted and the 2nd cat is less sound but more flow when deleted?

4. i noticed you didn't mention muffler delete or catback exhaust. perhaps its not as necessary unless i want more sound? i just always thought mufflers slow down the flow too where it was imperative to change them out for better performance.

Thank you for spending extra time to explain things!
 
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