N/A Exhaust Manifold Options

Post by **bigdaddylee82** » 08 Jan 2012, 21:05

I've read the posts by Ozark Lee, and Cn90 about the OBX and OEM replacement exhaust manifolds for the 2.4L non-turbo. I've found a random OBX manifold or two for sale at a couple online retailers, and I really don't want to fork out the $$ for OEM. There's a handful of new stainless manifolds on fleabay too, a couple can be had, shipped to me for around $150-$180.

One looks a lot like the OBX and claims to be a "stainless racing header" the other slightly cheaper, also stainless "tig welded in Estonia." I'd wager either are better than what I've got now.

Scouring the forums, only reviews I've found have been for OBX, some good some not.

Wouldn't be the first time I've been a guinea pig, but at least 4 of the "Estonian" headers have been sold, so I was hoping for some feedback from anyone that might by chance have bought one and be a forum member too. Snowballs chance. Anyone know a anyone with one of the eBay manifolds, thoughts, impressions, anecdotal even?

Thanks!

- Lee

Post by **Matty Moo** » 08 Jan 2012, 22:51

One of my good friends has the OBX unit on his 98 na s70, him and I put it on. It's surprisingly nice and very well made.

I have an OBX system on my 96 wagon. I like it, and it's solid.

My only complaint about OBX is their customer service, which based on my experience is somewhat terrible. It took me over two months to attempt to get some clamps from them. Never did get the right clamps and they aren't too hip on communication.

They sell good stuff for the money though.

turbozutek · Post by **turbozutek** » 09 Jan 2012, 03:15

Some notes about 'Made in Estonia': I have to say that Estonia is actually well known for its metalwork and welding. Estonian fabrication is well regarded throughout Europe.

For the budget market, having metalwork fabricated and assembled in Estonia makes perfect sense and a quality product should result.

Chris...

Post by **bigdaddylee82** » 16 Feb 2012, 21:39

After a lot of shopping, looking, and researching I wound up going with a completely different "brand." I came so close to just pulling the trigger on an OBX a few times, and while installing mine there were a few times I was kicking myself for not going with something that at least had a reputation. Knowing what I know now, I'd probably still go the route I did, I'd just do a few things different from the start.

I wound up with a DNA Motoring exhaust manifold. I can't find Volvo parts on their website, but they do sell the manifolds through their eBay store, and that's where I got mine, $149.99 shipped to my door, hardware, and gaskets included. 304 Stainless Steel, CNC machined flanges, 1-1/2" primaries, 2-1/2" collector, and TIG welded, not bad for the price. DNA Motoring has a decent reputation with the Subaru crowd, and they're a forum sponsor/vendor on NASIOC.com, I read a lot of reviews/guides/etc. of various other products of theirs before making my purchase

: P2090181.JPG (154.98 KiB) Viewed 5958 times

Old Vs. New

: P2090140.JPG (153.31 KiB) Viewed 5958 times

There's some good, and not so good things with the exhaust manifold, for the most part it's good.

The welds are excellent.

: P2090153.JPG (175.62 KiB) Viewed 5958 times

: P2090158.JPG (163.02 KiB) Viewed 5958 times

The exhaust ports are physically smaller, and pretty randomly sized, compared to the factory manifold.

: P2090144.JPG (181.15 KiB) Viewed 5958 times

The connection to the exhaust pipe is however, roughly the same size to slightly larger than factory.

: P2090146.JPG (173.76 KiB) Viewed 5958 times

Comes with hardware and gaskets.

: P2090164.JPG (138.3 KiB) Viewed 5958 times

: P2090160.JPG (181.64 KiB) Viewed 5958 times

However, the hardware is cheap junk, that doesn't all fit (nuts for head studs were way too big), and my "donut" gasket came to me creased with the metal outer layers separating from the inner material.

: P2090187.JPG (157.46 KiB) Viewed 5958 times

: P2090163.JPG (151.22 KiB) Viewed 5958 times

I used copious amounts of Permatex Copper to help make up for the gasket issue, and alleviate any possibility of leaks.

: P2090172.JPG (157.22 KiB) Viewed 5958 times

: P2090173.JPG (152.27 KiB) Viewed 5958 times

: P2090175.JPG (156.46 KiB) Viewed 5958 times

The "CNC'd" flanges are all much thicker than stock, and they must actually have been machined, because the head flange is as straight as the straightest thing I had to gauge it with (carpenter's square).

: P2090167.JPG (154.07 KiB) Viewed 5958 times

: P2090169.JPG (116.57 KiB) Viewed 5958 times

: P2090150.JPG (154 KiB) Viewed 5958 times

What DNA Motoring advertises as an "O2 sensor insertion" has the same threads as the factory EGR tube, and with some modifications to the tube can be made to work. This was quite frustrating, the bung for the EGR is turned about 30 degrees towards the firewall on the DNA manifold Vs. parallel with the engine on the stock manifold. This made it very difficult to attach the tube from the manifold to the EGR valve. The tube had to be removed too many times to count and "tweaked" just a bit each time, to finally get it to fit. Picture below shows just how much "tweaking" was required.

: P2090183.JPG (139.79 KiB) Viewed 5958 times

: P2090189.JPG (168.43 KiB) Viewed 5958 times

The final frustration was an exhaust leak at the joint between the manifold and exhaust pipe. I assumed that because the donut gasket had a crease in it, that it was the source of my leak. After driving a couple days, I decided to re-torque all of the fasteners, since they'd now been through a few heat cycles. When attempting to torque the nuts/studs at the donut gasket, the nuts simply turned in place. The nuts no longer engaged the threads on the stud. My assumption was the heat caused the threads on the super cheap nuts to fail. This lead to several frustrating hours of removing nuts that just turned in place, and ruining the studs in the process, all while the manifold was still attached to the car.

My solution was some grade 5 bolts/lock washers and some jam nuts. Thankfully the holes for the studs in the manifold are threaded through, so I could insert the bolt from the back/bottom side of the manifold, and the put the jam nuts on the bolts from the top side. I'm a week into driving with this "fix" and so far so good.

: P2160201.JPG (164.63 KiB) Viewed 5958 times

The manifold itself is quality, the hardware is what sucks. I wound up reusing my original head stud nuts, and purchasing new nuts and bolts for the manifold. Had I had quality hardware from the start I wouldn't have had near the frustration that I had. Deleting the EGR would have helped alleviate just about all other frustration I had with the manifold. I must say that the customer service at DNA Motoring is top notch too. I wrote them an email describing how one of my gaskets was bent/defective, before I realized the real issue was the nuts. In my email I asked simply for a new donut gasket. They said "sure no problem," what arrived from them a few days later was a whole new hardware and gasket "kit" i.e. both gaskets and all the nuts/studs that come with the manifold. Unfortunately the new nuts are just like the original, too big, but I was pleased that they thought enough of their customer to just send me all new hardware and gaskets.

So to sum it all up, for the price, it's a great manifold. Just source your own hardware elsewhere.

- Lee

mrwillie · Post by **mrwillie** » 17 Feb 2012, 21:52

Looks good, Lee!!! How does the car feel so far?? And when do I get my egr valve??

Jus' joking....it looks real good. Is it much louder than stock?? And did you change anything else in the exhaust?

turbozutek · Post by **turbozutek** » 18 Feb 2012, 12:32

I don't like the look of that bore reduction on the cylinder exhaust outlets one bit. It could just be the pictures, but it looks like you lose a considerable circumference on the ports there?

Did you measure OEM against the new one at all? I'd be interested in the difference in mm's

Chris...

Post by **bigdaddylee82** » 18 Feb 2012, 16:59

mrwillie wrote:Looks good, Lee!!! How does the car feel so far?? And when do I get my egr valve??

Jus' joking....it looks real good. Is it much louder than stock?? And did you change anything else in the exhaust?

Feels, no different, smells a lot better though.

Only other thing I replaced in the exhaust was the pre-cat O2 sensor, so in reality no I didn't change anything else, and it doesn't sound any different. I purchased pipe and a muffler long ago to delete the cat and run 2-1/2" from the header back. Never got motivated, then moved 780 miles away from a large portion of my tools.

Never did go through the box of parts, I think I've got a spare EGR. Email me your address and I'll get it your way.

turbozutek wrote:I don't like the look of that bore reduction on the cylinder exhaust outlets one bit. It could just be the pictures, but it looks like you lose a considerable circumference on the ports there?

Did you measure OEM against the new one at all? I'd be interested in the difference in mm's

Chris...

Meh, it is what it is. I have no delusions of this being a power house, there is no discernible difference in performance. I was looking for the cheapest way to reliably fix my leaking flex pipe and this fit the bill nicely. I actually did measure and write down all of the port sizes length/width on a piece of cardboard while waiting on the Coppercoat to get tacky. I'll go dig around and see if I can find them.

- Lee