PDA

View Full Version : K20A2 Exhaust



Cals si03
05-08-2008, 06:50 AM
I currently have a K20A2 in my car with the stock EP3 exhaust from headers to end of cat, Skunk 2 cat-back exhaust. The pipe that connects the headers to the catalytic converter was rigged so it would fit the current position of the EP3 exhaust. Piece of pipe was welded. What can I buy to get rid of this and make the exhaust "solid" instead of having it rigged? Please help I want the swap to be proper.

clujalolo
05-08-2008, 05:33 PM
I currently have a K20A2 in my car with the stock EP3 exhaust from headers to end of cat, Skunk 2 cat-back exhaust. The pipe that connects the headers to the catalytic converter was rigged so it would fit the current position of the EP3 exhaust. Piece of pipe was welded. What can I buy to get rid of this and make the exhaust "solid" instead of having it rigged? Please help I want the swap to be proper.

umm from what i know, you have to rig the exhaust to make it fit properly. You ahve to cut the exhaust 3in to make it fit to a type-s RH. UNLES you get a type-s header and cat, with a type-s midpipe. Im not 100% but i think this is the only way to make it fit without actually cutting it, but im probably wrong lol

SyckSiR
05-08-2008, 05:39 PM
I currently have a K20A2 in my car with the stock EP3 exhaust from headers to end of cat, Skunk 2 cat-back exhaust. The pipe that connects the headers to the catalytic converter was rigged so it would fit the current position of the EP3 exhaust. Piece of pipe was welded. What can I buy to get rid of this and make the exhaust "solid" instead of having it rigged? Please help I want the swap to be proper.

ok, first off, its a header, there is only one, no need for the plural.

you need an ep header and cat or ep specific race header. you currently have an rsx-s header and cat.

Cals si03
05-09-2008, 05:27 AM
I currently have an EP3 cat and a RSX S header. So, A EP# race header would do the job? No midpipe or anythign else involved?

eclecticteg21
05-09-2008, 11:01 AM
midpipe comes after the race header.

you can used stock a3 header, cat, midpipe, etc and it will be fine.

or get a race header and call it day.

dont make it more difficult than it is lol.

Cals si03
05-09-2008, 12:45 PM
Well that mean I would have to buy a Race Header and a midpipe, then hook up to my cat back exhaust? Correct? Sry, I just want this to be a good setup. Any O2 sensors involved?

RedSiBaron
05-09-2008, 02:03 PM
wow way to read sycksir, stop bein a dick to everyone and maybe concentrate on helping people...


alright heres the deal with the type s/type r (itr or ctr) spec header/downpipe/midpipe versus the usdm ep3 header/downpipe/midpipe

the first issue is that the header and downpipe from the type s/itr/ctr is that they are longer than our usdm ep3 header, so the us midpipe is too long

also the flange on the type s/itr/ctr header is angled, so the flange on our midpipe wont be the right angle, even if it were the right length...

the midpipes on the type s/itr/ctr are shorter and have the angled flange



so your options come down to a type s/itr/ctr header to match a type s/itr/ctr specific midpipe

OR

a usdm ep3 spec header to match a usdm ep3 spec midpipe

OR

that little adapter pipe between a type s/itr/ctr spec midpipe and a usdm ep3 header


i hope that helps you decide what you want to do, but if i were ANYONE, i wouldnt screw around with usdm ep3 spec stuff, id just use type s/itr/ctr spec header+ type s/itr/ctr spec midpipes

you will consistently get larger diameter piping and you dont have to play the "will it fit game"

the type/itr/ctr spec headers all bolt up to the k20, though you may need the CTR front sway bar to clear the header, depending on specific headers, though it may be all, i have the ctr sway so im not worried...

ill note that you are killing your power with that usdm ep3 header, its VERY restrictive, especially in the cat

look up hte ITR header thread on here, it will show you what i mean about the restriction...

alright, hope this helped

it sounds like you have a type s spec cat back exhaust...especially with that adapter

Cals si03
05-11-2008, 06:49 AM
Thanks for the post it is greatly appreciated. I have a type s header on my
K20A2. There is a custom piece to hook the header with the cat. I want to get rid of the custom piece. In order to do this all I would need is a Type s midpipe? So, it would go Type S header, Type S midpipe, then EP3 skunk 2 cat-back? Please let me know. Thanks.

BarracksSi
05-11-2008, 07:20 AM
Thanks for the post it is greatly appreciated. I have a type s header on my
K20A2. There is a custom piece to hook the header with the cat. I want to get rid of the custom piece. In order to do this all I would need is a Type s midpipe? So, it would go Type S header, Type S midpipe, then EP3 skunk 2 cat-back? Please let me know. Thanks.

I think that'll work, yes. Another option would be a Type S header & cat, then a JDM/EDM CTR catback, but that'll be more costly, of course. I've got a Type S header & cat with a JDM Fujitsubo catback.

The secondary O2 sensor wire will be just barely long enough to reach, but I'd recommend getting an extension of about 3" just to be safe. Casper's Electronics should be able to make one if you call 'em up and ask.

dcmpbl
05-11-2008, 02:35 PM
"Personal Experience Disclaimer"---- Type-S spec Comptech shorty to Type-s cat to cut & re-welded Magnaflow catback midpipe (EP spec) to the Magnaflow's axle back piece. The only thing I would (and want) to do is change out the midpipe for a type-s spec or I have another Magnaflow midpipe to cut/reweld by a pro for better fitment. My current one rattles when it is wet....

Cals si03
05-12-2008, 07:17 AM
Should I get a Type S cat or will the header and midpipe replace that? As far as O2 snesors what will I need so my check engine light won't come on.

RedSiBaron
05-12-2008, 08:25 AM
Should I get a Type S cat or will the header and midpipe replace that? As far as O2 snesors what will I need so my check engine light won't come on.

ok lets clear something up here, header refers to the primary pipes, the downpipe is the big pipe off the header attached as part of the cat, and the midpipe is the piece between cat and the axle back...

Cals si03
05-12-2008, 09:01 AM
Ok, so the welded piece is the down pipe. The connection that is crappy is the downpipe and the cat. Should I just replace the header with a race header? Then where do the O2 sensors go? Thansk for all the help guys....

RedSiBaron
05-12-2008, 09:24 AM
Ok, so the welded piece is the down pipe. The connection that is crappy is the downpipe and the cat. Should I just replace the header with a race header? Then where do the O2 sensors go? Thansk for all the help guys....

uhh...i dont think you are understanding...the connection issue is between the cat and the midpipe, the downpipe and cat are the same piece...

there are places on the raceheader for 02 sensors but you will throw a code and unless you have kpro you are wasting your time with a RH...youd be better off with a type s or type r header and downpipe...and even with the race header you still have the same issue, you need it to be type s or type r specific...

also what you need to understand is you cant just buy the downpipe/cat from a type s, you need to buy both the header and hte downpipe/cat

making sense???

Cals si03
05-13-2008, 06:09 AM
Ok, starting to make sense. Is there a diagram of the EP3 exhaust anywhere on this site??? That would be key. Basically, my check engine light is on for the primary O2 sensor. I want ot fix this and at the same tiem replace the filler piece. I have a Type S header and I need a what to hook up to the Cat?

Princess
05-13-2008, 06:26 AM
Are you 100% sure you have a k20a2? That's the RSX-S engine until '05.

talonXracer
05-13-2008, 06:48 AM
If your exhaust is not making any contact with the chassis and is not leaking then why mess with it?

The EP3 header/cat assembly is shorter than the typeS header and cat by about 3". This three inch difference is made up on the cat end of the midpipe.

Here is a pic showing a EP3 length midpipe, the red line signifies where the typeS mid-pipe/cat flange would be located at.
http://i54.photobucket.com/albums/g96/talonxracer/eld246JPG1.jpg


the typeS would have its flange just prior to the bend on the midpipe that is closest to the camera.
http://i54.photobucket.com/albums/g96/talonxracer/ssrandcat-1.jpg

Draw7Seven
05-13-2008, 06:58 AM
Ok, starting to make sense. Is there a diagram of the EP3 exhaust anywhere on this site??? That would be key. Basically, my check engine light is on for the primary O2 sensor. I want ot fix this and at the same tiem replace the filler piece. I have a Type S header and I need a what to hook up to the Cat?

You don't even need a diagram, dude. From the engine to the ass of your car:
-Header comes off the engine (stock headers are commonly called exhaust manifolds)
-Downpipe/Catalytic Converter comes off the header
-Midpipe comes off the downpipe/cat
-Axleback comes off the midpipe

One thing to realize about buying a part to solve your problem: if you're going to be continuing to mod the car for performance, look into a race header. RACE HEADERS REPLACE TWO PIECES AT ONCE: THE STOCK HEADER AND THE DOWNPIPE/CAT. They flow better because of the easier angling they make as they snake towards the midpipe and the elimination of the constrictive catalytic converter. To get rid of your CEL, you'll have to get an o2 sim (look it up). It sounds to me like a race header would solve your problems pretty well, but it will also make you illegal for emissions.

talonXracer
05-13-2008, 07:09 AM
RACE HEADERS REPLACE TWO PIECES AT ONCE: THE STOCK HEADER AND THE DOWNPIPE/CAT. They flow better because of the easier angling they make as they snake towards the midpipe and the elimination of the constrictive catalytic converter. To get rid of your CEL, you'll have to get an o2 sim (look it up). It sounds to me like a race header would solve your problems pretty well, but it will also make you illegal for emissions.

There is no reason to have to run a race header with no cat. I have run a cat on both race headers I have owned for the EP3, a JRrh and a SSR tri-Y. Both accepted a universal cat with ease.

Sure I lost about 3-4 whp on top, but gained ALOT in the midrange and down low, probably 12-13 ft lbs of torque. That makes a huge difference on te street. If your car is a DD, it just doest make sense to loose power where it is used all the time.

RedSiBaron
05-13-2008, 07:10 AM
Are you 100% sure you have a k20a2? That's the RSX-S engine until '05.

uhhh, he said he has stock usdm ep3 header on his k20a2, thats why it doesnt bolt up without an adapter...


There is no reason to have to run a race header with no cat. I have run a cat on both race headers I have owned for the EP3, a JRrh and a SSR tri-Y. Both accepted a universal cat with ease.

Sure I lost about 3-4 whp on top, but gained ALOT in the midrange and down low, probably 12-13 ft lbs of torque. That makes a huge difference on te street. If your car is a DD, it just doest make sense to loose power where it is used all the time.

werd to this mans knowledge...thats the route im going!!!:mbiggrin:

(thx again by the way talon :mwink:)

talonXracer
05-13-2008, 07:14 AM
uhhh, he said he has stock usdm ep3 header on his k20a2, thats why it doesnt bolt up without an adapter...


The stock EP3 exhaust will fit a K20A2 with absolutely no issues whatsoever!

Reread his posts, he has a typeS header and downpipe with a EP3 cat and specific catback. He had to have a downpipe adaptor made. The EP3 cat has a much smaller opening than the typeS head pipe and will create some flow issues.

And no problems, I try to help all if I can.

RedSiBaron
05-13-2008, 07:22 AM
The stock EP3 exhaust will fit a K20A2 with absolutely no issues whatsoever!

Reread his posts, he has a typeS header and downpipe with a EP3 cat and specific catback. He had to have a downpipe adaptor made. The EP3 cat has a much smaller opening than the typeS head pipe and will create some flow issues.

And no problems, I try to help all if I can.

ahh, his post is confusing based on the first one, hadnt looked in a while and forgot his second post saying that, but all the same heh...yah it all bolts up...

Cals si03
05-13-2008, 09:04 AM
What TalonXracer said is correct. So I need to buy what?

talonXracer
05-13-2008, 09:15 AM
I would retain the custom setup as long as it isnt leaking. A custom piece is the same as rigged. Keep what you have untill you decide to go with a RH, then you will again have to "rig" "custom" weld your exhaust in order t have a cat.

Cals si03
05-14-2008, 06:54 AM
It is leaking a little bit. If I get a race header it will hook directly up to my cat back exhaust?

RedSiBaron
05-14-2008, 07:04 AM
It is leaking a little bit. If I get a race header it will hook directly up to my cat back exhaust?

yup it will...AS LONG AS YOU GET the same application header as the catback

if its a type s/itr/ctr catback get a type s/itr/ctr race header

if its a usdm ep3 catback get a usdm ep3 race header

:mwink: and dats the troof

Cals si03
05-14-2008, 07:33 AM
Sounds good. What about O2 sensors?

RedSiBaron
05-14-2008, 07:51 AM
Sounds good. What about O2 sensors?

i believe you will need 1 extension, and the other will be a tight fit, if you run a race header and have a stock ecu you WILL throw a code...you can trick it with a 02 sim, OR you can get kpro...as talon and i have discussed, a raceheader without kpro is not going to get you the gains it could, and the whole 02sim thing and not running a cat confuses the shit out of the stock ecu (or atleast this what i thought you were saying doug, correct that last bit if its wrong, :mwink:)


OH ALSOi have been screwing around trying to decide if i should get a second extension before my install just to be safe with my ITR header...anyone have any thoughts on this???