spark plug question
- Thread starter billybob
- Start date
finx
Member +
i wouldnt be touching iridiums on a 300BHP set up.
i cant remember what the specific differences are between bcp and bkr plug electrode designs are but by all accounts the bkr's are the preferred plug for the e series toyota engine.
power can be made and lost from the heat range and gap of your spark plugs and there is allot more to setting them up than most realize.
0.6 will work but you will need to get your tuner to work out what gap works best depending on your set up, as you have not provided specs or the pressures you plan to run its hard to judge what will produce the best results.
0.6mm is quite a small gap and whist that will help the spark when running big internal pressures you also need to be mind full of making the gap to small as this will reduce the size of the spark correspondingly. both will cost you power if not set correctly
you need to reach a happy median between getting a big enough spark to ignite your mixture properly and a gap small enough for the spark to jump without getting interfered with from big internal pressures.
If you have some dyno time to play with after the tune is all sorted get your tuner to do a few runs on 0.6mm gap until you get a defined power reading and then up the gap size until you get a reduction in power then drop it down a size and thats where it needs to be.
also if you have some spare dyno time get your tuner to try index the plugs, this can add anywhere from 1-5bhp on some set ups but there is loads of vairables to weather this makes a difference of not and is overlooked by a hell of a lot of tuners.
cheers
Ryan
i cant remember what the specific differences are between bcp and bkr plug electrode designs are but by all accounts the bkr's are the preferred plug for the e series toyota engine.
power can be made and lost from the heat range and gap of your spark plugs and there is allot more to setting them up than most realize.
0.6 will work but you will need to get your tuner to work out what gap works best depending on your set up, as you have not provided specs or the pressures you plan to run its hard to judge what will produce the best results.
0.6mm is quite a small gap and whist that will help the spark when running big internal pressures you also need to be mind full of making the gap to small as this will reduce the size of the spark correspondingly. both will cost you power if not set correctly
you need to reach a happy median between getting a big enough spark to ignite your mixture properly and a gap small enough for the spark to jump without getting interfered with from big internal pressures.
If you have some dyno time to play with after the tune is all sorted get your tuner to do a few runs on 0.6mm gap until you get a defined power reading and then up the gap size until you get a reduction in power then drop it down a size and thats where it needs to be.
also if you have some spare dyno time get your tuner to try index the plugs, this can add anywhere from 1-5bhp on some set ups but there is loads of vairables to weather this makes a difference of not and is overlooked by a hell of a lot of tuners.
cheers
Ryan
Last edited:
finx
Member +
yea the bcpr's or like i said above the bkr's which are more common and seem to be the preferred plug for the E series engines.
ill have a look in my application guide and find out what the differences are when i get time.
heat range depends on compression ratio internal cylinder temps and boost pressure.
a too hotter plug can in extreem case's cause pre ignition yet a too cold plug can attract conductive deposits of particulate which can reduce spark output and in extreem cases short out the spark current.
your safer running a colder plug but the heat range is also important to the strength of the spark and like the gap can have a positive or adverse effect on the sparks performance.
some more info on compression ratio and an idea of what kind of boost your going to end up running will help give us the desired heat range.
ill have a look in my application guide and find out what the differences are when i get time.
heat range depends on compression ratio internal cylinder temps and boost pressure.
a too hotter plug can in extreem case's cause pre ignition yet a too cold plug can attract conductive deposits of particulate which can reduce spark output and in extreem cases short out the spark current.
your safer running a colder plug but the heat range is also important to the strength of the spark and like the gap can have a positive or adverse effect on the sparks performance.
some more info on compression ratio and an idea of what kind of boost your going to end up running will help give us the desired heat range.
I ran 8s in my old gt at 1.4-6 bar on a td04, seemed good. Iridiums too. A tuner ive used said that in high power builds he tunes on copper cored plugs as they will burn out before the piston if things get hot, once tuned he switched to iridiums for a longer life if required.
Just found this info that i took off a supra forum a while ago, applies to most engines as a rule of thumb though, may help you with your choice?
Plug selection
Note - This selection list does not take Nitrous into account. If you have Nitrous go one grade colder than this table advises at your boost/performance level.
Rule of thumb
Iridiums should always come pregapped correctly - altering the gap can cause damage. If you test the gap and it isn't correct return them to the stockist and check they got in the right version.
Normally Aspirated
NGK - Standard - BKR5ES-11 (2382) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - V-Power - BKR5EYA-11 (2526) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - G-Power Platinum - BKR5EGP (7090) - gap to 1.1mm
NGK -Laser Platinum - BKR5EP-11 (3440) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK -OE Laser Iridium - IFR5T11 (4996) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - Iridium IX - BKR5EIX-11 (5464) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
Denso Platinum - PK16R11 - gap to 1.1 (but always check first)
Stock TT
NGK - BCPR6EP-11 - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - BKR6E (2756) - gap 1.1mm
NGK Iridium - BKR6EIX-11 (3764) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
Denso Platinum - PK20R11 - gap 1.1mm
Denso Iridium - IK20 - leave gap alone
TT @ upto 1bar
NGK - BCPR7ES (3330) - gap 0.9mm
NGK - BKR7E (6097) - gap 0.9mm
NGK - Iridium - BKR6EIX or BKR7EIX - leave gap alone
Denso Platinum - PK20R11 - gap 0.8mm
Denso Iridium - IK22 - leave gap alone
TT/hybrids @ upto 1.3bar
NGK - BCPR7ES (3330) - gap 0.7mm
NGK - BKR7E (6097) - gap 0.7mm
NGK - BKR8E - gap to 0.7mm
NGK - BCPR8ES (3330) - gap 0.7mm
NGK Iridium - BKR7EIX - leave gap alone
NGK Iridium - BKR8EIX - leave gap alone
Denso Platinum - PK20R8 - gap 0.7mm
Denso Iridium - IK22 - leave gap alone
Denso Iridium - IK24 - leave gap alone
Single Turbo/Big Twins @ upto 1.3bar
NGK - BCPR7ES (3330) - gap 0.7mm
NGK - BKR7E (6097) - gap 0.7mm
NGK - BKR8E - gap to 0.7mm
NGK Iridium - BKR7EIX/BKR8EIX - leave gap alone
Denso Iridium - IK24 - leave gap alone
Single Turbo/Big Twins @ upto 1.8bar
NGK - BCPR8ES - gap 0.6-0.7mm
NGK - BKR8E - gap 0.6-0.7mm
NGK Iridium - BKR8EIX - leave gap alone
Denso Iridium - IK27 - leave gap alone
Single Turbo/Big Twins @ 2+bar
NGK - BCPR8ES - gap 0.6mm ??? UNTESTED
NGK - BKR8E - gap 0.6mm ??? UNTESTED
NGK Iridium - BKR8EIX or BKR9EIX? - leave gap alone ??? UNTESTED
Denso Iridium - IK27 to IK31 - leave gap alone ??? UNTESTED
Plug selection
Note - This selection list does not take Nitrous into account. If you have Nitrous go one grade colder than this table advises at your boost/performance level.
Rule of thumb
Iridiums should always come pregapped correctly - altering the gap can cause damage. If you test the gap and it isn't correct return them to the stockist and check they got in the right version.
Normally Aspirated
NGK - Standard - BKR5ES-11 (2382) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - V-Power - BKR5EYA-11 (2526) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - G-Power Platinum - BKR5EGP (7090) - gap to 1.1mm
NGK -Laser Platinum - BKR5EP-11 (3440) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK -OE Laser Iridium - IFR5T11 (4996) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - Iridium IX - BKR5EIX-11 (5464) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
Denso Platinum - PK16R11 - gap to 1.1 (but always check first)
Stock TT
NGK - BCPR6EP-11 - gap is already 1.1mm at the "-11" signifies they should be set to this already.
NGK - BKR6E (2756) - gap 1.1mm
NGK Iridium - BKR6EIX-11 (3764) - gap is already 1.1mm at the "-11" signifies they should be set to this already.
Denso Platinum - PK20R11 - gap 1.1mm
Denso Iridium - IK20 - leave gap alone
TT @ upto 1bar
NGK - BCPR7ES (3330) - gap 0.9mm
NGK - BKR7E (6097) - gap 0.9mm
NGK - Iridium - BKR6EIX or BKR7EIX - leave gap alone
Denso Platinum - PK20R11 - gap 0.8mm
Denso Iridium - IK22 - leave gap alone
TT/hybrids @ upto 1.3bar
NGK - BCPR7ES (3330) - gap 0.7mm
NGK - BKR7E (6097) - gap 0.7mm
NGK - BKR8E - gap to 0.7mm
NGK - BCPR8ES (3330) - gap 0.7mm
NGK Iridium - BKR7EIX - leave gap alone
NGK Iridium - BKR8EIX - leave gap alone
Denso Platinum - PK20R8 - gap 0.7mm
Denso Iridium - IK22 - leave gap alone
Denso Iridium - IK24 - leave gap alone
Single Turbo/Big Twins @ upto 1.3bar
NGK - BCPR7ES (3330) - gap 0.7mm
NGK - BKR7E (6097) - gap 0.7mm
NGK - BKR8E - gap to 0.7mm
NGK Iridium - BKR7EIX/BKR8EIX - leave gap alone
Denso Iridium - IK24 - leave gap alone
Single Turbo/Big Twins @ upto 1.8bar
NGK - BCPR8ES - gap 0.6-0.7mm
NGK - BKR8E - gap 0.6-0.7mm
NGK Iridium - BKR8EIX - leave gap alone
Denso Iridium - IK27 - leave gap alone
Single Turbo/Big Twins @ 2+bar
NGK - BCPR8ES - gap 0.6mm ??? UNTESTED
NGK - BKR8E - gap 0.6mm ??? UNTESTED
NGK Iridium - BKR8EIX or BKR9EIX? - leave gap alone ??? UNTESTED
Denso Iridium - IK27 to IK31 - leave gap alone ??? UNTESTED
sx_turbo
Lifer
nothing wrong with iridium plugs,
there is plenty of people running huge power on them, dan briscoe was running 330bhp on a set,
i'm running 240@wheels, with more to come,
there is others but cant think right now, but copper cored plugs are definatley NOT better than iridium regardless of power
there is plenty of people running huge power on them, dan briscoe was running 330bhp on a set,
i'm running 240@wheels, with more to come,
there is others but cant think right now, but copper cored plugs are definatley NOT better than iridium regardless of power
finx
Member +
I have covered this before and will do so again.
There are numerous reasons why Iridiums aren't suited for high performance applications. i shal cover two of the main ones
All be it an extreme example but you dont see pro import drag cars running iridium plugs for good reason.
here is a quick overview
Iridiums are well suited to stock turbo applications and used as such because they offer a very fine spark due to the characteristic of the pointed electrode and because of the refined spark they last allot longer offering reduced ware on the earth and maintain a set gap for a longer period of time thus increasing service intervals and reliability (up to 100,000km on some engines) this is also their downfall in High performance modified engines.
Because of the fine tip on the electrode the amount of spark thats possible to be emitted is reduced in comparison to for want of a better work 'normal' tipped spark plug and its increased surface area which creates a fatter and greater spark.
Their other main letdown is in extreme pressure situations like High compression turbo applications, engines running high boost pressures and Huge RPM's
Because of their pointed tip which whist good in a low pressured combustion chamber (ie an unstressed stock or near stock engine) when confronted with a high pressure combustion chamber the pointed electrode makes it easier for the spark to trace and earth eradicably causing incomplete combustion costing power and in some cases can cause detonation and damage to internal components.
while iridiums as i said before last longer than your 'standard' type electrode when you have just spent thousands on an engine and set up and then tune a set of plugs every 6 months or year is allot cheaper than a dead engine because of pre ignition
as i have said spark plugs are hugely underestimated by a great percentage of car enthusiasts and while with modern engine management systems and fuel injection such specifics as i have been disusing are less important to the every day running of an engine they still contribute allot to High performance applications where your trying to squeeze the maximum possible from a set up. HP gains are there to be had by those that bother to spec and set up theirs correctly to their application
cheers
Ryan
There are numerous reasons why Iridiums aren't suited for high performance applications. i shal cover two of the main ones
All be it an extreme example but you dont see pro import drag cars running iridium plugs for good reason.
here is a quick overview
Iridiums are well suited to stock turbo applications and used as such because they offer a very fine spark due to the characteristic of the pointed electrode and because of the refined spark they last allot longer offering reduced ware on the earth and maintain a set gap for a longer period of time thus increasing service intervals and reliability (up to 100,000km on some engines) this is also their downfall in High performance modified engines.
Because of the fine tip on the electrode the amount of spark thats possible to be emitted is reduced in comparison to for want of a better work 'normal' tipped spark plug and its increased surface area which creates a fatter and greater spark.
Their other main letdown is in extreme pressure situations like High compression turbo applications, engines running high boost pressures and Huge RPM's
Because of their pointed tip which whist good in a low pressured combustion chamber (ie an unstressed stock or near stock engine) when confronted with a high pressure combustion chamber the pointed electrode makes it easier for the spark to trace and earth eradicably causing incomplete combustion costing power and in some cases can cause detonation and damage to internal components.
while iridiums as i said before last longer than your 'standard' type electrode when you have just spent thousands on an engine and set up and then tune a set of plugs every 6 months or year is allot cheaper than a dead engine because of pre ignition
as i have said spark plugs are hugely underestimated by a great percentage of car enthusiasts and while with modern engine management systems and fuel injection such specifics as i have been disusing are less important to the every day running of an engine they still contribute allot to High performance applications where your trying to squeeze the maximum possible from a set up. HP gains are there to be had by those that bother to spec and set up theirs correctly to their application
cheers
Ryan
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billybob
Untrusted Seller
hmmm getting confussed now ?i thought that the copper ones are better for spark control
finx
Member +
Im not referring to copper plugs specifically..
I hear what you are saying but It is not only the compound of material used its also the shape of the electrode
I realize there are different shape iridium plug electrodes,
the ones in question that are mainstream, available at your local parts store and also which are of the type that 99% of people on this site are using or likely to be sold if they are advised to go and get iridium plugs (this happends often and isnt backed up by a good explanation) are the ones i am advising against in the specified situations described.
more sophisticated 'race' plugs are not easily attainable to most people
There is obviously more to it that what i have stated but i would be here forever explaining every last fine detail.
cheers
Ryan
I hear what you are saying but It is not only the compound of material used its also the shape of the electrode
I realize there are different shape iridium plug electrodes,
the ones in question that are mainstream, available at your local parts store and also which are of the type that 99% of people on this site are using or likely to be sold if they are advised to go and get iridium plugs (this happends often and isnt backed up by a good explanation) are the ones i am advising against in the specified situations described.
more sophisticated 'race' plugs are not easily attainable to most people
There is obviously more to it that what i have stated but i would be here forever explaining every last fine detail.
cheers
Ryan
finx
Member +
curious it appears someone has deleted their last post. ??
I hear where your coming from, but dont totally agree.
not sure where power came into it, im not prescribing a plug for a certain power range that would be idiotic . the plug suits the engine and what you are asking of it in terms of heat, airflow combustion pressure and is also directly related to compression
please back up you claims with some hard info as i have done, im all ears
cheers
Ryan
I hear where your coming from, but dont totally agree.
not sure where power came into it, im not prescribing a plug for a certain power range that would be idiotic . the plug suits the engine and what you are asking of it in terms of heat, airflow combustion pressure and is also directly related to compression
please back up you claims with some hard info as i have done, im all ears
cheers
Ryan
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finx
Member +
sorry if you feel that way i dont see where this turned this into an argument.
i hadnt even replied before you deleted your post so struggle to see how you would come to that conclusion and reasoning for the removal.
Im only trying to prove my point of view / theory and opinion. im all for people to express their own opinions and knowledge especially if they can back it up with an explanation that proves the point
nit picking holes now but the reason i stated the 300hp is because those kinds of outputs on a small capacity engine require big pressures to be attained which is directly related to my points of emphasis
cheers
Ryan
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popsy09
Munster Area Rep.
this thread is exactly what i have been looking for my tuner said heat range 8 iridiums and gapped to .6 , im heading back down monday to get another run at 1.6 bar with the new plugs and ill let ye know how it compares and what gap i ended up with etc ,
finx you know way to much about cars lol great to have someone with your knowledge on the site
finx you know way to much about cars lol great to have someone with your knowledge on the site
twincamdill
Fresh Recruit
can this be mead a stiky? Took me ages to find good spark plug info