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2s4x0
02-04-2007, 10:05 PM
i have a non-turbo ka24de. i want to in the future turbo it but for now its not. i was wondering whast size piping for an exhaust to go with. i found the exhaust i want in two sizes 3" & 2.5" with a 2.35" inlet. What should i go with if my car wont be turbo for a while.?

kerosinek
02-04-2007, 10:15 PM
3" I have one on my 240 and I love it. It's also a NA KA. If you can, weld a resonator or something on it because 3" is a little loud.

TooHai4Yah
02-04-2007, 10:21 PM
3" but i'd highly recommend to get a resonator, n/a ka with 3" is stupid loud for some people

Phlip
02-04-2007, 10:22 PM
Three inches, stop asking questions

9524tee
02-04-2007, 11:36 PM
2.5 for now... then go 3.

Do it right.

JDMClifford
02-04-2007, 11:58 PM
i would wait till you turbo it. what other mods do u have?

!Zar!
02-05-2007, 03:10 AM
2.5 for now... then go 3.

Do it right.
Umm... No.

3" is proven to give gains everywhere over a 2.25".


Buy the 3" and you will be fine. Do it the right/proven way.

zugoi
02-05-2007, 03:51 AM
Well if cops are asses where you live then i'd just go with 2.25 but if you dont care then just go 3 inch. I had a straight 3 inch pipe with no resonator on na ka and it was crazy loud.

2s4x0
02-05-2007, 06:37 AM
sweet thanks guyz!

2s4x0
02-05-2007, 06:39 AM
now that im going with a 3" and you all say its loud. iam going to be running a test pipe with that so does that mean its probably going to be even louder im guessing??? should i even run atest pipe ??

Dream240
02-05-2007, 07:18 AM
I take it you dont have smog regulations in your area. If you do, USE A CAT!!! Shit even if you don't, USE A CAT!!

Only assholes run illegally smogged cars and ruin our planet for what....a louder exhaust and black soot on your rear bumper? Trust me your kids will thank you. Plus you get busted with no cat, kiss your car bye-bye. (smog reqd' areas) Here's a cheap solution for a decent cat.

http://cgi.ebay.com/ebaymotors/MAGNAFLOW-DIRECT-FIT-CONVERTER-240SX-D21-PICKUP-CAMRY_W0QQcmdZViewItemQQcategoryZ33629QQihZ007QQit emZ170073854632QQrdZ1QQsspagenameZWD1V

EDIT: DELETED MIS-INFO....HAVE A NICE DAY :)
Also use a silencer to help with the sound.

koukimonster139
02-05-2007, 07:54 AM
ye, non turbo your gonna want some back pressure...

but seriously when you go turbo, 3" custom made straight pipe from dp to muff. black soot on bumper is the only way to roll!

Full-Lock
02-05-2007, 07:59 AM
but seriously when you go turbo, 3" custom made straight pipe from dp to muff. black soot on bumper is the only way to roll!

lol, thats what i have, like exactly. needs a tune..

anyway, go w/ 3in. and you'll be happy. i had a 2.5 in. before and i hated it. it was like a 400 dollar waste of money since i just bought a 3in. one like 2 months later. i didn't even get close to selling the 2.5 for what i originally paid.

just go 3in right off the bat

!Zar!
02-05-2007, 10:50 AM
ye, non turbo your gonna want some back pressure...

but seriously when you go turbo, 3" custom made straight pipe from dp to muff. black soot on bumper is the only way to roll!
its been dynoed; real, nut butt. so with proof I state that 3" is better na/forced/hamster powered whatever, over a car with 2.25".

s13gold
02-05-2007, 11:07 AM
how long or how far away is your turbo kit.....?
if its a long way off...just wait for the turbo..

ripnbst
02-05-2007, 11:21 AM
Buying an exhaust thats 3" with a 2.35" inlet isnt gonna help you when you go to turbo it. When you go boosted you're gonna want 3" the whole way back. I'd say go with the 2.5" now save the extra money a 3" will cost and save it for the turbo kit later. Even if you did run the 3" now, you would have to replace it again when you went Turbo.

!Zar!
02-05-2007, 12:53 PM
Buying an exhaust thats 3" with a 2.35" inlet isnt gonna help you when you go to turbo it. When you go boosted you're gonna want 3" the whole way back. I'd say go with the 2.5" now save the extra money a 3" will cost and save it for the turbo kit later. Even if you did run the 3" now, you would have to replace it again when you went Turbo.
Umm. Please explain why a 3" on an na and 3" on a force induced would be different? Like I checked it was the exact same.

It wouldn't be beneficial for him to purchase an exhaust now, hope he can sell it later then purchase ANOTHER exhaust.

Just get the 3" now.

But on the contrair, there isn't really a huge need for exhaust. It's not like your car will explode with turbo and stock exhaust around stock boost.

So much super street misinformation around here...

HalveBlue
02-05-2007, 01:07 PM
Depending on the engine, an NA motor will sometimes power losses from increasing exhaust piping diameter; the added back pressure removes exhaust gasses from the combustion chamger more efficiently.

Of course, like I said before, this depends on the type of engine, what accessories are installed, etc.

If you're planning on doing a turbo swap down the road anyway, go ahead an just get a 3", because in the long run you'll want one anyway.

Dream240
02-05-2007, 01:10 PM
EDIT: deleted due to my retarded-ness......

!Zar!
02-05-2007, 01:25 PM
The biggest differences with back pressure is not the exhaust but the header design. Like a 4-1 or a 4-2-1.

The 4-2-1 would be best for our cars unless you have a huge turbo and only want highend.

THEN there is the downpipe. Which I haven't even see him mention. So it's still useless.

KA 3" exhaust before/after dyno (http://www.zilvia.net/f/showthread.php?t=102582&highlight=backpressure)
That thread has more information regarding the whole 2.25 vs 3 debate...

Flybert
02-05-2007, 01:32 PM
Dream240, don't respond to this thread anymore because it's obvious that you don't know what you are talking about.

3" makes more power on NA then 2.25". It's dyno proven. Alex chang did back to back dynos with both diameter exhausts on a KA. 2.4L KA's push a lot of exhaust and love 3" exhausts. Maybe you are used to driving hondas or other small displacement I4's and all your information comes from that camp but it has been proven that it doesn't apply to the KA.

white97s14
02-05-2007, 01:36 PM
3" enough said

steve shadows
02-05-2007, 01:38 PM
Umm... No.

3" is proven to give gains everywhere over a 2.25".


Buy the 3" and you will be fine. Do it the right/proven way.


He said 2.5

And its not everywhere you do lose torque in places IMO I would rather have it with a KA.

steve shadows
02-05-2007, 01:39 PM
Dream240, don't respond to this thread anymore because it's obvious that you don't know what you are talking about.

3" makes more power on NA then 2.5". It's dyno proven. Alex chang did back to back dynos with both diameter exhausts on a KA. 2.4L KA's push a lot of exhaust and love 3" exhausts. Maybe you are used to driving hondas or other small displacement I4's and all your information comes from that camp but it has been proven that it doesn't apply to the KA.

He did it on a KA24DE and that does make a difference.

The CFM rate of the dual cam is higher. Torque loss is greater with single cam engine. :hammer:

But for the guy above (original poster) If you really are seriously going turbo go 3 inch now. It will just be loud.

Anyone have the dyno graphs? from Alex? I think he posted them on Freshalloy a long time ago and I picked them apart then too iirc.

Flybert
02-05-2007, 01:45 PM
He did it on a KA24DE and that does make a difference.

The CFM rate of the dual cam is higher. Torque loss is greater with single cam engine. :hammer:

But for the guy above (original poster) If you really are seriously going turbo go 3 inch now. It will just be loud.

Anyone have the dyno graphs? from Alex? I think he posted them on Freshalloy a long time ago and I picked them apart then too iirc.

Read the original post. We are talking about dual cams here.

Here's alex chang's dyno chart of a 3" exhaust vs. stock for everyone to see. Go 3" unless you want something a little quieter. That's all that it comes down to. And if you turbo a KA, you can possibly look into an exhaust that is bigger than 3". Pretty sure Apexi GT spec exhaust would work great with turbo KA.

http://forums2.freshalloy.com/showthread.php?t=93868&highlight=5zigen+proracer+dyno

http://www.worldwidechang.com/Pics/Cars/MyCar/Dyno/NewDyno/IntakeExhaust1.jpg

markyboi
02-05-2007, 01:47 PM
get a 2.5 inch....then in a month, buy a 3 inch exhaust...and sell me the 2.5 inch for a 100 bux!

Dream240
02-05-2007, 02:16 PM
Dream240, don't respond to this thread anymore because it's obvious that you don't know what you are talking about.

3" makes more power on NA then 2.25". It's dyno proven. Alex chang did back to back dynos with both diameter exhausts on a KA. 2.4L KA's push a lot of exhaust and love 3" exhausts. Maybe you are used to driving hondas or other small displacement I4's and all your information comes from that camp but it has been proven that it doesn't apply to the KA.

You're absolutely right. I guess I dont know what I'm talking about. I did some more research and from what I had learned waaaaay back in the day was referring to exhausts LARGER than 3" being more hurtfull to NA midrange power. I will delete my previous post to avoid future confusion. So well said sir....I concede the knowledge crown to you :bowdown:

As far as exhaust noise...I am running a 3 inch cat-back with silencer and it's crazy loud above 3000 rpms. So really noise will be your only concern.

steve shadows
02-05-2007, 03:02 PM
oook But i think that dyno from Alex is comparing STOCKexaust to the upgraded racing exaust.

I am talking about comparing a 2.5 inch straight pipe with a Dynomax muffler for example to a 3 inch turbo exaust like the N1 or 5 Ziggen.

Its all water under bridge as I said, In referring to the Original Poster if he is going to go turbo, it will just be loud in the mean time as other have noted.

lilredstiffy
02-05-2007, 03:04 PM
3" at least on ka or ka-t or sr or ca

anything smaller is outdated and makes less power

aznpoopy
02-05-2007, 04:47 PM
oook But i think that dyno from Alex is comparing STOCKexaust to the upgraded racing exaust.

I am talking about comparing a 2.5 inch straight pipe with a Dynomax muffler for example to a 3 inch turbo exaust like the N1 or 5 Ziggen.

Its all water under bridge as I said, In referring to the Original Poster if he is going to go turbo, it will just be loud in the mean time as other have noted.

+1

3" may show gains over the whole range vs. stock but that doesn't mean it's ideal for n/a ka24de. there's more to exhausts than backpressure... you also want to keep the exhaust stream hot (colder = denser aka heavier aka harder to move) and the flow velocity quick (for better scavenging). too big can adversely affect both of these factors. just b/c the backpressure myth has been debunked doesn't mean it's impossible to go too big.

without more information though, its problematic to make blanket statements as to which diameter is best. there are differences besides piping diameter which can potentially affect numbers you get on a dyno...

that discussion aside, 3" with turbo plans in the future is perfectly fine.

Gilboyto
02-05-2007, 04:54 PM
I just stuck the Buddy Club Spec II on my NA KA24E (turbo eventually). Its 3" piping with a resonator right after the cat. My cat is gutted, so its ridiculously loud from what Im used to. Sounds very nice. But when you put the silencer in, it sounds like you basically have a stock exhaust (even on mine its DEAD silent).

steve shadows
02-05-2007, 05:13 PM
Thanks AZN poopy -lolzar-

thats more articulate version of what I was trying to express. :-/

randyjordan
02-05-2007, 06:26 PM
3" and DONE

messagelengf

McRussellPants
02-05-2007, 06:36 PM
I take it you dont have smog regulations in your area. If you do, USE A CAT!!! Shit even if you don't, USE A CAT!!

Only assholes run illegally smogged cars and ruin our planet for what....a louder exhaust and black soot on your rear bumper? Trust me your kids will thank you. Plus you get busted with no cat, kiss your car bye-bye. (smog reqd' areas) Here's a cheap solution for a decent cat.


good lord, first the limp wrist wanna be mod over racist jokes and now talk of purse slapping polluters.

Pollution is good because on the off chance global warming is actually caused by humans it will make more regions temperate and open to farming which will help the economy.

Dream240
02-05-2007, 07:19 PM
C'mon mc"joker"pants....

Is this the only chance you get to make yourself feel better after a long day of doing whatever it is you do?

Pollution is good because on the off chance global warming is actually caused by humans it will make more regions temperate and open to farming which will help the economy.

Huh...interesting. Consider the following:



Global Warming

Gases created through human industrial and agricultural practices (primarily carbon dioxide from burning fossil fuels and wood, as well as methane, nitrous oxide, and chlorofluorocarbons) increase the heat-reflecting potential of the atmosphere, thereby raising the planet's average temperature.

Huh...seems to me there's a little more than an outside chance it's our fault.

First of all....let's stay on point here. You say absolutely ZERO to contribute to this thread (or any other for that matter).

And second, I even admitted that I was wrong and appropriately removed the incorrect information. So if you think your useless comments, that waste bandwidth, are going to offend me...try again.

I actually contemplated taking this to PM but I felt my last comment should be viewed for all to see. I'm done with you.

Peace

McRussellPants
02-05-2007, 08:59 PM
Huh...interesting. Consider the following

consider the following

20,000 years ago the world was 90% covered in ice.

Whoever gave a caveman a catless S13 is a faggot for ruining our enviroment.

furthermore, lol answers.com, the ultimate in enviromental resources.

Gilboyto
02-05-2007, 10:06 PM
HAHAH, I love this! Keep goin!

Dream240
02-05-2007, 10:53 PM
What are you doing....? Shows over man..... go home....

http://mishilo.image.pbase.com/u47/pinemikey/large/30197711.showsoverdummy.jpg

McRussellPants
02-05-2007, 11:45 PM
lol cute PM, didn't care to read more than to see that it was pretty faggy.


Running my car catless doesn't matter since in its lifetime it will pollute less than 1/100th of what a coal powerplant does in a day.

I'll do my part to save the planet by eating alot of steak. Because Cows pollute about as much as that retard Al Gore does globe trotting in a private jet. (but ZOMG, he drives a prius oh wait, Prius batteries are as hazardous as nuclear waste)

SC_S13
02-06-2007, 12:19 AM
its probably less pollutents than the exit gases coming from dick cheney.... but otherwise...i ran a 2.5 on my sohc, pretty deep nice sound and improved power....no complains here. but im gonna upgrade to 3 when my sr comes.