[anantnehru]

Ok, so after going through a few threads on Free Flow Exhausts and K&N Air Filters, I have understood the following - please correct if I am wrong. I am also including in this a few questions, which hopefully someone will answer, since I'm completely alien to the performance aspect of a car.

1. FFEs change your entire exhaust system, and add to your performance. They can also help you FE but in most cases doesnt because gun the engine to hear the sound.
2. K&N Air Filters alongwith FFEs are the best combination for a performance upgrade. From what I remember a long time ago, there are a few types of K&Ns; which is best choice and for how much?
Also, do you need a Cold Air Intake with a K&N? Or is that another addon?
3. End cans improve the sound of the engine making it deeper but do not have FE or performance value adds as such. Any particular brand and what price range? (For an Sx4)
4. Installation of your FFE will rid the engine of the catalytic convertor. Not too good for the environment, I have read someone's post in this thread who has a catback system. What is the further cost involved for a set up like this?
5. Headers. Not sure if they're related to the FFE, but read that they also can add to performance(??). Whats the benefit of these and again, costs involved?

Oh and I dontknow if this was the proper thread for the above, but it was the most active out of all the FFE threads.

[Strangerintown]

Have never run a FFE on my cars but have tried to answer what little I know based on my understanding, appended in bold below.

Originally Posted by anantnehru

1. FFEs change your entire exhaust system, and add to your performance. They can also help you FE but in most cases doesnt because gun the engine to hear the sound. Absolutely right
2. K&N Air Filters alongwith FFEs are the best combination for a performance upgrade. From what I remember a long time ago, there are a few types of K&Ns; which is best choice and for how much? K&Ns and FFEs are the easiest and most painfree way of getting additional performance in most cases. The best mods will depend on your budget and how much you want to risk tampering with the engine.
Also, do you need a Cold Air Intake with a K&N? Or is that another addon? A CAI is good to have but not a necessity.
3. End cans improve the sound of the engine making it deeper but do not have FE or performance value adds as such. Any particular brand and what price range? (For an Sx4) End cans are only for sound and appearance. Not sure about brands. I know Automech makes end cans too - not sure about availability for SX4.
4. Installation of your FFE will rid the engine of the catalytic convertor. Not too good for the environment, I have read someone's post in this thread who has a catback system. What is the further cost involved for a set up like this?
5. Headers. Not sure if they're related to the FFE, but read that they also can add to performance(??). Whats the benefit of these and again, costs involved?

[GTO]

Also, do you need a Cold Air Intake with a K&N? Or is that another addon? A CAI is good to have but not a necessity.

Only a conical filter requires a well-designed CAI system. The stock replacement filter doesn't as it will use your existing routing.

4. Installation of your FFE will rid the engine of the catalytic convertor. Not too good for the environment, I have read someone's post in this thread who has a catback system. What is the further cost involved for a set up like this?

A catback simply means "everything behind the catalytic converter". It will be cheaper than a full free flow exhaust that includes new headers.

5. Headers. Not sure if they're related to the FFE, but read that they also can add to performance(??). Whats the benefit of these and again, costs involved?

Effective header design is most crucial to a performance enhancing custom exhaust.

[anantnehru]

Originally Posted by GTO

Only a conical filter requires a well-designed CAI system. The stock replacement filter doesn't as it will use your existing routing.



A catback simply means "everything behind the catalytic converter". It will be cheaper than a full free flow exhaust that includes new headers.



Effective header design is most crucial to a performance enhancing custom exhaust.

Cool thanks!
But what are the different types of filters available? I've pretty much only seen conical filters.
So a catback is the same as a FFE? As in, ok you retain you convertor but is there any difference - performance wise?
Header most crucial, ok, but necessary?
Also, thanks strangerintown!

[ankitahuja]

Can someone give a detailed explanation on what exactly is the role of the Mid Muffler AND Expansion Chamber in an FFE set up.

Is one of them used in place of the other or how does it work?

[naveen.kk]

Sorry for a question over the another one. I have Palio 1.6 with Custom FFE. I use its most in city, than on highways. I feel low end is ok, and mid range is fine, and high end is best, and grunt is too loud. I am looking to change it a little to get gains on low end, and make it sound quiet at low rpms atleast.

Can any one suggest me anything?

I was adviced to replace the end can for reducing the grunt. But, what will help in gaining more low end?

Thanks in advance.

[nc1bad]

Hi, been following this thread for quite some time,i have installed automech exhaust in my OHC 1.5 , the note etc is satifactory,but the build quality is bad. I have attached couple of pics showing total break-off of the silencer can and the pipe. Its been fixed now but i still have some rattling sound at a specific rpm.

[vikram_d]

Wow that is bad. Rattling sound at a specific RPM generally indicate a problem with the rubber mounts that hold the exhaust system. Have all the rubber mounts checked.

[anantnehru]

Ok, so since there havent been too many replies I started looking out for performance exhausts. I came across one, but its specs are all greek to me. So if anyone could tell me whether this would suit the Sx4 or not, I would be extremely grateful! Also, if it doesnt suit the Sx4 what specs should I look out for and if Im being painful, again - please feel free to let me know

(Or can you just plonk on any exhaust onto any car without any issues?)

Muffler, Super Turbo, 2 1/2 in. Inlet/2 1/2 in. Outlet, Steel, Aluminized, Each

Case Length (in) 14.000 in.
Case Shape Oval
Inlet Diameter (in) 2.500 in.
Inlet Location Offset
Inlet Quantity Single
Internal Construction Turbo-style
Muffler Finish Aluminized
Muffler Material Steel
Notes Inlet and exit are out the same side.
Outlet Diameter (in) 2.500 in.
Outlet Location Offset
Outlet Quantity Single
Outlet Style Standard, without tip
Overall Length (in) 15.500 in.
Thickness (in) 4.250 in.
Width (in) 9.750 in.

[ankitahuja]

@Anant - What you are talking about is only the exhaust / end can / muffler and not a complete Free Flow Exhaust system (which includes headers, mid muffler, mid pipes and then the end muffler).

Generally, the end cans are universal and can be fitted to any car, but choosing the right design (correct inlet diameter and outlet etc) can sometimes be useful. Changing only the muffler would not make any difference unless your OE muffler is 'highly restrictive', else it will be only change in sound to a sporty one.

In simple terms - A FFE looks exactly the same as a stock exhaust system, only difference is in the diameter of the pipes used and tweaks in the header design (molds of the pipes) and sometimes the material of the piping.

See pictures:

END CAN Only:



Free Flow Exhaust System:
Headers



With Cat Con bypass



Complete with end can (this is the stock exhaust system)

[anantnehru]

Ooohk..Thank for the heads up.
So the one I've mentioned would basically suit any car? So I dont have to keep in mind certain specifications right?

[ankitahuja]

That's not entirely true. The muffler you choose should have the same or at least 0.5" bigger inlet pipe than your existing mid pipes. Check that the muffler is not restrictive (see if you can see straight through the muffler to the other end).
Sound will depend on the overall diameter/length and amount of glass-wool used to make a muffler.

The specs you've mentioned state 2.5" inlet and outlet. For it to look good, you might want one with at least a 3" outlet/tip for those good looks?

"Notes Inlet and exit are out the same side" - This surely has left me confused! Post pics / link if you can.

Also, see this thread - http://www.team-bhp.com/forum/collec...w-exhaust.html

[nc1bad]

thanks shall get it checked

Originally Posted by vikram_d

Wow that is bad. Rattling sound at a specific RPM generally indicate a problem with the rubber mounts that hold the exhaust system. Have all the rubber mounts checked.

[abhik]

Originally Posted by ankitahuja

Can someone give a detailed explanation on what exactly is the role of the Mid Muffler AND Expansion Chamber in an FFE set up.

Is one of them used in place of the other or how does it work?

A Mid-Muffler is mainly installed to modulate sound. It consists of meshes and fins through which sound reflects and produces a note which is desired by the muffler designer. One can regulate the pitch of the exhaust note i.e sharpness and bass and also its loudness. No/little dampening takes place here. The main dampening of sound is done by the end-can which consists of glass wool etc to dampen sound.
The mid-muffler does however contribute to exhaust restriction.

An Expansion Chamber, ideally meant for 2 stroke engines, is meant to increase performance. In simple terms, it works by accumulating exhaust gasses in the enlarged section of the chamber and pushing it out with force with the gasses from the next cycle.

The first pic shows Expansion Chambers and the next shows a Mid-Muffler.

[anantnehru]

Originally Posted by anantnehru

Muffler, Super Turbo, 2 1/2 in. Inlet/2 1/2 in. Outlet, Steel, Aluminized, Each

Case Length (in) 14.000 in.
Case Shape Oval
Inlet Diameter (in) 2.500 in.
Inlet Location Offset
Inlet Quantity Single
Internal Construction Turbo-style
Muffler Finish Aluminized
Muffler Material Steel
Notes Inlet and exit are out the same side.
Outlet Diameter (in) 2.500 in.
Outlet Location Offset
Outlet Quantity Single
Outlet Style Standard, without tip
Overall Length (in) 15.500 in.
Thickness (in) 4.250 in.
Width (in) 9.750 in.

Well here are the same specs with a picture of the end can.