Exhaust help

[Gotian]

Thanks for helping me out to buy tires, I solved that problem. Im not really looking for an exhaust, im just curious about some things since i am not very knowledgable with exhausts and it doesnt hurt to learn more.

I wanted to know what the lightest metal an exhaust can be made out of and does the material have any affect on gains?

Also Would having no muffler affect anything besides the noise?

Obviously these questions are more for anyone with F/I experience so share some knowledge

[BLU CIVIC]

i doubt having a exhaust made out of light weight material will affect it's performance since the air flow will encounter the same resistance...it's the type of exhaust that makes a difference...the only thing you'd gain with a lightweight exhaust is weight reduction

[Gotian]

Originally Posted by BLU CIVIC

i doubt having a exhaust made out of light weight material will affect it's performance since the air flow will encounter the same resistance...it's the type of exhaust that makes a difference...the only thing you'd gain with a lightweight exhaust is weight reduction

well that i already knew, how about the muffler part? does it affect performance to go without a muffler?

[turtlecrxsi]

A muffler is just that... a muffler... it muffles sound so you don't hear the resonance of the engine's output. I've always heard that on FI cars no exhaust at all is best.

The lightest material would be titanium. But like Blu said it would only really serve for weight reduction. I only have seen one person go the titanium route. That was Emil from Slovenia with his low 13 second 4g civic. He had an exhaust custom made by DeVito that was titanium with mandrel bends with a removable muffler section for track days. Stainless steel would be be high quality and probably outlast the car. Alumnized piping works well and can be found at most muffler shops if you decide to go the custom route.

[Gotian]

cools, i know for my car if i was to do an exhaust it would be a turbo back exhaust and i would probably get rid of the cat, besides the whole it's bad for the environment thing is there a difference in power between no cat and a hi-flow cat? Or is the difference very minimal that it wouldnt matter either way?

[blackstang04]

No cats or mufflers = huge loss of backpressure. I wouldn't be surprised if you experienced a loss in power by doing something like that. Like the other guy mentioned, Titanium would be the lightest setup, but it would be a hell of a lot more expensive than a normal metal/stainless steel exhaust. The weight savings would be minimal too. You'd get more weight reduction out of removing your spare tire and jack than you would a lightweight exhaust.

My $.002.

[Chiquae07]

why not instead of all the exhaust being done, why not just an exhaust cut out? the least amount of backpressure, and its like running no muffler at all. you can place it before the cat converter as well. they have ones that come with electric openers(waste of cash since it'll be ruined by exhaust fumes), ones that come with like a pull-push switch to open and close it, or the manually opened one, with ususally 3 bolts, 3 washers, a gasket, and a piece of metal to keep the cutout from leaking.

you could always run a test pipe if you'd like to, until the emissions day. thats what most people i know do. but its your call.

[-The Stig-]

Is this for the Rotary or the 1.8T? Cause I'd be worried that if you take away back pressure from the Renesis, it'd have almost no torque at all, they aren't torque machines as it is... might actually slow the car down.

[Chiquae07]

if anything, i'd say its the jetta, as he is speaking about if you had F/I. but yet again, he might be planning something for the renesis. who knows. i remember him saying he wanted to to something to that engine, but im not too sure if he wants that released. can't remember that far back.

[VR43000GT]

Check around for different exhaust made for your car and look up the specs made for them including wait. I'm still trying to get my carbon fiber exhaust...........................for my bike.

[Igovert500]

If you are talking about a car with a turbo, the turbo probably already provides more than adequate backpressure. So you don't have to worry about going too wide. On NA cars, that is a concern, with turbos...not so much. That is why you hear people say hte best exhuast on a turbo car is none at all. What you want is the freest flowing exhaust you can get your hands on. Cats, resonators, etc all are restrictions in some way or another...they are disrupting flow and this robs you of power. They keep the car quieter adn the cats are good for hte environment, but they steal some horsepower. If you have emissions I suggest swapping in a testpipe instead. A highflow cat is still going to be a restriction, even though it is less of one than a stock cat.

If you aren't concerned with noise and the cops wont be either, I'd say go for a full 3" mandrel bent single shot exhaust. Custom is cheap. But check out different exhausts for your car and see what sizes they are offered in. They will probably be a bit smaller. Also, ask people who own your car, where the biggest restrictions in your exhaust is. Each car has it's own spots that need the most improvement. For instance, my stock catback is fine, but my stock downpipe and cats blow...so they were my first focus.

Just keep in mind, the more you remove and hte more you widen it, hte louder its gonna get. So if a really loud exhaust is gonna bother you, your family, neighbors, or hte local police, a cutout maybe the route you wanna go. Power when you want it, back to normal when you want to be low-pro.

Also, as far as material, I'd just use stainless steel. It's cheap and doesn't weigh that much. Weight really only becomes an issue when people make dual exhausts and such for looks and double the weight of their exhaust...negating any gains they just got in power. I think htere are always easier ways to save weight, than paying 3x as much to save 15lbs in piping. just my .02

[Gotian]

thanks guys, i am talking about the jetta cause the stock exhaust for the rx-8 is pretty much maxed out and the most anyone has gotten for gains on the 8 is about 3hp.

just by looking at the exhaust on the jetta you can see how restrictive it is, its probably a 1 1/2" pipe all the way to the muffler and the muffler tips look like two floppy guy parts. The stock exhaust itself is very heavy especially the muffler and people have saved at least 20 pounds by going stainless steel. Also there is no emmissions testing in florida, that was stopped years and years ago. And it would have to be a turbo back exhaust or else it is pretty much pointless to do an exhaust. My turbo runs off the exhaust and most people who have done a turbo back have freed up alot of torque becuase the turbo is able to spool up much quicker and it also allows the turbo to boost usually a pound or two more without any problems, im talking about close to 20-30wtq is what some people have gotten with the stock turbo, horsepower not so much though.

Also what is a cutout exhaust, sorry im not good with termanology for that section of the car cause ive never done an exhaust before. The only car ive had with an exhaust was the celica, but it was put on before i got it.

And like I said before, this is not something im doing right now, nor will it be anytime soon, i just want to learn as much as i can so when I get ready to actually do this I know.

[Chiquae07]

http://www.jegs.com/webapp/wcs/store...44831_-1_11529

[Gotian]

hey here is another question, what about side exhausts? is there any actual performance difference between that and a normal one?

[BLU CIVIC]

i think it's more of a "show" thing but it can be less restrictive depending on how short the run is or if it is just a straight run...like this