HatchbackSqueegee

update 7/01 what OEM header and CAT combination can I use to bolt up to my GSR swap with WS2 (for hatch)? I'm still confused so I'll just buy whatever I need.

I've searched for a few hours and couldn't find the answer.
What does everyone do for the mid-pipe (CAT) on their exhaust?
I have a 94 SI hatch, with b18c1, stock header and WS2 (world sport 2) cat back. Currently I'm running a test pipe for the mid-pipe where the catalytic converter should be. (had local shop make it up)

I'm moving the car to California and I need to know what CAT I will need to pass the SMOG test? Is there any bolt up option I can use? With the Short headers of OEM GSR what should I use? other options?

Also how clean do the knock sensor wires have to be run not to draw attention?

roycivic92

knock on a eg. u crazy. its obd1.

HatchbackSqueegee

step 29

http://www.c-speedracing.com/howto/b18cswap/swap4.php

roycivic92

true .but only to bar it.

HatchbackSqueegee

Why would you rip it out after you bar? And still need help with my main question about CAT.

apexi_rsx

get a hi flow cat from random technology. bolts rite in

fungus mungus

Don't get a high-flow cat from anybody if you want to smog it...not legal in CA. Get an OEM replacement cat for a 94-95 GSR (2" inlet/outlet) w/CARB number. Then swap to a high flow cat later if you want better performance.

fm

fungus mungus

Oh, and make sure everything else is either stock or has a CARB sticker on it, as you're going to have to BAR the car before you smog it (unless you're somehow able to keep your old plates).

fm

HatchbackSqueegee

Ok my question for you would be. how long is the CAT/mid-pipe of the OEM GSR? There is a really big gap from the OEM GSR header to the WS2 CAT back. I have never seen the OEM GSR CAT so I have no clue how long it is or what it looks like. I've searched for hours, even in for sale AD's no one ever has a picture of this thing or how long it is. And looks like a 3' gap under the car from OEM header to WS2!

I don't care about performance I want to pass SMOG easily!

fungus mungus

I'll have to measure my OEM cat, but I can say it's definitely not 3 feet long. Probably about 10 inches or so. I don't think there's a bolt on option...you'll probably need to have a muffler shop fab the piping and put the flanges on for you. Not difficult for them to do. That's what I did with my GSR swap into my hatch. I'm using a WS2 as well, btw.

Regarding passing smog, you probably know this, but just in case you don't, you'll need to get your car BAR'd before you can smog it. You'll take it a State Referee and they check over your swap to be sure it's legal (a '94 or later motor) and everything is there (correct/unmodified ECU, wiring is good, OEM-style cat, emissions equipment all hooked up, and any aftermarket equipment has a CARB EO number). He or she will issue you a door sticker stating what motor you have in your Civic. Then you take the car to get it smogged at a regular smog place. If it passes REF, it should pass smog unless you've got issues with your emissions.

BTW, is this an obd1 motor? I hope so...it'll make your life a lot easier.

fm

HatchbackSqueegee

I just looked threw your Pictures. You have almost the exact same setup as me. Mine is a 94 civic SI white, with a/c, and 95 b18c1. So all OBD1. How clean did you rout the Knock and IAB wires? Did you even use them? I am using a virgin P72 computer then running wires from sensors threw firewall plug into computer... kind of ugly but there are no CEL's.

And looks like I have to buy a OEM GSR CAT and have it chopped up by the muffler shop?

tlarimer

iTrader: (3)

IIRC all USDM cat's are 17" or 19" in length. I am using a 12" JDM cat, so I cant be of much help other than the measurement.

jerryegk24

From gsr stock header to gsr cat there about 6 1/2 inches apart from mid pipe. Just buy two extension bolt on adaptor and you should be fine.

HatchbackSqueegee

If you could provide a link on where to buy this contraption I would love to see what it looks like?

jerryegk24

The adaptor I' talking about I don't seem them sell anywhere and only one shop I see them sell is a shop in Sacramento , ca here's There phone number (916) 429-1333.

fungus mungus

To be honest, I can't tell you how they were routed as I didn't do the swap. I can say that the Ref found absolutely nothing out of place, so the shop that did the swap did a great job.

fm

HatchbackSqueegee

Only thing I see on their website is http://www.topspeedautoparts.com/Nis...ssan-max95.htm I'll give them a call tomorrow and find out what they have for a swapped car. Just curious do you have this set up? Thanks again for giving me another option.

Your swap looks extra clean. Enjoy it, Can't wait to have mine here in CA and hope everything goes as smoothly as yours did.

hard_boiled_EG

you have to get a LS/B16 header...

because im guessing that you bought ur ws2 exhaust specify for you civic,
if you compare the LS/B16 header and GSR header the bolt patterns are the same BUT the LS/B16 header is longer, which is what you need...

up to you...i have gsr in my 92 civic, with the oem gsr header, i just made an extension for mines...

jerryegk24

HatchbackSqueegee

Yeah my WS2 was made for the civic HB, I figured that had to at least fit under the car correctly without modifying it. Looks like I'll end up doing what you did. Just keep the GSR OEM header and have the muffler place make up some type of extension for the gap between the midpipe and CAT. I really would like a bolt up solution but no one seems to have an answer out there. And I thought this was a common enough swap/problem that someone or a company would have the solution. Guess I was wrong.

HatchbackSqueegee

What OEM header and CAT combination can I use to bolt up to my GSR swap with WS2 (for hatch)? I'm still confused so I'll just buy whatever I need. Just going to start from scratch. Want OEM look/sound and bolt up to my WS2. Would ITR header and CAT fit GSR?

hard_boiled_EG

im not 100% sure if the itr header will bolt right up without any problems but i'm sure that if u can get your hands on a LS/B16 aftermarket header it'll bolt right up and make up for the gap, i say aftermarket because i've never try to install a OEM LS/B16 header on my car, im not sure if they'll clear the oil pan since they are more bulkier and might be shaped a bit different

ca-rs

Here's a photo of an OEM GSR cat, I can measure it if need be:

HatchbackSqueegee

I read on a few post last night that the GSR block is longer b/c it has a grill inside to help with rigidity. But I've still had not definitive answer on if an OEM LS or B16 will bolt up. I do like the idea of the cast iron top header as that will keep the noise down to stock levels. But I would also like to go with the largest piping and looks like Type R is the best at 2.5" in the later years or JDM. (if it will even fit the GSR) Only problem is the Type R is not cast iron upper. Guess it's a trade off I'll have to decide after I've figured out a bolt up option.

That would help out a TON. Do you have any clue what year it came from?

I spent 4 more hours last night researching to figure out what some of the differences are. Only thing I could come up with is the 94-99 GSR header is the short one (the consensus is 2" shorter). All others are same length. The chart below shows some of the differences.

HatchbackSqueegee

Does anyone know if the JDM B16B CTR header, will fit the USDM GSR? Same question for JDM B18C R fit a USDM GSR? I know the collector is 2.5" On both of them, so CAT would need to be modified to fit.