Sparkplugs

[D1Champ]

I was wondering if there is any significant benefit in choosing performance plugs for the Sr20DET. OEM works but are platinum or iridium plugs that much "better". What are the real gains of upgrading to these types of plugs. This is a daily driven/weekend drifter setup.

[9240sx]

Platinum and Iridium last longer,And sould make a bigger spark,But Doesnt the Sr come with NGK Platinum plugs stock?My motor had them,and my FSM says to use only platinum tip plugs. PFR6B-9

[Hijacker]

i believe NGK coppers came stock on the car. The benefit from plats and iridiums is a more precise spark.

[compression]

I ran iridiums for a while. I didnt like them because they fouled too easily and then I have misfiring. I switched to the cheap-o copper ones (BKR6E) and have been much happier with them.Since I am usign a standalone EMS, the engine sometimes runs very rich, which would foul the iridiums. For a stock ECU, you probably wont have this problem, so iridiums would possible work better. But I see no point in running them. If they do last longer, then that may be a reason to use them.THis is not really relevant to this post, but....Heres a post from the sr20forum.com by a user named "BigToe". He has a lot of very insightful posts:__________________________________________________________The plug gap is based on the dynamic cylinder pressure and the current capacity of the coil/ignition circuit.The larger the gap the more current required to bridge the gap.The higher the dynamic cylinder pressure the more current required to bridge the gap.High boost or high CR will generally warrant a smaller gap if the OEM ignition is marginal in terms of current capacity.

No electrical circuit will generate more "power" than is just enough to get the job done.A 100hp motor only makes 100hp and draws full running amps when the load is sufficient to warant it. So does the ignition circuit. It only EVER draws as much power as is needed.If the plug is fouling, cold or hot, it's usually carbon tracking across the inner electrode via the ceramic insulator (carbon conducts electricity) to ground. In this instance the higher the spark energy the more the plug fouls up as the arc seeks the past of least resistance, ALWAYS.

High Voltage coil marketing is a ploy on ignorrance to sell the ultimate "Hot Coil".

The challenge is dwell time on the primary winding of the coil more so as average rpm has increased on the moder car. This is the only reason we have wasted spark and coil on plug systems, it's to gain dwell time by splitting up the duty cycle on more than one coil.Old American V8 iron is where all this came from, V-Plug, Splitfire, Multi Spark etc, it's all because flame propagation in the heads is/was poor and all sorts of tricks were used to compensate for bad design. Just think of the real reason the Hemi was so impressive, it's combustion chamber was better and flame propagation was better.Finally, if you run wasted spark, or know someone who does do the following;

Remove all the plugs from the head, keep them on the leads.Ground only one plug so it can fire.Crank the motor and look at how tiny and weak the spark is.Ground the next plug fed by the same coil and try again.Big, BLUE, spark on both plugs.Reason: The Wasted Spark circuit requires that the circuit be terminated back to the coil. It must go through Gap#1 in the correct polarity, then Gap#2 in REVERSE polarity.

That being said, the point is, here are your 500, billion, 3 gazillion volts firing two plugs out of phase (one cylinder is always in polarity, the other is always in reverse).

But Mr Coil Seller is telling you you need 600 billion, 4 gazillion volts just to fire one plug.

The other thing is that the highest current draw is just prior to the gap being bridged, thereafter the air between the gap is ionized and therefore conducts electricity, so the required current drops until it gets to zero as the secondary coil winding voltage goes to zero.

Plug gap does not give more power and bigger bang and higher temperature.