scdroptop

iTrader: (1)

Thinking about changing spark plugs early on my 05 with 36k (I know, I know) basically I want the closest thing to a new car feeling with the crispest performance stock I can get before I do any intake/exhaust mods later.

My 2002 had plugs replaced last summer due to year, not mileage recommendation from someone here on CL and I just went with stock OE plugs and I felt an improvement in torque as well as saw better mpg.

Any proven HP gains with the iridium vs platinum and any other brands recommended over the stock OE ones? Please let me know if you have experience with anything other than OE and what the results are.

With some of my other performance cars, plug upgrades did make a difference. Thanks!

IS_250

iTrader: (2)

Last time I did plugs on my SC, I believe they came with Iridium from the factory.

scorpio74

I heard that the Iridium spark plugs are the best.

Bon

The OEM Denso plug was a SK20R11. A better choice is a Denso IK20.
The OEM NGK plug was a IFR6A11. A better choice is an NGK BKR6EIX-11.

Lexus/Toyota provided a plug that would last around 100,000 miles. This plug is a compromise between long life and fuel efficiency. The plug electrode is iridium and is 0.7mm in diameter. The better choice (IMO) has plug electrodes that are 0.4mm in diameter. Why? More power, better efficiency and better mileage. The down side? The plug doesn't last as long; perhaps 40,000 miles.

Why? The smaller the tip the better the spark. The sharper the edges of the electrodes the better the spark. For size and durability Iridium wins. The 0.4mm tip is smaller and works better, but because it is small it wears down faster.

The 0.7mm OEM plugs allowed the manufacturer to compete with other manufacturers saying you don't need a tuneup for 100,000 miles.

These Denso links provide some additional info:

http://www.globaldenso.com/en/produc.../features.html

http://www.globaldenso.com/en/produc.../features.html

http://www.globaldenso.com/cgi-bin/g...&action=search

I use the Denso IK20's and am satisfied. You can find them on eBay in 8-cylinder quantities.

I began using them when my '01 LS mileage began to decline. The new plugs put me back to at least where I began and I again can eek out 27-28-29 mpg hwy with a light foot and no cruise control. My mileage had slipped from there down to about 21-23 mpg max. I had around 70K miles on the original 0.7mm OEM plugs.

omair

NGK IX = great performance for any toyota non GE head

CAMAracer

iTrader: (1)

You might want to give Pulstar a try, seems to be working fine for me (thread search will result in some info).

Bon

I would hope that none our members will buy into this. 13mpg on a test car with JUST the addition of a spark plug; lies and rubbish. If the technology was available to do this, it wouldn't be just one company doing it. Auto manufacturers spend million$ to get any advantage they can with fuel mileage. Magnets in your fuel line and other strap-on gimmicks are similar ploys to separate fools from their money. To sum it up "bad science". $25/plug?? Just try to find an independent confirmation of the performance of these plugs. Better mileage? If you replace worn out plugs with new, of any kind, you will experience that. More power? Nothing is more unreliable than a butt-dyno. Real, complete, back-to-back, same conditions dyno results? Wouldn't every racer be using them, and I mean every racer because to a racer $200 for plugs would likely be the cheapest investment they could make to gain 1% performance by any measure. IMHO.

Good news, I guess, is that sparkplugs.com has them for 12.95 each. So if you want to experiment you can do it for a whole lot less now!

Yes

^^^^spark plugs use a lot of gimmicks to sale their product. there's no such thing as a "better" spark. there's either a spark, or there isn't one. if you're not getting a spark, you're misfiring, so you're losing power and gas milage. most plugs will give you near 100% reliability. after that, any performance gains are in your head.

scdroptop

iTrader: (1)

And this is why I love CL...opinions, experience...great knowledge and advice! You all are great. I think I am going to try the .4mm Denso and see if there is any difference.

One time a very wise rx-7 master tech who rebuilt thousands of rotaries told me that most of the time people spend all their money and time upgrading or modding their cars for performance when they started in the negative on their OEM setup---i.e., plugs, brakes, etc. He said, "get your car starting, accelerating, stopping and handling the best you can to OEM specs" THEN do your mods. In essence what he was telling me was that my stupid strut tower brace bar I was DYING to install I should pass on because my plugs and filters were nasty and I needed new pads! lol

mrblister

There is a new type of spark plug that is being made for underground racers. Its a 24 kt gold electrode that makes the best electrical contact out there . They cost $ 800.00 a piece and thats not bad considering gold is $ 1150.00 per oz . The only down size is they only last for about one mile before they burn up and your engine swallows the gold up. what a deal . I was going to trade for a set from a guy who had them I was trading 3 magic beans for them .

Jack

scdroptop

iTrader: (1)

See if you can throw in a bottle of "fountain of youth" and a can of "snake oil" and it would be a hell of a deal!!! lol

redliner8

iTrader: (1)

SCDropTop, any update on what you bought and your reaction? I'm going to be buying new spark plugs very soon. Thanks!

mandyfig

I, too have to do my spark plugs. This should be a very simple DIY, correct?

Just a matter of what to get for the plugs. I would not mind using the same spec plugs as the OEM.

mandyfig

scdroptop, if you wait, I will do a DIY on this. Let's just figure out what to replace the plugs with.

Pnuge88

iTrader: (1)

OEM is made for the car. works best with the car. upgrading/downgrading to the .04mm i can only imagine how much gas mileage and performance you will gain/notice :P