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-   -   Installed Exhaust now my car feels slow (#/f/showthread.php?t=193606)

flclsteve 05-20-2008 08:14 PM

Installed Exhaust now my car feels slow
 
Just installed my exhaust and it feels very slow not saying my car was fast before but it just seems to take alot long to climb the rev's when driving any ideas why? its a catback with 3 inch piping on a na ka i know 3 inch is big just didnt think it would affect any thing.
ka24e
cold air intake
cat-back 3 inch pipe
http://img122.imageshack.us/img122/5...oaaaaa2xw2.jpg

wickedS14 05-21-2008 12:22 AM

:tweak: And your wondering why it takes long to get up to rev. 3inch on a 24e, thats overkill. You sir need all the back pressure you can get. It's like blowing through a mcdonalds straw to then blowing through a papertowel roll. Put back on your other exhaust and save the 3 inch for a higher hp motor. Just my 2cents!

apex 05-21-2008 12:26 AM

do a tune up

flclsteve 05-21-2008 12:28 AM

Quote:

Originally Posted by wickedS14 (Post 2053736)
:tweak: And your wondering why it takes long to get up to rev. 3inch on a 24e, thats overkill. You sir need all the back pressure you can get. It's like blowing through a mcdonalds straw to then blowing through a papertowel roll. Put back on your other exhaust and save the 3 inch for a higher hp motor. Just my 2cents!

still learning makes sense like a dual cam or sr?

ALEXTHESUS*PECT 05-21-2008 12:33 AM

for ka's i would say 2.5" is max for na. sr or turbo ka would be 3". you got no torque, and we all know with that sohc, you got no real top end either. but i'm sure you got a loud fucken car!

dino6192 05-21-2008 12:34 AM

Quote:

Originally Posted by apex (Post 2053743)
do a tune up

for what? he needs backpressure! 2.5 is the largest I would have gone on your car. nice exhaust though.

flclsteve 05-21-2008 12:35 AM

Quote:

Originally Posted by ALEXTHESUS*PECT (Post 2053766)
for ka's i would say 2.5" is max for na. sr or turbo ka would be 3". you got no torque, and we all know with that sohc, you got no real top end either. but i'm sure you got a loud fucken car!

seriously it sounds fucking crazy i need to post the video

MTalon 05-21-2008 12:42 AM

if he still has the stock dp, hes got back pressure. If he installed headers, and a test pipe and the exhaust then I would say theres not enough back pressure

jinesz32 05-21-2008 12:43 AM

i had a 3" BC exhaust on my na ka24de, feels like it ran better.

then again yours is 24e, not really sure about those. i just heard the ka24de's like to breathe.

wickedS14 05-21-2008 12:49 AM

What were you running before that? stock? I got a custom 2.5 straight piping w/ a glass pack resonator angled out to apexi n1 tip for my bone stock kade. I chirp through 2nd whenever and spin through 3rd if raining "bald tires".:coolugh:

flclsteve 05-21-2008 12:51 AM

[ame]http://www.youtube.com/watch?v=amAA-rJhH8A[/ame]
so heres the vid just in case ur wondering so i guess i should just go do a swap now =P or get smaller pipeing

MTalon 05-21-2008 12:54 AM

couldn't even wait to get the car off the jack before starting it.. sheesh.

Felipe 05-21-2008 12:56 AM

hahaha... nice...


just put a silensarrrrrrrr

apex 05-21-2008 01:02 AM

Quote:

Originally Posted by dino6192 (Post 2053768)
for what? he needs backpressure! 2.5 is the largest I would have gone on your car. nice exhaust though.

shut the f up i got a sohc with headers 3'test pipe and 3' catback
here me gettin sideways
http://img187.imageshack.us/img187/5...f11806fxg6.jpg
http://img187.imageshack.us/img187/5...089a8ad896.jpg
http://img187.imageshack.us/img187/8...9a31984hy3.jpg
http://img187.imageshack.us/img187/8...efff59fa80.jpg

sunnys14 05-21-2008 01:58 AM

For KA's, 3" ftmfw.

Big engines like to breathe, the end.

Jeezy240 05-21-2008 09:17 AM

i feel that 3 inch is too big. your loosing power. theres not enough backpressure. if you were to put a cat in there and a silencer then i think it might help some.

flclsteve 05-21-2008 10:14 AM

there is a cat its a cat back system I'm sure I can ghetto fab some silencers or somthing

airforceone451 05-21-2008 10:32 AM

Obviously with a bigger diameter aftermarket exhaust system you will lose power in the lower powerband, but you also free up space so you gain power in the upper rpms...I don't think 3 inches is overkill for an n/a ka

5t341tH 05-21-2008 12:39 PM

try putting a highflow cat in. i was recommended to do so by a muffler shop.

bigjacsoc 05-22-2008 10:46 PM

if u have a test pipe downgrade to a cat or a resonated test pipe to get ur backpressure back. u can get resonated from www.projectnissan.com

S14DB 05-22-2008 11:06 PM

Quote:

Originally Posted by wickedS14 (Post 2053736)
:tweak: And your wondering why it takes long to get up to rev. 3inch on a 24e, thats overkill. You sir need all the back pressure you can get. It's like blowing through a mcdonalds straw to then blowing through a papertowel roll. Put back on your other exhaust and save the 3 inch for a higher hp motor. Just my 2cents!

Quote:

Originally Posted by ALEXTHESUS*PECT (Post 2053766)
for ka's i would say 2.5" is max for na. sr or turbo ka would be 3". you got no torque, and we all know with that sohc, you got no real top end either. but i'm sure you got a loud fucken car!

Quote:

Originally Posted by dino6192 (Post 2053768)
for what? he needs backpressure! 2.5 is the largest I would have gone on your car. nice exhaust though.

Quote:

Originally Posted by MTalon (Post 2053790)
if he still has the stock dp, hes got back pressure. If he installed headers, and a test pipe and the exhaust then I would say theres not enough back pressure

WTF are you people talking about back pressure like it's a good thing?

Check for exhaust leaks.

Are we talking ass dyno here? Cause sure it will feel different. Doesn't mean you're loosing power.

flclsteve 05-23-2008 10:33 AM

Quote:

Originally Posted by S14DB (Post 2058542)
WTF are you people talking about back pressure like it's a good thing?

Check for exhaust leaks.

Are we talking ass dyno here? Cause sure it will feel different. Doesn't mean you're loosing power.

No we are not talking dyno but ya driving with it its pretty noticable doesnt seem to be any exhaust leaks but i can live i guess

apex 05-23-2008 04:28 PM

u need a tune up of sumthing
there r even dyno sheets posted on here if u search that shows
3" only has gains no loses might feel like it but u gained more topend with 3"

Mikey213 05-23-2008 08:23 PM

im not sure, but i think those dynos are only for the DOHC...

cornercarver240 05-23-2008 11:33 PM

why does everyone keep saying he needs backpressure. no he doesn't, backpressure is bad for performance. the reason it feels slower is because the exhaust is too big, it flows a very large amount of air but the velocity has been reduced a great amount, which reduces scavenging thus lowering torque. it can no longer expel the air out efficiently, and on a car that already doesn't have great volumetric effieciency this will be much more obvious. bigger is not always better, you need to find what's best for your application.

BoostedCoupe 05-23-2008 11:43 PM

wow backpressure this backpressure that. I have 3" headers 3" cat and catback and it fills alot better than stock or anything else. ka's love to breath dont believe me? look at this then
#/f/showthread.php?t=177055&highlight=ka%27s+love

DohcKA 06-04-2008 04:09 AM

sell your exhaust.... dump it into something more worth your money at the time.... stop fart canning down the street

projectRDM 06-09-2008 07:02 PM

What a whole thread of fail.

Backpressure is something some fool made up 60 years ago and people still swear by it. An engine does NOT need backpressure, period. You want to get all the exhaust air out as quick as possible to avoid creating backpressure, which chokes down the engine. A very small amount of lowend torque is lost due to the added flow, but it's hardly noticeable even on paper. There has been TONS of dyno graphs shown for nearly 20 years proving that the bigger the exhaust you have on a KA, the more power you make. Done.

GeneStarWindGSW 06-11-2008 02:47 PM

Quote:

Originally Posted by projectRDM (Post 2098622)
What a whole thread of fail.

Backpressure is something some fool made up 60 years ago and people still swear by it. An engine does NOT need backpressure, period. You want to get all the exhaust air out as quick as possible to avoid creating backpressure, which chokes down the engine. A very small amount of lowend torque is lost due to the added flow, but it's hardly noticeable even on paper. There has been TONS of dyno graphs shown for nearly 20 years proving that the bigger the exhaust you have on a KA, the more power you make. Done.

Yea i have a custom 6" exhaust.

I just keep on gaining that power http://www.tamparacing.com/forums/ta...iles/laugh.gifhttp://www.tamparacing.com/forums/ta...iles/laugh.gif

GeneStarWindGSW 06-11-2008 06:59 PM

Wow guy can't make a joke w/o getting a neg rep? wack ass Z people

well i have a 3" BC Spec II on my N/A KA


http://tinyurl.com/4qg4s6

http://tinyurl.com/52lvz7


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