Yea, and they are all the same thing... Megans.

 

I would be really interested in headers with or without the cats. If they didn't have cats, I would just install a couple cats further down stream and relocate the secondary O2 sensors.

I would hope that it would be equal length with decent collectors, but I realize that optimizing the design further than that takes lots of R&D.

 

There's also not much space in there.

I'm going to contact danielm from Mazzuri Super. He makes a set of headers for the IS300 that have had better results than other headers and for the price... they seem to be unbeatable.

His website is www.mazzurisuper.com

He's a member on www.my.is so you can contact him there as well. He has showed interest in making them for the IS350... if more people bug him about it, he may start working on them sooner.

 

You got Megan headers?

 

Holy cow those are nice too!!

 

They're pretty, but they have one (I consider) serious drawback. The O2 sensor bung is only sampling the #1 cylinder. As long as the rest of the engine is fueling the same as #1, you're OK. If it isn't, you could detonate any other cylinder to death and the ECM would only be able to use the knock sensor to avert disaster instead of adjusting fuel to properly compensate. It's a trade off. There's no convenient place to connect the OEM sensor so it can sample all cylinders without requiring a harness extension or a different O2 sensor when you buy the header.

 

He no longer includes an o2 simulator or hole to plug in the stock sensor. At least thats what I gathered from an update note he made on the page.

 

You can't run without a primary O2. The ECM will not work except in limp mode. There has to be a bung somewhere for it.

 

Please note, that this system no longer comes with an o2 sensor, because a few people where having problems with the o2sim.com sims we where using, and to be able to do an exchange you have to be the one who buys the sim. So because of that, we no longer include it with the system, but you can always buy one from http://www.o2sim.com.

 

Right. That's for the secondary O2, not the primary. You can't sim the primary, the ECM will have a fit and run like crap. The O2 sim just replaces the O2 sensor behind the cat so you don't set a DTC on an OBDII engine management system. Last time I looked at O2 sims, they were a dying breed. Is this site still active?

 

Ahh ok, I see what you are saying now.

 

I would be really surprised if that sim would work. The ECU's are getting so good at detecting them, and this just looks like a very basic 555 timer type. I tried one on my S2000, but it never worked. I had to get an ECG sim that actually had inputs other than just power (5 wires) with a simple microcontroller. I don't think they are available anymore though due to pressure from the EPA.

EDIT: Actually, I don't know if our secondaries are wideband or narrowband, so that would be another issue.

 

Secondaries are NB. For sure. Only the primary is a planar WB.

 

Does anyone in so cal have a set of megan headers they want to test? I have a dyno and an IS350 w/ out the manifolds in it right now .... or i guess we could build some NA headers for it while the manifolds are out given enough interest of course.

 

YES! Please make us some headers. There are plenty of people wanting more than just intakes and exhausts. Headers would be a really good next step, I believe.