Rep Power: 288

Ok so I'm still trying to wrap my brain around this concept, because I don't know what's underneath the EX.
Quick back story,
I bought some games off some guy in my area through craigslist, and it turns out his brother had a 7th gen EX which he was selling his aftermarket header for. I was like "How much do you want?" He says 35 bucks. So I I'm like what the hell, lets see it. So he comes back with a used manifold and this down pipe looking thing, which looks pretty decent shape, especially for 35 bucks, it looked great. When he came back, he said that his brother told him that it was a Megan Racing header. I looked on the header and it has a little metal tag welded on, that says HP racing So i have no idea what it really is or if hp racing is just part of megain, but I bought it anyways.

This is what it looks like:



I got home and searched on the internet, no luck finding anything with the search term civic and hp racing, but I did find an image searching civic and megain racing which looks exactly like what I have:



Here are the problems, I think....

Pictured above, I never got those gaskets and bolts from the seller, can I use what's already in my engine bay? The stock bolts and gaskets? Or do I have to buy new ones from megan racing?

I have an LX and I'm seeing that these units are only sold for EX's, Does that mean I have to get an aftermarket or EX catalytic converter and weld it in line with the rest of the exhaust or something?

If I have to get a cat welded in, then I might as well just get a universal muffler and get a pipe bent to fit and welded in cat.

Can anyone please help? Im I missing anything?
Thanks!

 
Rep Power: 322

just get new OEM gaskets.

 
Rep Power: 512

i replace the cylinder head side gasket every time i break that seal.. the little doughnut one i reuse though.. as for the bolts, the stock ex manifold has nuts welded onto the downpipe connection flange, so you can use your stock spring bolts as long as you grab some nuts and probably lock washers to go with it.

and since you're bolting it up on an lx, you're gonna need to get a cat if you wanna be emissions legal, but i think you still need [official] documentation saying your original cat went bad/was defective so you replaced it.. also, you're gonna have to extend your O2 sensor wires to accomodate for that..

 
Rep Power: 288

Ok, sweet. I'll do that. What about the bolts that connect the header to the block? Can I re-use those?

 
Rep Power: 512

yep.. should be able to.. just remember that they have torque specs.. crank down on them and you'll strip out your block

 
Rep Power: 247

ummm yeah about that...you have studs and nuts...that sounds bad...but you can use your stockers for that too...they will work just as well

 
Rep Power: 288

Ok I gotcha, bolts and lock washers from the local hardware store. Thanks
What about the bolts that hold the header to the block?

So If i were to purchase an aftermarket EX cat back system, and an aftermarket catalytic converter designed for the EX, Can I bolt it up at home? I want to avoid taking it somewhere to be welded/done for me.

 
Rep Power: 288

Right, I'll do that for sure.

 
Rep Power: 512

here's a high flow cat/downpipe: http://www.dezod.com/pd_random.cfm

i have it on my car. it bolted right up with no CELs.. the thing is, you're gonna have to extend your O2 sensor wires

oh, and getting this would help you, too
http://www.dezod.com/pd_random_techn..._kit_civic.cfm

 
Rep Power: 288

I'm not sure what you mean? You're saying it's ok to re-use the stock nuts/bolts whatever, that hold the header to the block?

What sounds bad?

 
Rep Power: 247

yeah, just use the stock parts, they are the same as those aftermarket ones

 
Rep Power: 260

i dont think the donut gasket from ur oem manifold will fit the aftermarket one. it didnt for me. im sure u have a hp header if thats wat it says on the header. if its a megan...um same difference i guess. wont make much of a difference. i would change the cylinder head gasket between the header and the head. now...im guessing u didnt get that extra part in that picture u posted up did u? that would be ur test pipe. thats what replaces the cat in the ex versions. if u had both of those it would work..itd be kind of like converting to ex..but ur gona throw CEL's. so.. i duno. anymore questions?? for 35 bucks thats great.. i would buy the cat from dezod or the megan test pipe from dezod if i were u. extend ur 02 wires and u should be ok..

 
Rep Power: 512

the doughnut gasket fit fine on my kamikaze header paired up with a random tech downpipe..

 
Rep Power: 260

i have an obx header and my oem gasket didnt fit. and still havnt gone to NAPA to pick up another one so i have a disgusting leak.

 
Rep Power: 252

my oem donut gasket did fit with my megan header and test pipe. i did however buy a new one from Honda.... its was only a couple bucks.

 
Rep Power: 512

honda OEM doughnut gaskets are 10 bucks from hondaautomotiveparts.com.. 14-16 at a dealership...

 
Rep Power: 288

Edit, pictures added:

 
Rep Power: 288

Awesome, this is great information for me. Thanks for your help.

If I were to buy that high flow cat/down pipe, and then buy an aftermarket 'cat-back' exhaust system for the EX, can I just bolt it up at home on my own?
I'm trying to avoid taking it for welding and such.

 
Rep Power: 512

Yep.. That random tech downpipe/cat is a direct fit to an ex system. That's what I meant by "it bolted right up." I would recommend getting that gasket kit, too. You get a new doughnut gasket, downpipe-midpipe gasket, and new hardware for both the header-downpipe and downpipe-midpipe connections.

 
Rep Power: 260

if u do buy that high flow cat/down pipe...then u should give me that extra part u got for free. if u get the part from dezod then u wont need the test pipe that u have lying there also

 
Rep Power: 288

Right I see what you mean, Or i could sell i to you...Ha ha, or I guess I could just use it instead of the cat/downpipe combo. Or I could buy just a new aftermarket cat and use the piping from the test pipe. nice.

 
Rep Power: 0

Multiple things you could do, but living in Cali means you're surrounded by enviro-*****. Be sure and carry extra ammo if you run without a cat.

Language Trivia of the day: Exhaust in German is "Auspuff".

 
Rep Power: 288

^Ha ha, seriously. Thanks for the input. I think I'll just wait until I get the cat/downpipe combo, AND a new EX cat.

I read an article once where Turbo Magazine actually dyno'd a car with a test pipe and with a high flow cat, and concluded that the test pipe added a maximum of one horsepower over the high flow. In my opinion, it's not worth the one horse. I don't have a cite-able source other then my brain. I'd rather just give the bacon a loud ****-YU-BEEACH! As a stroll by knowing my car is legal.


"***-puff" ?

 
Rep Power: 256

wow man u got an amazing deal. See good things happen to you when you do good to others LOL. Thanks for the washers got my flex all bolted up and all i need is an alignment and i'll be good to go. Good luck with the exhaust. Its gonna add some power to ur ride.

 
Rep Power: 288

Ha ha! Thanks dude. I know what you mean. Good Karma right? Heh I think it's more just good chance, but either way I'm so excited that I got it, because now I can finally get that new exhaust I'm looking for and a little nicer under the hood. That's awesome that you got the flexes bolted in. Alignments are essential of course, do you have a thread with new pictures of your drop? I'd like to see it too!

 
Rep Power: 256

they arent very low yet so i havent posted yet. Rite now its like 1.5"ish drop. i want it to be a bit lower so i still need to drop it a bit more and get an alignment then i should be good to go. I'll definantly post pics. Honestly I dont think the flex were the best choice for me. The car is a daily drier and the susension is really really tight and kinda bumpy but i think they just need to be setup a bit better.

 
Rep Power: 329

I have a HP Ceramic coated racing header and high flow down pipe. If anyone wants it I will let it go cheap. If you click my ride in my sig you can see pics.

The factory doughnut does not fit, I will also recommend changing the exhaust gasket against the engine.