11 replies to this topic

[caterham2]

My LJ XU 202, Ian Tate engine, 10.8 :1 comp, 3x 2" SU, about 245 HP runs happily on BP7ES plugs, with resistor leads, points ignition or Pertronix as currently fitted no issues even in heavy traffic.If you have good resistor leads you won't need resistor plugs, it's an "either /or situation"

[grumpy xu1]

I'd be running the resistor plug, simply because my wiring will be back to factory style. Gary.

[jd lj]

The resistor plugs are good if you have other electrical equipment. I use them to assist in logging rpm's on my AFR gauge.

[71xu1]

I use the resistor plugs no problems.

[RallyRed]

hmmm...learn something every day.

 

This thread made me do a read up on what the terms Hot Plug and Cold Plug actually means.

 

My LJ with blue 202,hi comp, 200rwhp, tripple Webers, Scorcher electronic ign.  etc has always had BP5ES plugs.  ( been running it like that for years)

 

Had someone a while back say that I should run colder plugs, never did that.

 

Looks like most people ARE running the Colder ones in this sort of application....for the cost of 6 plugs, reckon I will go from a 5, to a 6 version?

 

Thanks

Edited by RallyRed, 01 November 2018 - 07:42 AM.

[jd lj]

hmmm...learn something every day.
 
This thread made me do a read up on what the terms Hot Plug and Cold Plug actually means.
 
My LJ with blue 202,hi comp, 200rwhp, tripple Webers, Scorcher electronic ign.  etc has always had BP5ES plugs.  ( been running it like that for years)
 
Had someone a while back say that I should run colder plugs, never did that.
 
Looks like most people ARE running the Colder ones in this sort of application....for the cost of 6 plugs, reckon I will go from a 5, to a 6 version?
 
Thanks

If your plugs are showing the correct colour to be self cleaning then stay with the 5's. I'm currently running 6's but plan on changing to the 5's for a slightly hotter plug. Dcoe's prefer a slightly richer AFR to provide good tractability (average 12.5 AFR)so a slightly hotter plug may be better suited. But it's just trial and error until you find the plug with the heat range best suited to your particular set up.

[I'm a Red Motor fiend]

Col, google 'how to read a spark plug'. There are a few different signs to look for in regards to heat range, timing and mixture.
My comp is 11.6:1 and I run NGK BP6ES with 2" SU's and mine read well for my application.
What James has said above is spot on tho, 5's may be fine for your combo.

[RallyRed]

.

If your plugs are showing the correct colour to be self cleaning then stay with the 5's. I'm currently running 6's but plan on changing to the 5's for a slightly hotter plug. Dcoe's prefer a slightly richer AFR to provide good tractability (average 12.5 AFR)so a slightly hotter plug may be better suited. But it's just trial and error until you find the plug with the heat range best suited to your particular set up.

 

 

Col, google 'how to read a spark plug'. There are a few different signs to look for in regards to heat range, timing and mixture.
My comp is 11.6:1 and I run NGK BP6ES with 2" SU's and mine read well for my application.
What James has said above is spot on tho, 5's may be fine for your combo.

Posted Today, 12:01 PM

Thanks gents, there cannot be too much wrong with the current ones, they have a nice colour to them, but i've never done a real plug chop to see.

Thanks again.

Edited by RallyRed, 01 November 2018 - 11:02 AM.

[jd lj]

Once you've tuned your carbs to provide a suitable AFR then if necessary tweak the plug heat range to get them at the correct self cleaning colour/heat range. Don't worry about what everyone else is using, whilst that may give you a good starting point it may not be what your own set up requires.

[RallyRed]

Once you've tuned your carbs to provide a suitable AFR then if necessary tweak the plug heat range to get them at the correct self cleaning colour/heat range. Don't worry about what everyone else is using, whilst that may give you a good starting point it may not be what your own set up requires.

Agree JD...I have been running that car around a few tracks now for a couple of years, including  2 goes at Bathurst. ( = apprx 72 laps of the Mountain, at speed )

Reckon  if there was a drama, I'd know about it by now, lol

 

Ta for the feedback.