I read a thread on this forum that you should never, never, NEVER! run Platinum plugs under boost. Does any one have Platinum plugs on your turbo car?? Why is this a bad thing?
Never run Platinum plugs under boost?? Why?
- Thread starter Koenigturbo
- Start date
I think 'someone' has been exaggerating just a bit, as the turbo Supras *come* with platinum plugs. I ran mine for years without problems, but I've recently switched to coppers to save a few bucks. They need to be changed more often, but they are a fraction of the price.
Agreed...you can run platinum plugs with no problem. IMO, NGK coppers are better, but you'll have to change them more often.
I think the only reason most OEM applications call for platinum plugs is because that way, the dealer doesn't need to change them at all service intervals and only change them around the 100k mark.
In all my imports, and to all my customers I always just recommend the NGK V powers, they are a wonderful plug that arn't 11 dollars a piece..
In all my imports, and to all my customers I always just recommend the NGK V powers, they are a wonderful plug that arn't 11 dollars a piece..
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Platinum isnt usually the best choice in plug for a boosted application.
Sure the car came stock with plat. plugs. The manual also calls for 87 octane fuel. Do you run 87 in your car and drive it at the stock boost level with all the stock components on it? Most of us dont. Generally the rule of thumb has been to always run copper or iridium plugs in a high performance boosted application. And they're cheaper.
Check out the turbo Honda world. Just about everyone run's NGK 6097 coppers on their turbo cars.
Sure the car came stock with plat. plugs. The manual also calls for 87 octane fuel. Do you run 87 in your car and drive it at the stock boost level with all the stock components on it? Most of us dont. Generally the rule of thumb has been to always run copper or iridium plugs in a high performance boosted application. And they're cheaper.
Check out the turbo Honda world. Just about everyone run's NGK 6097 coppers on their turbo cars.
There's nothing intrinsically wrong with running platinum plugs...they will provide good service even in boosted applications. Platinum plugs are not as efficient as copper, but the harder platinum will resist erosion much better. Using the correct heat range and properly gapped, platinum plugs will work fine. High performance (turbo) motors will usually need a colder plug and the gap reduced. What you are looking for is to keep the tip between 500 and 850 deg C...this heat range will cause the plug to "self clean". Very important in preventing a misfire.
Where the coppers are superior is their thermal/electrical conductivity...copper has the ability to dissipate the heat from firing better from the tip and the only metal that's better at conducting electricity is silver. It's an excellent material to produce a strong spark and keep hot enough to prevent carbon build-up (fouling). It's downside is it's soft and subject to more rapid erosion...that's where the use of more exotic metals came from in order to extend spark plug life.
The advantage of iridium plugs are better heat conductivity and lower resistance than platinum, but the metal is more expensive. This allows for a tip that's 25-30% finer than what you see on platinum plugs. The use of iridium allows this, it's a harder metal compared to platinum. This fine tip does have a drawback, at high RPM (heat load) the very fine tip on an iridium plug can "glow plug" causing pre-ignition or a misfire.
Keep something in mind...platinum and iridium are in the same family of metals on the Periodic Table
The explanation RedEj8 posted is basically a bunch of rubbish...it's based on the usual innuendo you see on a lot of forums. Basically "I do it, so it must be best". There are advantages (and disadvantages) to each plug, but it's not for the reasons he stated
Where the coppers are superior is their thermal/electrical conductivity...copper has the ability to dissipate the heat from firing better from the tip and the only metal that's better at conducting electricity is silver. It's an excellent material to produce a strong spark and keep hot enough to prevent carbon build-up (fouling). It's downside is it's soft and subject to more rapid erosion...that's where the use of more exotic metals came from in order to extend spark plug life.
The advantage of iridium plugs are better heat conductivity and lower resistance than platinum, but the metal is more expensive. This allows for a tip that's 25-30% finer than what you see on platinum plugs. The use of iridium allows this, it's a harder metal compared to platinum. This fine tip does have a drawback, at high RPM (heat load) the very fine tip on an iridium plug can "glow plug" causing pre-ignition or a misfire.
Keep something in mind...platinum and iridium are in the same family of metals on the Periodic Table
The explanation RedEj8 posted is basically a bunch of rubbish...it's based on the usual innuendo you see on a lot of forums. Basically "I do it, so it must be best". There are advantages (and disadvantages) to each plug, but it's not for the reasons he stated
+1 to anyone that said run copper. they are cheaper they work great they they are easier to tune with.
you are right about the dealers using platinum to save on warranty costs.
you are right about the dealers using platinum to save on warranty costs.
"I heard" should have set off warning bells Koenig
Personally I had issues in the past when I was running LPG during sustained top end runs of the IR plugs "glow plugging" and causing a misfire, this only happed after the run to 140+ mph and holding it there with sligtly lean mixture.
I fitted NGK Copper's same gap same heat range and it was cured.
Personally I had issues in the past when I was running LPG during sustained top end runs of the IR plugs "glow plugging" and causing a misfire, this only happed after the run to 140+ mph and holding it there with sligtly lean mixture.
I fitted NGK Copper's same gap same heat range and it was cured.
gtsfirefighter
SM Expert on White trash
i had IK24's in my car and had a horrible top end misfire, almost like a rev limiter. i switched them to Denso 2330's and the car is way better. i thought the iridiums were supposed to be super durable and long lasting. mine had about 10k on them and the center electrode was like new... however the side/ground electrodes had large divots eroded away... apparently its only single sided. if both points were iridium, the plugs would be great... but to run the 2330's, you do have to change them frequently. my friends and myself all like to time the plug change intervales w/ the oil changes: 5000 miles.