Are "high performance" spark plugs worth the investment?

[the desolate one]

I was pondering buying some high performance spark plugs to give my 87 Camry a little more punch on the road. I've heard conflicting reports about the efficacy of them. Some people say that not only do high performance spark plugs give you more power, but they also give you better gas mileage. I've heard other people say that a set of new 69 cent spark plugs is gonna give you the same performance as high performance, and that plugs that are labeled as being "high performance" is nothing but a gimmick to get people to pay more money on spark plugs. Some people say that high performance spark plugs are MOST effective on older cars, like my 87 Camry, as older engines benefit most from the extra performance. I would like to hear all of your opinions on the issue, and also, if you recommend high performance plugs, which ones would you recommend for an 87 Camry? Any info on the matter would be greatly appreciated!

[auto_robotics]

I use the NGK Iridium IX's on my 3SFE. I like them, but I can't say with any certainty that they add power. I think the difference would be small enough you'd have to dyno the car to see.

My understanding is that the coatings such as platinum or iridium do more to extend spark plug life than improve power. They help limit erosion of the metal conductors over time.

[white90dx]

Standard copper spark plugs (NGK, not Bosch!) really are the best for performance. Platinum and iridium spark plugs are for 'good enough' performance while increasing longevity (nice for people who pay to have work done on their cars or have hard to access spark plugs). A standard copper plug should be changed every 10k-15k miles while the platinums go ~60k miles and the Iridiums up to 100k miles.

Well, at least that's the simplified version...

-Charlie

[Tom 2000]

Agree with Charlie.

It's about physics. Copper is an excellent electrical conductor (Silver is little better, but not very practical for a spark plug). The other rare-earth type metals - such as platinum and iridium are not as good conductors, but are extremely durable, hence the extended spark plug change intervals....

I've used various kinds of plugs - NGK, Denso, Champion, Autolite, Bosch, etc... over the years. What I found is that the OEM specified plugs - NGK or Denso really are the best. Both from cost and performance.

Stick with copper plugs (NGK/Denso) on your 87 Camry. They are cheap, give the best performance. Also, changing the spark plugs on a 3S-FE is a piece of cake!

[MR2Jedi]

Ditto the 2 above. Copper is the best conductor and delivers the strongest spark. Iridium and platinum are mainly for longevity, as copper plugs only last up to about 4K miles.
As far as perfomance, copper is the way to go.

[white90dx]

Originally Posted by MR2Jedi

Ditto the 2 above. Copper is the best conductor and delivers the strongest spark. Iridium and platinum are mainly for longevity, as copper plugs only last up to about 4K miles.
As far as perfomance, copper is the way to go.

The only thing I'd note here - on the 3s-gte, the 5k mile copper spark plug change interval is good (as is a 15k mile wires/cap/rotor change). On the 3s-fe and other non-performance motors, 15k miles on copper plugs is fine with 60k for the other components.

-Charlie

PS. When I was running coppers in my WRX, I changed them at 15k miles, but I run NGK iridiums now as the spark plug changes are more difficult (and the car was tuned with those plugs).

[nogard]

I like NGK V-Power plugs, cheap, and easy to change on a 3S-FE. Get yourself a piece of hose that fits over the plug to help with install/removal, and use a little anti-sieze on the threads of the plug. I usually only get about 12K miles, a little over a year on a set. Distributor rotor is cheap and easy to replace, check that too. And if the cap and wires haven't been changed in a while check them too. I would recommend buying OEM, or Carquest, you get what you pay for.

As far as performance, think of it this way, by making sure you have good (new) parts installed will bring the performance back up from less than stock to stock. Not that you will get more than stock performance, but are possibly increasing performance relative to what you had prior to tune-up.

[Nut Behind The Wheel]

In my opinion, the answer to your question is yes, definitely, if you switch to NGK Iridium IX plugs.

In every car I've switched to them in, there has been a dramatic improvement in idle quality and smoother engine operation overall. They are the only spark plug I have ever seen that can do this.

From what I've heard, this improvement in combustion is due to the very fine, almost needle point of the center electrode being so small that it exposes more of the spark kernel to the surrounding air/fuel mixture, providing for a quicker ignition of the A/F mixture.

I used them in my '90 V6 Camry, and the slightly rough idle became completely smooth. Same for the '72 Honda Z600, with a 600cc twin cylinder air cooled engine, and same for a highly modified '65 Mustang with a 347 stroker kit pumping out 395 RWHP @6000 rpm. Also used them in a '96 5.8L F-250 Ford pickup truck, and a '76 400 CID Ford LTD, with the same results; much smoother idle, better off idle "tip in" throttle response, and smoother engine operation overall.

Can't say for sure if there's more power because of the Iridium IX's, but because of the dramatic improvement in engine smoothness, I'm hooked on them for that reason only.

They are not available for many engines, so if they are for yours, I would encourage you to give them a try. At around $8.00 to $10.00 each, and lasting for a minimum of 30,000 miles, they won't greatly affect the overall lifetime operating cost of your vehicle!