OBX RX8 Header
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OBX RX8 Header
OBX Header
http://cgi.ebay.com/ebaymotors/OBX-E...04383069QQrdZ1
I know OBX makes pretty crappy stuff, but its a cheap header compared to what is out there.
Any opinions if it would make any power gains or is it worthless?
http://cgi.ebay.com/ebaymotors/OBX-E...04383069QQrdZ1
I know OBX makes pretty crappy stuff, but its a cheap header compared to what is out there.
Any opinions if it would make any power gains or is it worthless?
always preoccupied.
Joined: Feb 2005
Posts: 827
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From: Kirkland, WA
It's probably just a copy of one of the $1000 ones. That's what these companies do, buy one, make a mold or design for replication, sell the expensive one, and begin production on their knockoff versions. Shouldn't be a change in power if this is the case, change in quality, though, is another story. Lots of times these cheap ebay exhaust parts use thin walled tubing.
SC 300HP!!
Joined: Dec 2004
Posts: 3,182
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From: Singapore, North-east
Originally Posted by Jabberwock
I thought some of the $1000+ header make a little more than 2-3hp depending on design.
Any experts know if the OBX Header design would make much of a hp or torque difference.
Any experts know if the OBX Header design would make much of a hp or torque difference.
10 horses for the 6mt, 5 horses for the 4AT and 5MT
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From: QLD .au
Originally Posted by expo1
Well if the $1,000 header's only give a 2-3 HP boost whan can you expect from a $287 one??
You get what you pay for
You get what you pay for
Bummed, but bring on OU!
Joined: Sep 2003
Posts: 2,036
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From: Charleston, SC
Originally Posted by coupe07
an authentic header from japan will give u 5-10 horses.......
10 horses for the 6mt, 5 horses for the 4AT and 5MT
10 horses for the 6mt, 5 horses for the 4AT and 5MT
$43 for s/h? Seems a little high. A bit more handling than shipping I'd bet :p
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Joined: Feb 2004
Posts: 1,802
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From: QLD .au
Originally Posted by therm8
i'd like to see that...then I might believe it. Equal length headers won't give you such gains on the renesis. And all the headers I've seen from Japan were equal length.
$43 for s/h? Seems a little high. A bit more handling than shipping I'd bet :p
$43 for s/h? Seems a little high. A bit more handling than shipping I'd bet :p
the knightsport ones look far from equal but seperate the centre ports;
the obx ones look like the re amemyia ones and look equal length;
the FEED have longer runners and are also fairly equal in length by the look.
Bummed, but bring on OU!
Joined: Sep 2003
Posts: 2,036
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From: Charleston, SC
They may not all be equal length, but all three runners collect at the same point, which doesn't make sense harmonically when you consider the siamesed center port. It's runner should collect further down theoretically to make the most of the pulse tuning. Knightsport looked like they were heading the right direction.
This is from a much older discussion: (there was a much, much older one but I can't find it)
for $330 it may be worth a shot, at least you might have something to experiment on when there are little to no gains. The problem with the "ideal" harmonic design is that it would take up alot of space, and space is hard to come by under the car.
This is from a much older discussion: (there was a much, much older one but I can't find it)
Originally Posted by rotarygod
Racing Beat played with a split center runner and found that it didn't do any better than the conventional 3 runner header. That is really strange to me. They did say that the header designs that they tested did about 4-5 hp more but only at the peak point. I still need to build my header design to see if it has any merit. It might not work but I won't know until I try it. The 2 outer runners get collected at the same length. The center runner is 50% longer and connects downstream of them. Off of this center runner is a dead leg pipe to nowhere that is the same length as the outer pipes but blocked off. This is purely for resonance. I have no idea if it would work on the Renesis but on older 4 cylinder piston engines that had siamesed center runners, they did this on the race cars. The original mini was one such vehicle. It worked there. One way to find out I guess.
I do have another thought as to why headers aren't doing much on this engine. Part of it could do with the fact that we have no overlap and therefore no scavenging that can help pull in more intake charge. The other thought is that the exhaust ports right now just don't flow any better than even the stock exhaust manifold and that any increase in flow in the exhaust system really won't do much. I really wonder how a set of headers would do on a ported engine?
I do have another thought as to why headers aren't doing much on this engine. Part of it could do with the fact that we have no overlap and therefore no scavenging that can help pull in more intake charge. The other thought is that the exhaust ports right now just don't flow any better than even the stock exhaust manifold and that any increase in flow in the exhaust system really won't do much. I really wonder how a set of headers would do on a ported engine?
always preoccupied.
Joined: Feb 2005
Posts: 827
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From: Kirkland, WA
$249 + 32 in this auction that was just started today
http://cgi.ebay.com/ebaymotors/OBX-R...spagenameZWDVW
Wonder how long before all the car part ebay power sellers are selling them and having a battle for the lowest overall price. Should be interesting.
http://cgi.ebay.com/ebaymotors/OBX-R...spagenameZWDVW
Wonder how long before all the car part ebay power sellers are selling them and having a battle for the lowest overall price. Should be interesting.
always preoccupied.
Joined: Feb 2005
Posts: 827
Likes: 1
From: Kirkland, WA
I'm actually thinking about buying it to give it a shot... I'm going to get a catback and midpipe first, though, and will probably hold onto them until I get the header (if I decide to) so I can do the whole install at once.
Oil Injection
Joined: Feb 2005
Posts: 1,672
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From: Orlando, FL
Originally Posted by tuj
The OBX headers for the Miata were initially much maligned until people realized they were really pretty decent, and about half the price of the competitors.
I had one on my 99 miata, I got it for 100 used.
The quality of the header was great, nice welds, nice thick tubing, it was all stainless steel with ceramic coating, looked good, smooth bends, nice cut flange, ect.
I would say they make a good product.
The problem with the OBX stuff was always the FIT, they never fit quite right, rather than bend the tubing on the header, we could always bend the firewall a bit, or make a small dent in a rail, whatever, to make the header fit.
The fit was never really bad, off by maby 1/8-1/4 inch....so it wasnt much work.
It would bolt up fine, just that it would rattle agaisnt the frame or firewall, causeing noise and vibrations. So if you dont mind a little time to knock it in place, it isnt a big deal IMO.
My concern with the RX8 would be the placement of that O2 sensor, in just 1 of the pipes, not the colector, and the fact that the exhaust on the motor is VERY hot, and you wouldnt want it as close to the body/frame as you might try with a piston engine.
I would get one and ceramic coat it and/or heat wrap it...just to be safe.