I know there's a Megan Racing header for a scion tc that fits our 2.4L. Has anyone installed a header? I'm curious as to the issues we gotta deal with.... o2 sensors, cats, downpipe, fit issues, etc..... I want a header but I don't want to throw codes or fail emissions.... Is it possible???
Here's some more info than what I had PM'd you (just so everyone else can chime in or get the info) :
1.) It will fit, but its a little tight and I would use the gasket that comes with the header
2.) Since the pre-cat was in the OE manifold you will pop a p0420
a.) Can fix with a spark plug fouler mod, but it blows not recommended at all
b.) You can get an 02 sim which will fix the problem, but its pretty shady legally
c.) You can extend the 02 harness and install another cat welding in a bung after it
3.) Down pipe would be for a turbo install (post Turbo)
4.) If your thinking of a mid pipe I didn't look into it, but our exhaust config is a little off from the TC or XB so you might not have very good luck.
If you are worried about emission there are 2 kinds of testing OBD-II reading to check that you have no codes even ones that won't always pop a CEL. And then there'e the dreaded sniffer that will actually measure your exhaust gas output levels. I didn't have emissions testing in my area so I didn't really care, but if you do I wouldn't really worry about a header unless your prepared to get it sniffed and then see if you need to get another CAT etc. If you do go with a header and you have to get smoged make sure you run it like a bat outa hell (no chip/tune/etc. stock ECU strategy) for a few miles to get the remaining post cat heated up. That may allow you to pass your emissions depending on the state requirement.
Well I just briefly read through the Illinois emissions site and they are going to a OBD test only. Got rid of the old "sniffer". So looks like the sim would be the way to go... Which sensor did you install the sim on? The upper(closest to head) or the lower? What pipe did you use between the header and cat-back system?
Digglesworth wrote:Well I just briefly read through the Illinois emissions site and they are going to a OBD test only. Got rid of the old "sniffer". So looks like the sim would be the way to go... Which sensor did you install the sim on? The upper(closest to head) or the lower? What pipe did you use between the header and cat-back system?
For future readers: The first O2 sensor monitors how the engine is running and comes before the cats. The second one checks catalytic efficiency and throws P0420 when efficiency drops below 85%. The second one is a simple O2 sensor that can actually be spoofed with a resistor and capacitor.
Remember that you can overheat the resistor and capacitor until they no longer function, and of course this is all illegal unless you're only doing offroad.
"If you don't love me at my diddliest, you don't deserve me at my doodliest." - User ktluvscricket of reddit
TireToast wrote: ↑Mon Mar 04, 2019 12:15 pm
How significant of an effect do you think the Megan Racing headers would have. Especially if I intend to have the ECU tunned?
Probably minimal. I don't think there is anyone that can tune an ECU on the 09+?
TireToast wrote: ↑Mon Mar 04, 2019 12:15 pm
How significant of an effect do you think the Megan Racing headers would have. Especially if I intend to have the ECU tunned?
Probably minimal. I don't think there is anyone that can tune an ECU on the 09+?