I'm sure some of you guys are eagerly awaiting to hear the latest on this project so.. I recieved my oem 2000 fed-spec headers a few days ago and I also ordered my Y-pipe from WSP yesterday (2000 fed spec pipe). So once my WSP Y-pipe comes in I will be installing the 2000 headers and the WSP Y-pipe and shortly after that I will have some dyno results.


A question to some of the guys who converted there 2000-2001 cali-spec max's to fed-spec. I recall one of you guys stated that if you leave the o2 sensors off(rather then relocated) all it will do is trigger a check engine light? If that is the only problem I will just un-plug my o2 sensors and remove the check engine light bulb from my gauge cluster. Let me know what guys think of that please

 

i have no clue but i'm ready to see the dyno results

 

First, I would have the 2000 OEM Fed spec "headers" cleaned up by a good machine shop. You can probably remove quite a bit of material to help let that 35VQ breath. At least it will give you something to do until the Y-pipe shows up and it's easy since they're already off the car.

Second, do NOT mess with the FRONT 02-sensors. These allow your ECU to adjust your Air/Fuel ratio. The rear 2-sensors are used to tell if the FRONTs fail, but if they are too far out of range they will trigger a code. You might look/try some 02-sensor "imitators" I've seen in the Summit Catalog so you can still have an operational MIL(Malfunction Indicator Lamp). Of course they are for Camaros, Mustangs, etc.., but they may work with a little tweaking. It's probably a good idea to invest in a OBD-II scan tool if you don't already have one. It will most likely save a trip or two to the dealer.

Good Luck! Can't wait to see what happens on the dyno.

 

Don in Texas removed a lot of material on his maxima and saw a 1hp gain so I am not going to botehr going that route.

I am going to definatly keep the front o2 sensors on my car but if the rear ones are not going to effect the drivability of the car I may just leave them off. If the rear o2 sensors effect the drivability of the car I will mount them in my B-pipe right behind the main cat.

 

Why don't you place the O2 after the cat?

 

Exactly, Kev. That's what Desert Pearl did and it worked out real well for him.

 

Ahem The question remains will my car still drive fine with the rear o2 sensors off of the car?

 

No freakin way Ethan. They are there to relay info to you car's computer. I screwed 2 of them up in Stang, and it ran like CRAP for a month, till I figured out my O2's were fried..... That is NOT a good idea..!

 

I guess my question is, what's your objection to mounting them behind the cat?

 

it would kinda throw off the ECU as far as reading correct fuel/air mixure levels...but it would run...but for a long time? uh...i don't know..

 

It tricks the the sensors and ecu into thinking everything is ok and relyas the proper info to the ecu.

Thanks for the info Irvine and otehrs, Iwill have teh sensors mounted behind my cat that. I just bought 2 K&N o2 sensor bungs so now all I need to do is have a shop do a little bit of welding.

I'm planing on buying 2 o2 sensors from a 2000 fed spec max(the ones that mount in the S pipe) that way the wires will be long enough. That should work right? Maybe I can get these cheap from a junkyard..lets see.

 

Cheap-o... just extend the wires.

And don't you "ahem" me!

 

Ahem How would I go about extending the wires?
BTW check your PM's.

 

14 gauge wires.

Replied to your PM.

 

And solder I amagine?

 

Ethan I would say that would be a potentially bad idea. Why not just mount them where they belong? I have heard the precats are only for use when the car is cold and that the main cat still does all the work. But since this is experimental how about you get bungs welded in both locations and in the open location simply find a pipe plug or use a dummy O2 or something. You first put the O2 in the proper place and see how the ECU behaves. If you're not satisfied then simply move the rear O2 behind the cat. And to extend the wires you should visit your local Nissan parts department with O2 sensor in hand. They usually have kits that the techs use to replace Nissan factory plugs. They might have both fittings you need. Then just get some 3 conductor 20 or 22 gauge wire and put it all together. You could even setup a switch inside the car and switch back and forth between front cat and rear cat O2s to get it all setup right.