65 replies to this topic

[markiitourerv]

Got some new spark plugs yesterday.
Everbody wanted $15 a plug for platinum or iridium.
Genuine Denso platinums ended up costing $10 a plug from dealer.
Toyota listing was wrong in comparison to Denso site which recommended
PK20TR11.
So I got them instead.


All dealers will have these in stock as they are the same as fitted to some camrys.

Bargain.

[KPCresta]

Your best bet is to for NGK coppers, thats what the Soarer boys use

the code I think is : NGK BKR6EC

gap them down to 0.8mm and change every 7000kms....

they are about $4 each?

[markII streeter]

I use irridium plugs in mine, I think the whole set of 6 was 80 bux or so

[ghost]

KPCresta, on Apr 8 2006, 11:27 AM, said:

Your best bet is to for NGK coppers, thats what the Soarer boys use

the code I think is : NGK BKR6EC

gap them down to 0.8mm and change every 7000kms....

they are about $4 each?

.. for a relatively stock engine.
I believe the word is to go for a colder plug and a smaller gap when running an aftermarket turbo and/or more boost. ie. BKR7E with a 0.7mm gap (or less)
I am currently having problems with ignition retarding from misfires that may possibly be related to the plugs. I will change the plugs soon to see if this rectifies the issue.

[Trav]

Hi, I thought I might just add that today I replaced my plugs (they were denso iridiums with a 1.1mm gap) with NGK BKR6ES (copper standard) that i gapped down to 0.8mm as mentioned in the posts above. Doing this seems to have solved the nasty misfire problem I had - not bad for $24! I had previously inspected the coils and cleaned the area thoroughly with no change.

The ignition system must be pretty weak, so a little build up in the iridium electrode must suck up the voltage?

[Hayai]

misfiring also occurs due to higher boost, which blows out the spark before it ignites , u'll have to excuse my reference as i'm a nissan boy from way back but RB20's a notorious for mis-firing when boost is turned up even the slightest. Closing the gap means the spark will be smaller but more intense. therefore making it harder to blow out. of course going the copper plus alone without regapping can also solve the problem as copper is a better conductor of electricity. And if u have copper plugs and regap them and it still misses .... then u'll have to start looking at other more expensive parts to replace.

[CD1J]

Yes like gold anode plugs as it is the best conductor though I would hate to think of the price if they did infact make them =/

[TRD JZX100]

One thing no one has mentioned yet in this thread, so if you didn't know already, NEVER regap Iridiums. NEVER. YOu may damage the electrode and then your nice expensive plug is useless.

Also on the topic of gapping. What you actually want is the largest gap possible that will not cause you issues. It is no use going from a 1.1 gap down to 0.8 or .0.6 because those gaps may be too small for your application. yes, they will stop the misfire but they will also stop your engine ignition system from performing to it's optimum.

Going to a colder plug (possibly with smaller gap) will usualy remedy misfires in high boost applications but will also mean that the plugs will foul quicker in normal driving conditions too.

So it's a matter of horses for courses IMHO. You just have to find the best solution for your particular application and driving style.

AS for platinum, iridium or copper plugs. I find the coppers work best on modified cars, plus I'd prefer to change my cheap copper plugs ever 5,000Ks rather than trying to rely on my expensive iridium/platinum plugs to last...

These are just my observations so nothing is gospel... take it or leave it.

[FRpilot]

ive never realised that

its weird coz my mates have been regapping their iridiums with no problems

[TRD JZX100]

More spark plug related info can be found here: http://lextreme.com/sparkplug.html