Schnell Headers on 986 with Stock Exhaust

[rule1]

I have had these same headers on since the first of july and have still not had a CEL, on my 2000.

[Cloudsurfer]

What did you do about the second O2 sensors? Relocate behind the secondary cats, use a de-fouler, etc?

Patrick

Originally Posted by rule1

I have had these same headers on since the first of july and have still not had a CEL, on my 2000.

[rule1]

No these headers have 4 o2 bungs. 2 per header. I did not relocate anything.

[blinkwatt]

Originally Posted by rule1

I have had these same headers on since the first of july and have still not had a CEL, on my 2000.

How many miles ago was that?

This was from Maxspeed's ebay auction

http://cgi.ebay.com/ebaymotors/Porsche-Boxster-986-2-5L-2-7L-3-2L-Performance-HEADERS_W0QQcmdZViewItemQQcategoryZ33631QQihZ011QQ itemZ320148798294QQrdZ1QQsspagenameZWDVW

"Q- On the 2.7L & 3.2L will these headers trigger C.E.L (Check Engine Light)?

A- As mentionned above we have tested these headerson a 2002 2.7L Boxster and we had the C.E.L light came on 3 times always with the same code that has occured on a 3000 Mile testing , this is caused by the deletion of the primary cats, in return they are noticeable power gains and improved sound. So yes on the 2.7L and 3.2L the C.E.L will possibly come on.

Q-What can be done to resolve the C.E.L ?

A- Two things can be done, either you purchase a Scanner to erase the light when it comes on. Thats what I do I purchased a nice scanner online and its a great tool to have. Or you will need to relocate the 2nd O2 sensor right after the 2nd set of cats that also involves extending the wiring on the O2 sensors. This is the permanent solution. We can help you with this solution just ask we have the O2 weld sensor bungs to relocate.

Q- How much Hp/Torque Gains?

A- We will do our best to do a Dyno run soon we will post results as soon as we have then, we expect a 10-15HP gain with these headers, thats our opinion not a fact. "

Wow,those aren't the answers you want to hear about a product.

[rule1]

Again go to maxspeeds full exhaust ad for the dyno results. I have put about 2000 miles since the install and no CEL. I have muffler,headers,and EVO intake and pulled 209 HP to the rear wheels on Imagine Auto's dyno.

[blinkwatt]

Are you Jarret R of MO that's in the pic?

[rule1]

Yes, thats my white boxster.

[Cloudsurfer]

4 bungs in a non catted header do nothing for you. The engine ECU cares about the first set, as it uses that to control the fuel mixture going into the engine. The second set are there for OBD II diagnostics to detect catalytic failure (or in this case, cat removal). This is why you should get a CEL if you simply plug all 4 into the non catted header. You can possibly get by with a spark plug defouler, which moves the tip of the O2 sensor out of the exhaust flow somewhat and on some cars will cause the secondary O2s to read "normal" as if they are seeing catalyzed exhaust.

Relocating the secondary set to after the secondary cats may work, but you are going to change the impedance of the circuit with the added wiring. In my case, I also do not have secondary cats as I have the FabSpeed system.

I am VERY surprised you have not gotten a CEL on your car yet.

Patrick

i have a 99, will i ever receive A CEL, from adding after market headers??

[Adam]

Originally Posted by bmwm750

4 bungs in a non catted header do nothing for you. The engine ECU cares about the first set, as it uses that to control the fuel mixture going into the engine. The second set are there for OBD II diagnostics to detect catalytic failure (or in this case, cat removal). This is why you should get a CEL if you simply plug all 4 into the non catted header. You can possibly get by with a spark plug defouler, which moves the tip of the O2 sensor out of the exhaust flow somewhat and on some cars will cause the secondary O2s to read "normal" as if they are seeing catalyzed exhaust.

Relocating the secondary set to after the secondary cats may work, but you are going to change the impedance of the circuit with the added wiring. In my case, I also do not have secondary cats as I have the FabSpeed system.

I am VERY surprised you have not gotten a CEL on your car yet.

Patrick

^ He is right on the $$$. The only header going on my car is the faspeed with the integrated cats. Hey, they are expensive, but I don't want to have to clear a code every other day either.