Headers, (DC) - Honda Prelude Forum

Joon525 · 06-30-2001, 03:05 PM

I was going to post this in the 5th gen forum but it's kinda universal. Today I was spraying WD40 on all the bolts I could get to to prepare for the full install tomorrow. I decided to see if I could break torque on them as well. The cat bolts I got loose (amazingly enough)..BUT....On the downpipe of the stock header inbetween the flange where the downpipe/primaries connect and the cat there's this metal piece that extends upward. In this piece there are 2 bolts. Here are mine

See the one that's loosened? The WHOLE thing turns when I loosen it. Bolt AND nut....but as you can see it's all coming out. Has anyone else experienced this? I tightened it back down for now.
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F*ck I just thought of something.....that upward flange/brace wraps around the stock downpipe/collector and bolts itself to it. I could un-do those bolts and just bend back the flange on the aftermarket header and then attach that same brace.
Crap....what would you do? I think I might just un-do that brace, any suggestions?

(I kinda answered my own question there so how's this.......Has anyone used that stock brace?) Some of the brace is pictured below

SteveV · 06-30-2001, 03:30 PM

i'm not sure if that stock brace/bracket will work with your new header. for my Mugen, it came with a new brace, but that ended up cracking and breaking on me. So rather than having my header hang there unsupported, I rigged up my own new brace with an angle-shaped piece of metal.

Try unscrewing the bolt on that c-clamp thing that holds the brace to the header. Then install your dc header and see if it lines up with the stock brace.

Joon525 · 06-30-2001, 03:46 PM

Quote:

Originally posted by SteveV
for my Mugen, it came with a new brace, but that ended up cracking and breaking on me. So rather than having my header hang there unsupported, I rigged up my own new brace with an angle-shaped piece of metal.

Damn how come almost EVERYONE I know that has an aftermarket header breaks there. ImagePree and DY101's broke there too.

Quote:

Originally posted by SteveV
Try unscrewing the bolt on that c-clamp thing that holds the brace to the header. Then install your dc header and see if it lines up with the stock brace.

That is exactly what I'm going to try tomorrow. If it lines up alright I'm going to break/bend off the one that's already on the DC header.

SteveV · 06-30-2001, 05:43 PM

hmm, I didn't realize that other people had theirs break too. I guess that thing is subject to alot of torque and twisting from the motor.

So, the brace for the DC is already welded on to it?

71dsp · 06-30-2001, 05:55 PM

That bolt is a stud, i.e. it's threaded like a bolt on both ends. If the whole thing turns, it's no big deal, just remove the stud and nut, and reinstall both when you install the aftermarket header. You probably won't be able to use that hanger, as I haven't seen an aftermarket header that fit exactly like stock (including the Mugen).

Joon525 · 06-30-2001, 06:08 PM

Quote:

Originally posted by 71dsp
That bolt is a stud, i.e. it's threaded like a bolt on both ends. If the whole thing turns, it's no big deal, just remove the stud and nut, and reinstall both when you install the aftermarket header. You probably won't be able to use that hanger, as I haven't seen an aftermarket header that fit exactly like stock (including the Mugen).

Ah........Thank you!

Joon525 · 06-30-2001, 06:10 PM

Quote:

Originally posted by SteveV
So, the brace for the DC is already welded on to it?

Pretty much.

Spocko · 06-30-2001, 06:36 PM

You don't really need to use that flange to hold it up or in place, the header is DEAD SET the way it is without it. I can see that the OEM one would probably need it more considering that it weighs like twice as much, but not with the DC. I was actually thinking about cutting it off to save a few pounds. Maybe I'm just crazy???

GSR-Killa · 07-01-2001, 03:13 AM

I torched my hanger and was able to move it after that before it cooled down.. so then I hooked the flange onto the top.... The header was probably the biggest pain in the world. I thought my back was going to break when doing it. That's the lsat time I will ever do my own headers. I think I'm just going to have some shop do it for me the next time. Damn thing took forever to put on to because it just didn't fit too well. Oh yeah, you can just cut off that stupid hanger so it gets out of the way.

ImagePree · 07-01-2001, 04:12 AM

installing headers just might be the best $40 spent...

or maybe i'm just lazy! :finger: :finger:

good luck ray.

Joon525 · 07-01-2001, 08:50 AM

Quote:

Originally posted by imagepree
good luck ray.

Thank you. I'm in the middle of doing it now....that nut came off with the stud staying in place this time...strange but good.

po0p · 07-01-2001, 01:03 PM

my dc headers didn't fit and so i just left it hanging without bolting or fabricating it to fit. I thought it would be ok as long as i don't hit the ground at that point... didn't seem likely so i just left it. I hope it'll be fine. ANyone else didn't use the stock bracket support thing?

hey joon: take pics of what you ended up doing!

iranman · 07-01-2001, 02:45 PM

Quote:

Originally posted by po0p
ANyone else didn't use the stock bracket support thing?

*Raises Hand*

I just cut off the piece of metal that was supposed to line up with the stock support bracket bolts and used a combination of the stock bracket and a c-clamp to hold it in place.

Personally, I think Spocko's correct: the downpipe is held into place by the exhaust manifold (which happens to be securely attached to the engine block) and the catalytic converter/exhaust pipes (which are held into place by hangers).

Joon525 · 07-01-2001, 02:56 PM

OK I actually used that flange.......but I'll tell you more about this crazy adventure when I'm done putting the pedals in THATPRELUDEGUY's car....in a word the install was kinda sucky. OK 2 words. More later.

Spocko · 07-01-2001, 03:54 PM

Yeah, the DP is DEFINATELY secure by all means- you could strike that thing with a sledgehammer and it wouldn't budge an inch even without the hanger connected- don't believe me- see how easy it is to remove it. PITA is what it is- the torque on the cat bolts are soo tight, I had to use a 3 foot breaker bar on top of the ratchet, and then KICK the damn thing to break the bolts loose. AND the header itself is so tightly fitting to the engine too, that its overkill to "hang" it to something to hold it in place. I would be willing ot bet that you could hook up the header, then the DP and secure those bolts, and then slide the DP onto the cat and leave it at that- meaning not putting on the cat nuts, and I DOUBT it would move(although there MIGHT, might be a SLIGHT leaking of exhaust there a the cat, but I wouldn't be surprised if there wasn't either.

Wiggle room is a joke when it comes to installing a header- make it easy on yourself and forget about hooking up that hanger section- in fact, cut it off or bend it out of the way to make the install easier. That's what I would do if I had to reinstall it again.

Joon525 · 07-01-2001, 04:06 PM

I'm done with the install........LONG story......I'll post pictures of the stock header next to the DC Sports one too.....but I am DIRTY and need to shower and then eat....

Joon525 · 07-01-2001, 04:10 PM

Hey does the CC header smell when you first put it in? After running it for a bit it smells.....not terrible and not a LOT but there's definitely an odor.

SADWAP97 · 07-01-2001, 04:15 PM

did you use a new gasket? if not, that may be a cause for the odor.
just a possibility.

Joon525 · 07-01-2001, 09:48 PM

Well I got it in. I also got it in using that vertical flange in the middle of the collector/downpipe. Let me tell you it was a B*TCH to get on there. Also that nut that I had a problem with earlier.....it came out today no problem....the stud stayed in this time.
Anyway me and THATPRELUDEGUY only broke one bolt which was one of the ones that holds the header to this mounting frame in the car. No big deal. Upon screwing the downpipe and the primaries together I stripped one of the holes in the flange on the primaries. This is where it gets interesting....drove to a parts store and got a bolt that is smaller in diameter that the one supplied by DC....it's also longer....we went to get a nut to put on the other end of it at another store as the parts store I went to was out of nuts. Got the nut, get in the car and BOOM!!! Rain and HAIL comes showering down like crazy....not only that but the mall we were at to get the nut was PACKED beyond belief! Get home to my disabled car and got to work. I had to use the jack to push up the downpipe a bit to get the 2 flanges to meet perfectly.....this is why I stripped the hole in the first place.....2 out of the three holes lined up fine but the third one was jacked...basically a kinda poor fitment problem (maybe only on the one I got)..... So 2 out of the 3 holes in that flange are held by the bolts that came with the header. The third hole is filled by a bolt and a nut on the other side of the flanges with washers on both sides...I think it should be OK.
There's a burning smell coming from the engine area now though...I think it's the nut I bought....it had nylon in it to help it lock down, I felt it later and it's hardened in a dripping formation...I guess I'm smelling burning nylon. Or has anyone else with a CC header smelled something similar when they first put theirs on?
ANYWAY.....the pics:
Stock VS. DC downpipe

Stock VS. DC downpipe 2

Stock VS. DC downpipe 3

Stock VS. DC Primary

Notice that the opening's in the stock header are actually bigger than the DC Sports header? I couldn't figure this out for the life of me. But then I looked into the openings and this is what I saw
Stock merge

DC Merge

It might be kind of hard to make in those 2 pictures but the merges are actually smoother on the DC. Other notable differences are that the primaries on the DC are longer than those on the stock header. I don't know which is better to be honest though. Ask someone else more knowledgable.

One last note......THATPRELUDEGUY has the Neuspeed N2 header.....I brought my DC primaries over to his car before we bolted it up....the similarities are unbelievable. We really can't tell what the differences are. The welds look a little different but the pipe diameter and curves are like 99.9999% the same to us.

Done *whew!*

Joon525 · 07-01-2001, 09:49 PM

Quote:

Originally posted by SADWAP97
did you use a new gasket? if not, that may be a cause for the odor.
just a possibility.

All the gaskets were new....in the above post you can see where I think the smell is coming from.

ImagePree · 07-01-2001, 10:02 PM

ewwwwwwww
who's hairy leg? :finger: :finger: MARK!

SADWAP97 · 07-01-2001, 10:45 PM

great pictures joon! hmm.. i was also wondering about the smaller openings on the DC header. interesting. i think i'll just stick with my stock header.

Joon525 · 07-01-2001, 11:04 PM

Quote:

Originally posted by SADWAP97
great pictures joon! hmm.. i was also wondering about the smaller openings on the DC header. interesting. i think i'll just stick with my stock header.

If you saw the merges in person you might not think so.

o0OO0o · 07-01-2001, 11:23 PM

interesting pics! let's make sure we have this thread FAQ'ed later on.

Joon525 · 07-01-2001, 11:37 PM

Oh yeah.....we measured the holes.....the DC is about 4cm across...the stock is about 4.4~4.5cm across. The stock one looks bigger in these pics because the camera is a bit closer.

po0p · 07-02-2001, 01:49 AM

yeah i was confused when i compared the stock to the dc as well. My shop teacher gave me a "you fool" look.

I didn't notice the stock "merges" were so rough though.

Smoother flow....but it's smaller....

Joon525 · 07-02-2001, 08:54 AM

The stock header is HEAVY compared to the DC....just thought I'd throw that in there.

OvaDaLimiT · 07-02-2001, 02:02 PM

I don't think there's much more to add. FAQ'd!