Its taken me a long time to get the Topspeed Header on my car, and working properly, but the header project is finally complete and I thought I'd share my thoughts with you guys.

I bought the header used from another Acurazine member. Upon arrival and inspection I found the header to be of pretty good quality. It is made of stainless steel, felt pretty substantial yet weighed much less than the OEM header. All the welds looked good, all the tubing lined up with the holes, there weren't any lips that needed sanding/grinding. Since it was used it didn't have the mirror shine that a new one would but the previous owner did a good job of cleaning it up.

Installation: I tried to do the installation myself and ran into a brick wall. I managed to remove the heat shield without too much trouble but I could not loosen the rightmost bolt that holds the exhaust manifold. I tried all the tools at my disposal (which is fairly limited) so after about an hour I tightened them all back up. I also couldn't break loose the bolts that hold the exhaust flange to the cat. Both bolts were rusted shut and a shot of WD-40 on the threads didn't seem to make any difference.

Installation, Part 2: Made an appointment with Mr. Heeltoe and drove down to Mission Viejo one Friday morning. Marcus was able to get all the bolts loose and complete the header swap within about an hour ( it would have taken me half a day ). We reused the gasket between the two header pieces and between the exhaust flange and cat but used a brand new exhaust manifold gasket that I purchased from the dealer. It was pretty amazing to watch Marcus work and more amazing to talk to him about cars. He is very knowledgeable about cars in general, Hondas and Acuras more specifically. I think we're pretty fortunate to have someone like him be a vendor and a participating member. Marcus did note that he had to "pull in" the exhaust a little bit to make the connection. The header seemed to be about 1/2-inch too short. The installation went smoothly, but the results were disappointing. On our test drive we quickly determined that the flex pipe had a hole in it. It was barely perceptible at idle but as soon as throttle was applied you could definitely hear the "prrrrfffffffffffttttttttt". Marcus called it "motorboat" and it was pretty much dead on as to how it sounded. Marcus didn't have the time to swap the header back, and I didn't want to spend more money just to get back to where I started, so I kept the Topspeed header on the TSX.

The hole: I wanted to see exactly where the hole was so when the car was cold I wrapped a plastic bag all the way around the flex pipe and taped both ends. I also noticed that the header had shifted and now it appeared to be too long, it looked like it was pushing on the cat by about 1/2 to 1 - inch. It might have just appeared that way because my driveway is at a slight incline. Anyways, I had my wife start the car and tap the throttle and saw immediately the bag react to the exhaust gases leaking through the flex mesh. The bag would quickly inflate on throttle and deflate as the throttle was released and the gases were sucked back into the flex pipe. On closer inspection I noticed that the header was not perfectly aligned with the cat. At rest, the flex pipe was actually slightly bent up and to the left in order for the header to be attached properly to the cat.

The fix: I got in touch with the seller and he shipped me a replacement flex pipe (2-inch inside diameter, 6-inches long). I found a local muffler shop that also specializes in custom exhaust systems and for $95 they cut out the old flex pipe and properly aligned the header and welded in the new flex pipe. Problem solved, noise gone, jlukja very happy . On the old flex pipe you can easily see a crack in the inside bellows. The crack went practically half the circumference of the pipe. You can tell that as throttle was applied and the engine rotated slightly the movement of the engine would cause the flex pipe to flex upward, thus opening the crack. I’ll post pics once I get my computer working at home.

Impressions: I did not do a before-and-after dyno. But, my butt dyno certainly can feel the difference. The engine seems to be more willing to rev and it revs up more freely. The car also feels like it pulls a little harder. My guess would be that its worth about 7-10 HP. Once I complete a number of runs I expect the ECU to adjust to the new breathing capability of the engine and optimize performance. All in all, the performance improvement is definitely noticeable. The sound isn’t all that much different with the exception of a slight hiss at WOT. It can only be heard with the windows down and could be mistaken for air rushing through the windows at higher speeds. Not really a problem for me.

Conclusions: The complete header, initial installation, and fix cost me a little under $300, or roughly what you can buy a new DC Header for. The performance is definitely there. Although the header appears to be well made I suspect that the materials, particularly the flex pipe, were lacking. Also, it doesn't seem like my header was a perfect fit for the TSX. Having the header slightly misaligned meant that the flex pipe was already stressed when installed, even before the engine was fired up. If you do choose to go this route I would recommend that you replace the flex pipe. Your choice whether you want to do that before you install the header or after. Who knows, maybe you’ll get lucky and not have the problem at all. The ultimate cost will be less than getting a DC header and replacing the flex pipe (although I understand that DC Sports has addressed the problem). And, for those of you in California note that this header is not CARB certified so you run the risk of the SMOG station noticing this and not agreeing to smog your car. For me, I’m willing to take that chance at this time.

 

glad to hear everything work out in the end. u planning on dyno?

 

Nice write-up very detailed and helpful to others. Yea, Marcus is awesome and a great benefit to this site. Glad you got the Topspeed fixed, there is quite a lot of shock put on the header/exhaust during engine movement...and as you found, it can create havoc if things don't line up correctly.

 

Nothing an Ingalls ETD can't help with!

Glad its all working now. Topspeed + patience is a great combo.

 

are there any vendors on the site that sell topspeed headers?

 

Great write-up, Jan. Glad to hear you got everything worked out to your satisfaction. Refresh my memory. The Topspeed is the so-called "knock-off" of the DC, correct?

 

None that I'm aware of. You can find these headers mostly on e-bay.

 

My thought exactly...

 

Jan, I'm glad that you finally got it installed.

 

Yes. They look very much like the DC Sports header, two-piece design, only the Topspeed is made of stainless steel whereas the DC header is ceramic (or ceramic coated iron?)

Top Speed:

 

So am I. Considering I first got it in early March.

 

Thanks Jan. This gives me hope.

I have almost the same story/problem. I bought a used Topspeed and have a problem with the flex pipe. It was so bad that I had to take it off and put back the stock exhaust manifold. I also had a problem with the two sections not sealing properly. That will be fixed with new bolts. I ordered a replacement flex pipe and got it today. Hopefully I can find a shop that will replace it on the header and I can also enjoy this header. Maybe this week

 

Congrats on the new header Jan

I'm glad that you got everything worked out. In terms of CARB approval. You can print out the Exemption information for the DC header from the CARB website. If your smog shop says that it can't pass, then give them the paper work and say the header is CARB approved. I know it's not the DC header, but the design is identical. That's close enough in my book!

 

hmmm, i want to buy this header but i want a reliable place to buy it from

 

I gave this some thought, but from what I remember its a felony. Of course, I can just play dumb and say that the guy who sold it to me at the swapmeet said it was DC.

Seriously, though, the last time my wife's Civic got smogged (April) the guy wasn't too interested in inspecting it. This will be in my favor as my car doesn't look modified (except the obvious Comptech Icebox which I will replace with the stock lid for the inspection). I'm also 44 and a smog shop jockey wouldn't exactly look at me and think Fast & Furious. I've also been toying with the idea of reinstalling the OEM heatshield with some hammered modifications. With the heatshield on the header is, for all intents and purposes, completely hidden.

 

I was told that any muffler shop could do it. I selected a local one that advertized custom exhausts but, in reality, if they cut and weld pipe (and all muffler shops do) then its a pretty straightforward fix. Let us know how it goes.

 

Nice write up Jan and thanks for testing. I'm glad everything worked out for you in the long run too I plan on doing headers and hondata eventually but not yet and i was considering these. I only have 5k miles on my 06 now so i have plenty of time!

 

Ah, Ha. Now that's more like it! I had the flex pipe replaced today and I installed the header back. Only a slight hiss when at WOT and radio off. Much, much better. I also used 3/8" x 1 1/2" bolts with washers on both sides, lock washers and loctite to hold the two pipe section of the header together. I think no more leaks for a while!

As for gains/performance, I find it hard to detect, if any. It's just small steps. Intake, hondata, header one at a time. I'd have to drive a stock TSX to feel the difference I guess.

 

The CT Icebox is CARB compliant, but if you mean that you don't want to raise the curiosity of the tech, then I understand.

 

When installing my DC header (v1), we had to drill and torch out the bolts on the flange to the cat. They were completely and utterly seized. Things like that can really slow down an install and require a visit to a local shop, and make you feel kinda shitty. Luckily I was at a friends' house who has all the appropriate tools and we did it all there, but it just took a bit longer (more beers!) to get done.

The only thing I did to the DC Sports v1 before installing it was bring it to a welding shop to have the tack welds put in on the downstream side of the flex pipe, to solidify the area. Seems to be 100% and the sound of a hiss is only mildly noticeable at WOT only. Every other throttle position, all I hear is the Injen screaming.

Glad you got your Topspeed installed. The gains aren't SUPER noticeable but they sure are there throughout the RPM range now, eh?

 

Yes, they are noticeable. With this mod (to add to the Icebox + reflash) I think I've satisfied my need for additional power out of my 04AT.

 

That is exactly what i think i will do with my 06AT. I like the power but i want just a tad bit more. I actually like the surge of power on the 06 compared to my 04 when you hit 6100 RPM's and i kind of don't want to loose that but i guess if the car was overall faster i could live with the easier VTEC transition

Glad you've accomplished what you were looking for jan

 

Icebox made a fairly minimal difference on my 06AT, but both the Pulleys and DC Header made significant/noticeable gains.

 

nice write up!!

 

Over the past few months I've been hearing what sounds like another hole in the header. It sounds just like the cracked flex pipe I previously had only not nearly as loud. I can hear it a little when the car starts up cold, and it almost goes away completely when the car warms up. However, even when warm, I can hear it again and louder when applying throttle, particularly at WOT. I did a detailed inspection and found nothing. I took it to the muffler shop and they couldn't find anything either. They said they can't hear anything different but I know what I hear. When I described what I heard to the tech he suggested that the connection between the header and the exhaust manifold had loosened. He suggested I back out the bolts and retighten to see if the problem goes away.

My questions are:
1. Should I replace the gasket if I loosen the bolts or just retighten with the same gasket?
2. Can I get the header completely off the bolts (and replace the gasket) without removing the hangers? (i.e. is there enough play in the hangers for this?)
3. Anyone have a good method for checking the exhaust manifold gasket area for leaks? I wrapped the flexpipe with a plastic bag to see if it inflated (it didn't). With the engine running I ran my hand all around the exhaust piping, trying to feel for telltale puffs of hot air (no puffs). I heard you can use an open flame that would flicker when placed next to a leak but I don't feel comfortable putting an open flame near the exhaust manifold. First, I cant reach up far enough without burning my arm and, second, too many oils and such under there that might catch fire. I'm open to ideas.

 

Try to look for signs of exhaust leaks around the top and bottom of the manifold. You may need to use an angled mirror in tight areas. It usually leaves a black mark where it leaks. I had a header gasket leak on my Civic and ended up replacing the metal gasket.

 

Thanks for the glowing comment in the OP. I try

Also check around the manifold flange. Different grades of steel will expand and contract with temp, and it could be that some of the nuts have worked loose and now there is an intermittent leak. I'd be happy to snug them up if you wanna stop by.

 

My DC started making the EXACT sounds in the same situations as you describe, and it wasn't soon after that it sounded like a Harley when I was on the go-pedal. The problem was the flex pipe separated from its solid flange. IE: The mesh came loose from the solid metal portion of the flex pipe.

This is a problem with the length of the header being about 1/4" too short, and I had it fixed at a local muffler shop for about $75 + $30 for the Vibrant stainless flex pipe (6" overall length, 4" flex section, 2" diameter). They cut the old pipe out and welded the new one in such that it gave about 1/4" to 3/8" extra length, and the problem was solved 100%.

 

Exactly what I have done too. Go in here for more details...
http://www..com/forums/showthread.php?t=26663

 

JTso,
I went over every square inch of the header and the three gaskets and I did use a mirror to get a good look (from the top and from underheath). No telltale soot marks anywhere I could see. I also inspected all the welds just to make sure they were OK.

Curls, chuson,
I've already replaced the flexpipe with a double braided stainless steel one. The muffler shop also aligned the header better when they did the flex pipe swap.

Marcus,
Yeah, my thinking also is that its got to be where the header meets the exhaust manifold. Logically its the only place for me to not get a great look and a difficult place to test for airleaks. I'll try to tighten the bolts. If that doesn't work I'll see if I can back them out and retighten again. If no luck I may swap gaskets. If no luck still then I may have to come down and see you to see if we can troubleshoot it. My registration renews in December so I'm going to need to fix this before I take it in for the smog test.

 

Update... Well, I replaced the exhaust manifold gasket and the sound has diminished, but its still there. I'm at a loss for what else it could be.