Hmm... that's pretty steep, IMO... but whatever... they're on, that's what matters.

I think some smoke/odor is common with most new exhaust parts....

 

It sounds much more ricey IN the car. have a friend drive your car while you drive behind him so you can really hear how it sounds.

 

I shall have to do that But I dont trust any of my friends with my car... Lol

Puppet - The somebtch pulls hard. Real hard. The headers are

Im going to see if I can arrange some Dyno time soon

 

01 cali-specs do not have that function, ours are more similar to the 02+

 

Test pipe- especially a non-resonated one will make your exhaust sound louder and raspier. I switched from my busted Custom Maxima test pipe (which was resonated) to Warpspeeds (which is not resonated) and sound levels greatly increased and got really raspy with Greddy EVO1 and HS headers on my 01 Maxima. I think I blew all the baffling or sound absorbing material out of the EVO1 cause it was quiet and got louder and louder as days went by.

I have a Mossy exhaust system on my Max (same as Cattman, same company makes both) and it sounds awesome, doesn't rust and fits great. Tone of the exhaust is very tolerable and only gives out sounds when U push the engine hard. Its deep, and sounds like it means bussiness- puts 350Zs and G35 exhaust notes to shame. I love my HS header/Warpspeed testpipe/Mossy exhaust.

 

I want in on these headers... Anybody have some money I can borrow and never pay back??

 

01 Cali specs have a set of butterflies in the lower intake manifold that closes off durring deceleration causing increased reversion of exhaust gases. If you look down by the V - between the cylinder heads next to the timing chain cover, you will see a dashpot/diaphram down in the valley which opens and closes these little butterflies. When shifting below 3K RPMs in a 5spd 01 Max, you will notice that the RPMs kinda bump up 200RPMs and then fall- it happens as soon as U depress the clutch. Its not noticable by most people, if you have a light weight flywheel it should go up about 300RPM-400RPM depending on the speed of the engine. Past 3200RPM this function is disabled by the ECU. ECU gives the injectors a extra squirt of fuel when you depress the clutch and let off the gas, EGR effect is created by closed butterfiles in the lower intake manifold and revision in the exhaust system.

 

You know, my hearing has been off the past week because I've had an awful cold.

 

Apparently I missed this. Did not know they were out yet, time to get busy.

 

You need wire extenders??? I have a '97 with a VQ35, same exhaust manifolds though, and the wires for the 02 sensors went in fine on the Budget Y pipe, I hope they go in ok with the new headers.

 

Just pushing out these mods eh Rich? Haha. I NEED to see/hear the new toys, we should meet up sometime...

 

Yes, I have an 03 Cali Spec

The problem is, the 02 sensors on the manifolds are Right at the top of the OEM manifolld. On Brian's new headers, the bung for the sensor is located at the 3-1 point of the manifold, which is right by the bend near where it joins the downpipe. Apparently this is for a better comparitive reading between the pre cat o2- sensor and the post cat sensor. Also, my Cattman catback needed an extender.

Let me tell you, I was AMAZED at how heavy the old **** was. The manifolds, the Pre cats (AMAZING!). Ugly old cast iron junk. My car has lost like 30 lbs!

I actually got a fed spec Cattback by accident, and I need to either drill a hole for the 02 bung or just get an 02 Simulator. I have a 02 sensor sitting in my house at the moment, and surprisingly Im not pulling a code.

*shrugs*

Just lucky!

 

Shure man! Anytime you want to! We'll set up a time and Nilesh can come see if his stereo is louder than my car at WOT

 

All 02-03s are Cali spec.

What "extender" does your catback need?

I don't think that there are Cali or Fed spec cat-backs.... they are all the same, aren't they?

When you say drill a hole for the O2 bung in the catback, I think you are referring to the downstream O2 sensors that would either have to be extended and bunged after the main cat or alternatively left dangling with an O2 simulator wired in. Either method is pretty standard with header installs on these cars.

 

Ok so then my question is. I have a FED SPEC '97 with a VQ35 essentially the exhaust manifolds are the same as on any 3.0 Motor FED SPEC, cali spec I'm not to sure about. The original o2 sensors that were on the original 3.0 motor with the budget y pipe went on fine with the VQ35, no extension of wiring needed. So since my car is a fed spec will the O2 sensors go on fine without the need of wire extenders?

 

Spot on

The pipe only had one bung for the downstream 02 sensor. Im going to purchase a simulator for the other one.

 

Cali-specs have to move two o2 sensors behind the main cat, while the fed specs only need to relocate one. The difference in hte exhaust is in the B-pipe only. If you recieved a fed-spec B-pipe you will need to have a second o2 sensor bung welded on. You can get this done for around $50 or so if you look around.

 

Wait what???????????? I'm so lost dude.

The headers contain 2 manifolds, and the y pipe. Why would I touch anything AFTER the cat. convertor??? There's only 2 O2 sensors that would go on the y pipe, or the headers themselves right?

 

Why would they make an EGR pipe on the headers if 3.5s don't have one. They made it FOR the 3.5.

 

wait the new gen2 headers are specifically designed for the 3.5L? I know the gen1 headers were a 3.0L design...and sr20den pioneered the gen1s and found out it fits the 3.5 without any modifications

 

because if you put on an EGR tube you can market the headers for both 3.0 & 3.5's.... all a 3.5 will have to do is plug the EGR and Cattman more than doubled its market.

Makes sense to me...

 

Well, here is the real deal.

There are two different part numbers for the headers. One for the VG30DE and one for the VQ35DE. The one for the VQ35DE does not have the EGR pipe.

 

I'll try to explain this, but those who know better, please let me know if I'm right or wrong here.

On a stock Cali spec, 2 sensors (front) are before the pre-cats and 2 are after (rear), this allows measurements of the difference in the exhaust gases before and after the precats. With headers, there are still bungs for the front sensors on the manifolds, but you're eliminating the pre-cats (so there are no bungs for the downstream/rear sensors), so in order not to throw a CEL, ya need to extend the rear O2 sensors after the cat, so the ECU thinks that the pre-cats are still there or still "working".

An alternative is to wire an O2 simulator in to trick the ECU (and leave the rear O2 sensors tied up and dangling somewhere), thus doing away with the need to extend the wires back past the cat.

If you're gonna be messing with all this, get to know this diagram well:

 

I did 1 wire extender for my first downflow 02 sensor. Didnt have the bung in the b-pipe for my 2nd one so I decided to get an 02 simulator and save me some time.

I am dying for it to stop effin' raining in Jersey so I can really test out the car. If I nail the throttle in 3rd at around 45, I can still get the tires to break loose in the wet

A question to all : There seems to be some sort of gurgling/popping/rattling sound coming from the exhaust, but only when I round sharpish corners at med-low speed. Is this a noise that is more prominent because the pre-cats are not there or am I running too rich? Might be a regular sound with headers, just not sure atm. k

 

What kind of sound is it? Does it sound like something banging against something? If so, you might need to add aftermarket exhaust hangers so the piping won't bang against the two cross members....If thats not your case, then it is very normal to "gurgle" after adding full exhaust...I'm running catless 2.5" piping all the way to the muffler...and the vq35 loves to let off a mean POP when the throttle is let off...

 

BTW, which store sells the 02 sims? I havent had any luck in any of the online stores I have checked.

 

www.o2sim.com

i bought a dual output version to simulate both downstream sensors...works great!

 

Hmm... It is possible. It might be banging, but it sounds like it is coming from the area of the downpipe/ cat. because it only occurs when turning. Where can you get these hangers from? And do I need to take off the exhaust to install them.

 

Hmm, now heres a thought. Is the ECU smart enough to recognise differences beetween sensors? because the Sim sensor reading will be different to the sensor I actually have sitting in my b-pipe

 

I recommend wiring both o2 sims to both downstream o2 sensors...u can still have your o2 sensor plugged into the bpipe becuz the simulator taps into the wires before the connectors....

I noticed you only have one o2 plugged into the bpipe becuz you didn't have the other bung welded one....where is this o2 sensor hanging at right now?

The ECU won't be smart enough to set off a SES light...I've had both sensors simulated for quite sometime now and no SES....as with many other members on this forum

 

The first cross member is located where the cat meets the bpipe...I had this problem when I installed my headers and my piping would bang against the cross member almost all the time during daily....

Another alternative is to add hose clamps around the exhaust hangers to raise the piping a few MMs...this is what I did becuz I was too lazy to buy aftermarket hangers and taking off my exhaust...plus the hose clamps cost like $3 wheres aftermarket mounts cost alot more than that...

 

Okay, My 2nd 02 sensor is sitting in my loungeroom at the moment
I just ordered the sim from the website. I will connect the sim to the sensor and leave it in my engine bay instead of running another wire extender.

Adding the hose clamps sounds like the way to go, but how do you go about doing this. Do you think I could pull it off with my ramps? Or will I need to put the car on a lift?
Steve, from the way you have described it I am pretty sure its the 1st crossmember that is causing the issue.

 

Puppet, you're absolutely right about the cali-spec 2k's. The fed-specs have only one 02 sensor after the pre-cats, therefore you only have to move one sensor. If you have cali-spec you should really get a dual channel o2 sim and use the o2 sensor to just plug the hole.

 

Aren't there two ports on the Cattman B-pipe for the sensors?

 

You should know better than most of us, since ya have one, but RBrown here says there's only one. Check yours to confirm. I have a Frankencar b-pipe and I have no O2 bungs on it.

 

Mine only came with one. Strange.

 

does relocating the o2 sensors apply when installing just a cali spec Cattman y pipe???

 

I will be installing these on a 2k0 5 speed in a few weeks. I am glad they managed to get more power out of these but I really wish the primaries were longer. So much for long tubes.

 

I Have two holes in my cattman bpipe...originally had one cuz this is a Fed-spec bpipe...they aren't being used by o2 sensors becuz i am running the simulators...so currently they are being plugged up...you can ask cattman to add extra holes to your bpipe...thats what I did and he only charged me a few bucks...

 

Let us know how things go...are you going to post up sound clips?