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they look like completely different mould, would be interesting to test.

L67PSI wrote:I fitted a new set of NGK BPR6EF-13 into my VT L67 today. It pays to check the gaps as they were all approx 1.2mm. Gapped them all to 1.3mm and will test it out.

Just of note i have been running 1.7mm gap on my Ecotec N/A for a while now with these Gorst Coils, previously when i tried a gap that large i had alot more knock induced, currently ive noticed no knock compared to stock 1.5mm gap and fuel economy has been improved on average 1L/100km, airflow and MAF readings are still maintaining the same, so im not seeing any loss of power per say but better economy helped by the larger gap and stronger spark.

L67PSI wrote:I fitted a new set of NGK BPR6EF-13 into my VT L67 today. It pays to check the gaps as they were all approx 1.2mm. Gapped them all to 1.3mm and will test it out.

Just an update. Have been running this setup for a couple of months with no issues.

nice!

I haven't tested it myself, but been told when running more the 13psi boost to run less than 0.8mm gap as it blows the flame out.

Interesting to know a bigger gap on n/a with coils that can support it will increase fuel economy, you'd have to monitor gaps closely after 20,000kms you'd think to make sure they don't get too big unless platinum/iridium?

Larger gaps that can be supported will always provide better economy, simply as it reduces the amount of misfire events. Misfire inevitably cause loss of fuel and loss of power/torque, how much depends on how good the initial design is but that said, they are only small gains. eg. at most maybe 2-3%.

im just using the standard Holden Copper plugs here, i usually run them for 30k and swap a new set in, will see how they look after 30k and it was a new set that went in at 1.7mm gap, economy is still better by about 1L/100, they are about 5000km on now.

As far as power, cold intake temps, airflow and 0-100 times are still the same, Hot weather >30c intake temps airflow is up comparing 5800rpm WOT, especially on a stinking hot day with 40c + intake temps the drop between hot and cold is not as bad, by the logs the drop would be about half of what is used to be, i run 7.5sec 0-100 normally and on a hot day it'd go back to 8seconds, it still keeps around 7.5 now, nothing huge but the small efficiency gain from the larger gap and stronger spark help keeps the airflow up.

vlad01 wrote:Larger gaps that can be supported will always provide better economy, simply as it reduces the amount of misfire events. Misfire inevitably cause loss of fuel and loss of power/torque, how much depends on how good the initial design is but that said, they are only small gains. eg. at most maybe 2-3%.

Recently on my ecotec in the hilux 4wd I closed the ngk plug gaps up to 1.3 from the 1.5 standard setting. I now have noticed a lot more low speed under load missing going on. So would going back to the standard 1.5 setting help stop the low speed missing ?

yes it should. Also check coils. I had intermittent miss on 2 cars before and always was a weak coil I found.

Agree most likely dud coil...all 3 coils tested fine on my vp yet still had intermittent miss when hot....only notable difference was arcing in lead & spark colour was slightly different to other 2 coils.

Replaced dud with another coil it went away so changed all 3 at same time with new delphi it was smooth as a buick could be lol