I installed my plugs yesterday and now I have such a smooth idle. Dam denso plugs were allowing my exhaust to pop after every rev I made. That meant that not all of the gas was being burned, so I took the plunge and ordered them. Heres the pic of my old Denso Plug and my new NGK Iridium plug. The drivabilty is so much better and the gas milage went back up!

 

im using ngk iridium ix in my civic si....very good plugs

 

I am going to vegas i an hour, so I will see if the gas milage is back to normal. :D

 

Various Toyotas come with various plugs. There are conventional, dual-electrode conventional, platinum, dual electrode platinum and irridium. The conventional plugs last for 30K with practically no change in performance. The platinum plugs go 60k, and the irridium go 110k. Each engine uses a particular plug for that application and you can bet your ___ that Toyota knew what they were doing when they installed plugs in your car. Lit is lit and thats all plugs do. Period. The cars ECM has a sophisticated Misfire Monitor system that will detect and record a single misfire through measuring crankshaft accelleration at each firing pulse to detect misfire. If your car was misfiring the MIL (check engine light) would light and if it was a dead miss the light would flash to warn of impending converter damage.It would set a code to tell which cylinder was misfiring or set a "random cylinder misfire" code if they were all misfiring. As far as not burning all the fuel or such, again the O2 sensors would register this and if fuel trim varied by 15% or so the MIL would light and record a code for "fuel trim rich" or "fuel trim lean". Irridium plugs are fine for the engines that were designed to use them and a waste of money for those that were not. The only performance gain they could possibly give over the stock plug is by increasing the power-to-weight ratio by lightening your wallet! ~~~~~~~~~~~~~scott

 

Is that really why???

FAWK, I have like 3-5 pops when I shift and even more when I race

 

Unburned gas pops in the exhaust. So if the plugs are fouled up, say hello to popping exhaust. :D

 

There would have to be sufficient oxygen present in the exhaust to burn any unburned fuel. One of the most common ways to introduce the extra oxygen is by an ill-designed exhaust system that allows reversion when you chop the throttle. Either the pipe is too big or the muffler doesn't have enough backpressure. Most exhaust systems designed for street use dont pop.

 

2.25" piping, dc headers, no cat, no resonator, free flow muffler.............HMMMMMMMMMMM

 

Thats funny because I was able to make my stock system pop before my exhaust system was installed too!!

 

ill tell you what... all I know is that I spent $20 a while back on a set for my 91 mr2 turbo and it saves me a lot of headache on replacing my copper set every-other oil change other than that, I really didnt feel a power difference at all from copper -> iridium

 

but you didn't put one in your scion, so you don't know if there is going to be the same rating.

 

Finally a voice of reason cries out in the wilderness

Save your money kids. New fancy plugs and bright yellow spark plug wires won't make the hamster run any faster in that wheel. You would think after years and millions of dollars of suckers money spent "souping" up Civics with faux mods like thie people would know.

"Hey man... I jus' got a new super ultra turbo battery from Costco, it makes the ignition stronger and gives you like 15 more horsepowers, man"

 

If you haven't done it yourself to a scion, than you really can't say to much. And comparing this car to a civic is not the right way to go. The toyota motor is a different design than the honda.

 

ok quick question. Are the Stock plugs in the xB Resistor or Platinum? I'm about ready to replace my plugs real soon.

 

i am pretty sure they are twin electrode platinum plugs. if you make the switch to a different kind of plug, you will notice a whopping 0.001% difference.

 

Yellow Sparkplug wires? Damn, where can I get some? better yet, where would I put them on my xB?

 

Sorry if I offended anyone, I didn't mean to be a d1ck.

But, I don't have to put special sparkplugs in a Scion to know that it will do nothing. It makes no difference if it's a Civic engine or not. Two small inline 4 cylinder engines that burn gasoline.

In facgt, You can compare it to any non-high performance car you want. V6 Camry? sure. Ford F150...whatever. Quad tip irridium turbo super-deluxe spark plugs aren't going to give you any meaningful increase in horsepower unless you are replacing fouled plugs with them. Neither is a more powerful battery or new spark plug wires.

I don't know everything, but I do know cars. Take my word on it.

See if you can find reputable dyno results showing a power increase from spark plugs on a Scion, or any other car remotely similar to it. Unless the laws of physics have changed since I last checked, it ain't gonna happen bro.

 

I bought my Irridiums at Autozone for like $12 a piece. I drive the ____ out of my xB and I'd have to say that it's a noticeable difference. I'm also running the Injen short ram intake and have a ground wire kit I made myself. I've put 12,000 miles on my car in the last 4 months and when I changed my plugs they looked pretty good but had a little carbon buildup. They are a well designed plug, but there are better.

I'm not sure why everyone on here thinks that Toyota makes a system that is so exact that by putting in different plugs you're going to ruin the way the ignition works. It would be like saying that you're suspension won't work better with better rims and tires. Because you know, Toyota designed it to work together. Sorry, when I put my light weight Konig Heliums on with Yokohama Parada SpecII tires the cornering capability went way up. Yes there is alot more road noise, but thats not a big deal to me. You put a better more capable plug in your motor and it will spark under harsher conditions. And it will be more likely to create a cleaner burn under normal conditions.

The factory ignition system may have a really great sensor network that can read all kinds of information and do wonderful things with it. But each combustion is completely unique, and the better the burn you get, the more power you will make. Don't act like combustion engines are any more technological than they are, you ignite distilled petroleum, it expands, you turn heat energy into motion.

The performance gain for the money you spend is your choice. I went with it, and I'm impressed so far.

 

Looks like I have to prove another person wrong like I did on the tC dual exhaust topic, why don't people listen to te exhaust guy that has scion knowledge. And I never said you had to change the laws of physics, just try out the plugs catch up to me!

 

I have a little Toyota and Scion experience myself and I'll be the first to wave the BS flag on a lot of this discussion. OBD II monitors misfire EVERY SINGLE FIRING CYCLE. It records it as misfire data. The A/F and O2 sensors record oxygen content of the exhaust gasses. If incomplete combustion occurred the long term fuel trim numbers would reflect this. The stock plugs for the most part work perfectly and I also can't comprehend some folks claims that so-and-so's plugs increase horsepower. I call bull____ and would be very interested in your sources for these incredulous claims. Anyone remember Splitfire spark plugs? Didn't they also make all these wonderful claims? Why not toss some Splitfires in your car?