Reference to my recently posted topic on choosing the best performing CAI.. i'm now curious what exhaust system to go for.

forget the sound and looks.. but between headers and an exhaust system.. what's the best exhaust setup proven to produce the highest rwhp/torque gains?

LEO_06GT posted a
link to a great article on mustang50 magazine, that did a roundup test of all commonly found CAI and posted their actual gains based on independent dyno tests..

has anyone found a similar exhaust comparison article?

many thanks..

 

well, forsure Long Tube headers, an off road pipe, and straigh thru mufflers are what you are looking for. As to which ones..... we have found that all the axel backs pretty much net the same power, pick one that you like sound/looks wise. In theory X pipes flow slightly better than H pipes, but the difference is so small, again, pick the one that sounds better to you. I personally am not a fan of the X pipe sound. as for headers, if you are going to stay N/A than the smaller diameter tubes are better, but if you go with a supercharger, the larger diameter tubes are better. As for which header brand produces the most gain..... I have not done enough research on that.

Hope that helps!!

 

Corsa say's 13 more horsepower and 9.5 lb-ft. I don't know about the frpp/borla's but man they sound amazing!

 

I think that you get about the same from all of the main characters in the exhaust circuit (borla, corsa, GMS, flowmasters, etc). The Headers are best at the long tube and if your going to do the SC/Turbo, you would probably want to up it to a 3" pipe over the standard 2 1/2" pipes. Every car reacts differently to change so basically buy what you like and those combos should be good enough not to make you rethink your decision. Not much help on a decision which is what everybody would like but if there was one combo that was that much better, than everybody would use it. Try something like Hooker long tubes, Dr. Gas x pipe and a set of Borla's, etc. You won't be able to hear anything but rumble and it should give you as much as you can expect.

 

mufflers do almost zilch.

-Dan

 

Depends on what you want and how much you want to spend. MM& FF did a shoot out a year ago with shorty headers, X pipes and mufflers. Most of those offered minimal gains, just sound differences. You said you want HP and torque. Long Tubes are the real deal. X pipe or H pipe will affect your sound mostly. So will the mufflers. I found package deals with Stainless works and Kooks and/or JDM. Most ran between 1400 to 1500ish (shipping charges ranged from free to charges). I found SLP w/ xpipe at 1029.00 free shipping. That was about 400 to 500 cheaper. Most after cat mufflers will run you from less than 300 for flowmasters to close to 500 for borlas, magnaflows, etc. I got my SLP from lmperformance.com they were close out on sale. They were good quality and fit with out incident. I am sure kooks, SW and others will also.

I have not dyno'd mine but others on the forums claim 22 or so rwhp for a set of long tubes, I think most will perform the same.

 

If you're going turbo, don't waste your money on LTs. You'll just have to sell them used later (unless you do something like the STS turbo). And I have yet to see any evidence that a 3" system will do any better than the 2.5" system on a small engine like our 4.6L... even with a power adder. Unless you have a fire breathing big block, I would spend that money elsewhere.

 

so based on your input, and my reading on wikipedia i should be looking for after market headers first

i've seen mixed reactions here.. some say long tubes, some say shorty headers.
again, to me the sound is the last thing i will be considering, as believe it or not, i'm happy with the stock exhaust sound, and wouldn't care to have something louder.

so performance wise, starting with the headers, which way to go.. long tubes or shorty headers?
i'm assuming the headers (both short and long) will connect the cylinder exhaust ports to the catalytic converter.. then the cat-back/axle back exhaust would go from the cat back.. is that correct?
i read alot about the JBA's but then again my knowledge here is pretty limited to judge yet.

so what's an offroad pipe? does any of the suggestions above include removing the catalytic converters? cuz i wanna keep the car street legal by all means..

sorry for the million questions. and thanks again to everyone that took the time to reply!

 

The one already on your car.

Be sure and check out the thread about headers melting the battery tray.

I love the factory exhaust, honestly. I've already been through my loud exhaust phase I guess.

 

In my opinion (and many others), shorties will give you minimal power gains, but will allow the use of the stock cats. LTs will provide more power gains, but will not work with the factory cats.

 

i'm on JBA's site checking out LTs. and they seem to be the way to go, however they do mention that these are not street legal :S
are all Longtubes made for off-road use?

 

Do they have any emissions or noise requirements in Dubai?

 

Noise, no.. although anyone could complain and cause me a headache with the cops.
however, all cars have to pass an annual checkup prior to the renewal of the registration, which checks tires and emissions.
not sure about the actual permissible emission levels though.