Anyone using OBX longtubes?
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,093
Likes: 820
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
Anyone using OBX longtubes?
If so, would you recommend buying them? How is fitment, access to spark plugs? I want longtubes, but can't afford to spend what ARH or SW cost, new.
Specifically asking about LT1/4 cars.
Also, Merry Christmas to all
Specifically asking about LT1/4 cars.
Also, Merry Christmas to all
Last edited by 1993C4LT1; Dec 25, 2025 at 03:54 PM.
Race Director
Joined: Oct 2012
Posts: 17,388
Likes: 6,530
From: Melbourne, FL
I was looking at them and decided against them. There was not much positive experience with them, and in the end I decided to use cheaper ones that I knew would need some work to get them fitted.
I'm partially through that install as we speak.
I'm partially through that install as we speak.
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
The installation took some work.
-A few header bolts holes were not perfect, so I had to take a round file to open up the holes to get the header bolts to align.
-The air pump fitting on the passenger side did not line up at all.
-To install the alternator and AC support brackets, couple of header tubes needed to be dented to fit.
-The last header bolt on the driver side, closest to the driver is hard to access.
Other than that, once they were installed, I'm happy with them.
-A few header bolts holes were not perfect, so I had to take a round file to open up the holes to get the header bolts to align.
-The air pump fitting on the passenger side did not line up at all.
-To install the alternator and AC support brackets, couple of header tubes needed to be dented to fit.
-The last header bolt on the driver side, closest to the driver is hard to access.
Other than that, once they were installed, I'm happy with them.
Instructor
Joined: Apr 2022
Posts: 181
Likes: 118
From: Oregon
I bought a set that looked exactly like the obx (probably the same manufacturer. Install was a nightmare. Bad fitment, required mini starter, had to dent tubes in a couple of places as well as adding heat shielding in multiple areas that I thought they were too close to other items.
I would not want to repeat this job and wish I had never done it.
I would not want to repeat this job and wish I had never done it.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,093
Likes: 820
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
The installation took some work.
-A few header bolts holes were not perfect, so I had to take a round file to open up the holes to get the header bolts to align.
-The air pump fitting on the passenger side did not line up at all.
-To install the alternator and AC support brackets, couple of header tubes needed to be dented to fit.
-The last header bolt on the driver side, closest to the driver is hard to access.
Other than that, once they were installed, I'm happy with them.
-A few header bolts holes were not perfect, so I had to take a round file to open up the holes to get the header bolts to align.
-The air pump fitting on the passenger side did not line up at all.
-To install the alternator and AC support brackets, couple of header tubes needed to be dented to fit.
-The last header bolt on the driver side, closest to the driver is hard to access.
Other than that, once they were installed, I'm happy with them.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,093
Likes: 820
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
I bought a set that looked exactly like the obx (probably the same manufacturer. Install was a nightmare. Bad fitment, required mini starter, had to dent tubes in a couple of places as well as adding heat shielding in multiple areas that I thought they were too close to other items.
I would not want to repeat this job and wish I had never done it.
I would not want to repeat this job and wish I had never done it.
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
It was a few years ago, but I'm pretty sure the header gasket were the Cometic fiber gaskets. The header bolts were the 3/8" ones with the allen head in the middle, and the ones for the alternator/ A/C brackets were longer allen head bolts, and spacers from my local hardware store.
Longer bolts and spacers can be seen here.
Longer bolts and spacers can be seen here.
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Race Director
Joined: Oct 2012
Posts: 17,388
Likes: 6,530
From: Melbourne, FL
I bought copper (copper outsides and fiber middle layer) gaskets for mine, and ARP bolts. I will probably need to source a longer bolt and spacer for the dipstick (or switch to the flexible stainless movable type), and the AC compressor support bolt.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,093
Likes: 820
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
Thanks guys
I've only ever done a longtube header swap on my other car. A Cooper s r53 jcw. I bought the best header money can buy, because it's only 1 bank of cylinders, so half the price lol. And that was such an easy swap.
I've only ever done a longtube header swap on my other car. A Cooper s r53 jcw. I bought the best header money can buy, because it's only 1 bank of cylinders, so half the price lol. And that was such an easy swap.
Race Director
Joined: Oct 2012
Posts: 17,388
Likes: 6,530
From: Melbourne, FL
Don't expect this install to be anywhere near as easy. My exhaust manifold bolts have been the easiest bolts I've had to deal with this far, everything else is a pain in the ***, lol. The driver's side connection to the exhaust I snapped 2/3 bolts and cut the last one. The manifold to cat pipes is basically the same deal, basically broke all the bolts off vs removing them. I deleted the entire EGR and AIR system to make my life easier so I could just cut most of that off. The AIR tubes are basically welded to the manifolds by now lol.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,093
Likes: 820
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
I plan to get rid of the AIR as well and EGR. Yeah, trust me, I know it won't be as easy. I removed the exhaust when I was removing the trans years back. Even that isn't easy, lol.
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
Same set as mine. I did mine up on jack stands like you, using a car creeper. The passenger side went in easy, driver side has to dent the tubes to install the supports. Hopefully your bolt holes will align better than mine.
Race Director
Joined: Oct 2012
Posts: 17,388
Likes: 6,530
From: Melbourne, FL