OBX header
- Thread starter Hy8us
- Start date
Ok, Ok...Lets see if I got this right.
The 4-1 OBX headers gives out more power than the 4-2-1 on our car/p5.
W/ the 4-1 headers I will have to remove one of the 2 cats. Which is the first cat after the stock headers right?
Then I still keep the 2nd cat where the 2nd o2 sensor is located. Right?
Ok, so does the obx headers came with the 1st o2 sensor hole? Or do I have to drill a hole on there?
Will the OBX headers connects on to the stock 2nd cat w/ no modification?
Will this mod void the warranty?
I don't see any cutting/splicing the o2 wires. This is good because I dont want to cut/splice any wires on my car.
Most of the p5 owners that I've talked to w/ the OBX headers told me that the difference in power is very noticeable. One guy even mentioned that its like night and day. On a sohc vtec civic, the headers dont really make that much difference and same goes for the 323 w/ BP and headers, you can notice it but not big of a difference.
Sorry fellas but I've been debating about this headers. Thanks.
The 4-1 OBX headers gives out more power than the 4-2-1 on our car/p5.
W/ the 4-1 headers I will have to remove one of the 2 cats. Which is the first cat after the stock headers right?
Then I still keep the 2nd cat where the 2nd o2 sensor is located. Right?
Ok, so does the obx headers came with the 1st o2 sensor hole? Or do I have to drill a hole on there?
Will the OBX headers connects on to the stock 2nd cat w/ no modification?
Will this mod void the warranty?
I don't see any cutting/splicing the o2 wires. This is good because I dont want to cut/splice any wires on my car.
Most of the p5 owners that I've talked to w/ the OBX headers told me that the difference in power is very noticeable. One guy even mentioned that its like night and day. On a sohc vtec civic, the headers dont really make that much difference and same goes for the 323 w/ BP and headers, you can notice it but not big of a difference.
Sorry fellas but I've been debating about this headers. Thanks.
The first cat is right after the manifold. That one is replaced with the header. The second Cat is further along the exhaust, nothing to worry about.
The first O2 sensor is near the top of the header, no problem.
The second O2 sensor is near the bottom of the header, and it will freak out because you no longer have the 1st Cat. Using the non-fouler will get the second O2 sensor to read a lower value, within it's acceptable range as though the 1st cat was still there.
Most headers now have 2 O2 sensor bungs, the OBX and Tsudo are like this. Just look at a picture of them, they will have the EGR bung, and 2 O2 sensor bungs.
The 4-1 headers will give you a little more power up top, 4500+rpm, but I still think it's minor. I get more power from simply turning the AC off.
The first O2 sensor is near the top of the header, no problem.
The second O2 sensor is near the bottom of the header, and it will freak out because you no longer have the 1st Cat. Using the non-fouler will get the second O2 sensor to read a lower value, within it's acceptable range as though the 1st cat was still there.
Most headers now have 2 O2 sensor bungs, the OBX and Tsudo are like this. Just look at a picture of them, they will have the EGR bung, and 2 O2 sensor bungs.
The 4-1 headers will give you a little more power up top, 4500+rpm, but I still think it's minor. I get more power from simply turning the AC off.
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- protege5 2002
I notice a gain in power when i installed my obx header.
02PROTEGE2.0
Member
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- 1999 Audi A4 1.8t quattro manual
i noticed a strong gain with my ractive header... most of u have probably heard me rant on why i think its better... (4 tubes all the way to the mid pipe)
HOWEVER when i installed my RB axle back it seems to have gained top end and lost some low end... maybe its just my mind playing tricks on me,...
(used to the car only being loud when its making alot of power... new muffler equals louder earlier...)
but none the less... header i think is the best bolt on for the money... i got mine for 75 bucks shipped brand new!!! it was on ebay with no reserve and i was the highest bidder!!!! yay!
i think im gonna need a new mid pipe next...
HOWEVER when i installed my RB axle back it seems to have gained top end and lost some low end... maybe its just my mind playing tricks on me,...
(used to the car only being loud when its making alot of power... new muffler equals louder earlier...)
but none the less... header i think is the best bolt on for the money... i got mine for 75 bucks shipped brand new!!! it was on ebay with no reserve and i was the highest bidder!!!! yay!
i think im gonna need a new mid pipe next...
Raven Hawk
Member
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- 2003 MP5
Just put my OBX on this weekend after getting it back from the ceramic coaters. It wasn't all that hard to install, but it would have been nice to have a new donut gasket. I've got a new donut on order and I'll put it in with my midpipe install.
After the install, it seems a little weaker at the lower end and a little quicker at the higher end.
After the install, it seems a little weaker at the lower end and a little quicker at the higher end.
Raven Hawk said:
Mine too, I'm dissapointed enough that I might go back to stock. I can't drive around at wide-open-throttle all day just to keep up in traffic.
Anyone know of a good way to get low-mid power? Still sux that there is no supercharger... Cams maybe?
thrasher said:
a 4-2-1 header should yield better low and mid power compared to a 4-1 which usually gives higher rpm power. dont forget that when you lose the cat you are losing a restriction that can actually create power under certain circumstances. N/A cars like a bit more back pressure than forced induction.
Raven Hawk
Member
- :
- 2003 MP5
thrasher said:
I believe that it's been said before, but an underdrive pulley can get you more at the low end. I'm hoping to get mine installed soon, but the jackasses that put my last set of tires on over torqued my lugs. I can't get them off with a low end impact wrench (100 ft/lb). Time to go back to the shop and ask them to loosen and hand torque it up.
S_C_I_P_I_O79
Member
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- 03 Pro ES 5spd
Ditto on the UDP. I installed my RR pulley 10 days ago and did gain some low end that I MAY had lost since my OBX header install last year. Actually the gains from the pulley seems throughout the range. Plus way easy for the install compared to the header (had big time EGR alignment issues). 
My EGR nut wouldn't go back on either. Just didn't line up right. I had to take off all the bolts at the head and down below at the exhaust, move the header around.... finally got it. That is one non-flexible little tube, PITA!
Now I can't get my rear motor-mount nuts off, not even with my impact and PB-blaster. Might actually have to go to the shop for this one. (ughdance)
As for the UDP, I'm not so sure I want my accessories to work any less, especially the AC. I hate being hot.
Now I can't get my rear motor-mount nuts off, not even with my impact and PB-blaster. Might actually have to go to the shop for this one. (ughdance)
As for the UDP, I'm not so sure I want my accessories to work any less, especially the AC. I hate being hot.
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Raven Hawk
Member
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- 2003 MP5
thrasher said:
I had issues with the EGR nut also. I was able to solve the problem by tightening down the two right most header bolts (top and bottom) then slipping the EGR bolt over the threads. It didn't work like a charm, but well enough for me to get it back on. It was a PITA, though.
S_C_I_P_I_O79
Member
- :
- 03 Pro ES 5spd
To get my EGR to line up I removed the EGR pipe from the car and bent it a little at a time (by putting the spot I wanted to bend through the closed end of a good sized wrench and putting the other end of the pipe under my armpit and pulling on the open end of the wrench using its leverage to bend the pipe) until it lined up. It was tuff and took la lot longer than I expected.
As for the UDP and its effect on A/C, I have not noticed any impact. My Scangauge II measures between 13.7 VDC and 14.1 VDC with my A/C on or off, at low and high speeds. There is a jump in voltage (~0.2 VDC) when the A/C is turned on or off but the voltage returns to where it was within a few seconds. My stock sound 'system' shows no real impact. I do have a groundwire kit installed so that may help.
As for the UDP and its effect on A/C, I have not noticed any impact. My Scangauge II measures between 13.7 VDC and 14.1 VDC with my A/C on or off, at low and high speeds. There is a jump in voltage (~0.2 VDC) when the A/C is turned on or off but the voltage returns to where it was within a few seconds. My stock sound 'system' shows no real impact. I do have a groundwire kit installed so that may help.
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