Congrats to our New President Anguss!!
Remember to like us on Facebook!! - https://www.facebook.com/skylinesdownunder

Author Topic: Spark Plugs  (Read 1419 times)

westybob

  • RB26DETT
  • *****
  • Posts: 2990
    • View Profile
Spark Plugs
« on: July 05, 2013, 07:21:11 AM »
Well you can never stop learning. Like a lot of people I have been using and recommending BCPR7ES plugs for years but today Soichi told me to use PFR7 instead because the coppers (which he says are fine for n/a cars) misfire at high boost and revs - which rings true because the last time I had my car on the dyno at Torque performance he kept pulling the plugs out and gapping them down ( to 0.5 or so) as they were misfiring up top.

So PFR7s it is for me!

Pandaemonaeon

  • RB26DETT
  • *****
  • Posts: 969
    • View Profile
    • http://
Spark Plugs
« Reply #1 on: July 05, 2013, 08:35:50 AM »
I can't say that I have ever had a problem with coppers misfiring.
I started using NGK R5671A-8 and never had a single issue with them.
pure methamphatamachine

Team Sleeper

b00stinz

  • RB26DETT
  • *****
  • Posts: 5819
    • View Profile
Spark Plugs
« Reply #2 on: July 05, 2013, 09:13:35 AM »
Never had an issue with copper plugs misfiring like that. New plugs even solved a misfire. Perhaps when you start going to very high boost levels, but have been fine on my 20DETs and even 25DE+T.

gtsr

  • RB26DETT
  • *****
  • Posts: 9390
    • View Profile
    • http://
Spark Plugs
« Reply #3 on: July 05, 2013, 11:47:50 AM »
If gap the sparkplugs incorrectly you can damage the tips.

Missfiring at higher rpm is due to the ignition system being weak hence why you gap the sparkplugs down. If ignition sytem is stronger, can use stock gap. But by the time it starts missfiring, the cylinder where it missfired (coilpack) is probably already damaged (usually what happens).

westybob

  • RB26DETT
  • *****
  • Posts: 2990
    • View Profile
Spark Plugs
« Reply #4 on: July 05, 2013, 04:48:33 PM »
I have brand new OEM coil packs and for good measure sprayed them with an insulator " liquid tape". I put in a set of brand new BCPR7ES. Max boost is 1.5 bar and rev limit is 7000
The misfiring is not like a boost cut or faulty coil - it is almost inaudible but Torque Performance showed me the effect on the dyno screen. Soichi said that there was a very small amount detectable yesterday probably because of the brand new plugs. I want to eliminate it altogether.

I had been thinking of getting some of these:
http://www.aemelectronics.com/high-output-igbt-inductive-smart-coil-1240
but if a change of plugs will do it I'll try that first.
« Last Edit: July 05, 2013, 04:56:45 PM by westybob »

gtsr

  • RB26DETT
  • *****
  • Posts: 9390
    • View Profile
    • http://
Spark Plugs
« Reply #5 on: July 05, 2013, 07:28:50 PM »
Would think copper tips have a heat limit, so he's probably correct that it wouldn't work so well in turbocharged applications where heat levels are higher. Need to look at the heat limit differences between copper, iridium tips.

In saying that, have you double checked the heat range, as it's recommended to change heat range every 75-100hp.

What makes me think that is what NGK say here that a colder heat range is needed if engine is under heavy load, high rpm (racetrack use, etc) -
 
http://www.ngksparkplugs.com/tech_support/spark_plugs/p3.asp?mode=nml

A 7 with heat range seems to be a bit low (500hp+ engine???).

I noticed Shred has been playing with those AEM coilpacks on I think was a SR20DET (car was in NZPC magazine). Probably best to talk to them on how to set it up. But I think those coilpacks draw more power from stock electrical system.

If want a bit more from stock ignition system, HKS Twin Power would be best, as probably draws lower amount of power from electrical system, but is amplified on coilpack end -

http://www.hkseurope.com/electronics/twinpower.asp
« Last Edit: July 06, 2013, 02:53:21 AM by gtsr »

Pandaemonaeon

  • RB26DETT
  • *****
  • Posts: 969
    • View Profile
    • http://
Spark Plugs
« Reply #6 on: July 05, 2013, 08:32:35 PM »
Copper actually has the best thermal properties out of all the plugs available, so should handle it better than iridium or platinum.
I didn't open the AEM link, but I'm assuming it is their "smart" coils. If so I plan on running them too as the 17v input voltage interests me greatly
« Last Edit: July 05, 2013, 08:33:37 PM by Pandaemonaeon »
pure methamphatamachine

Team Sleeper

westybob

  • RB26DETT
  • *****
  • Posts: 2990
    • View Profile
Spark Plugs
« Reply #7 on: July 06, 2013, 08:38:04 AM »
The NGK application chart lists  BCPR5 for the RB25DE.

For the RB25DET it lists PFR5G so with 308AWKW (a tad over 400hp) I would say PFR7 is about right for me.

The coils sold by AEM are not made by them and are also available from NZEFI in Christchurch. If I had a bigger KW engine (say 350+) which was forged and balanced and revving to 8000 or more I would definitely be looking at a set.

Quote from: gtsr;617166
In saying that, have you double checked the heat range, as it's recommended to change heat range every 75-100hp.
 
A 7 with heat range seems to be a bit low (500hp+ engine???).

I noticed Shred has been playing with those AEM coilpacks on I think was a SR20DET (car was in NZPC magazine). Probably best to talk to them on how to set it up. But I think those coilpacks draw more power from stock electrical system.
« Last Edit: July 06, 2013, 08:39:17 AM by westybob »

gtsr

  • RB26DETT
  • *****
  • Posts: 9390
    • View Profile
    • http://
Spark Plugs
« Reply #8 on: July 06, 2013, 09:49:53 AM »
It depends on cylinder temps and that can change with A/F ratio, intake temps, etc. Probably best to read the sparkplug tips to know what is going on inside cylinders.

I know PFR5A is stock for R32 RB20DET (around 215hp) with -11 (1.1mm gap). Upgrade for mild intake, exhaust mods is PFR6A with 0.8mm gap and PFR7A if engine is very lean (it should be with intake, exhaust, FMIC, BOV mods).

I remember seeing PFR6A for stock RB26DETT, RB25DET.

westybob

  • RB26DETT
  • *****
  • Posts: 2990
    • View Profile
Spark Plugs
« Reply #9 on: July 06, 2013, 02:28:42 PM »
Quote from: gtsr;617176
It depends on cylinder temps and that can change with A/F ratio, intake temps, etc. Probably best to read the sparkplug tips to know what is going on inside cylinders.

I know PFR5A is stock for R32 RB20DET (around 215hp) with -11 (1.1mm gap). Upgrade for mild intake, exhaust mods is PFR6A with 0.8mm gap and PFR7A if engine is very lean (it should be with intake, exhaust, FMIC, BOV mods).

QUOTE]

Soichi doesn't tune lean. I am happy to take his advice on plugs but I am sure other people will have their own ideas - bit like engine oils!

gtsr

  • RB26DETT
  • *****
  • Posts: 9390
    • View Profile
    • http://
Spark Plugs
« Reply #10 on: July 06, 2013, 08:09:18 PM »
Quote from: westybob;617180
Soichi doesn't tune lean.


11's is lean, but not excessively lean.

Quote from: westybob;617180
I am happy to take his advice on plugs but I am sure other people will have their own ideas - bit like engine oils!

Fair enough. As long as it works, that's all that matters. :)

westybob

  • RB26DETT
  • *****
  • Posts: 2990
    • View Profile
Spark Plugs
« Reply #11 on: July 21, 2013, 12:11:05 PM »

blantant68

  • SDU Member
  • RB20E
  • *****
  • Posts: 29
    • View Profile
Spark Plugs
« Reply #12 on: September 04, 2013, 01:53:47 PM »
I put in some DCP7ES recently. They work great at my 10psi level. No radio interference despite being non resistor and no misfiring as they are regapped to .8m. Now to sort out my inconsistent 17yo coils....