best spark plugs for JZA70 motor
- Thread starter mk3tattoos
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Iridium plugs have a fine wire to PREVENT spark blowout. The finer the tip the easier it is for the spark to jump the gap. A larger tip does nothing but allow more wear surface on copper core plugs so that they have a longer wear life (typically 15-25K miles). They also make fine wire copper core plugs (NGK racing series, they end with a "G"... ex BPR6EG instead of BPR6ES) for racing that are designed to only last a few thousand miles. Motocross racers use them alot.
The advantage of Iridium being used for plugs is that you can gap them a little larger than you would a copper plug (ex, .032 instead of .028) so that you have a larger spark (that's just as strong), and have better service life due to the super hard wearing nature of iridium. I usually replace performance style iridium plugs every 30-45K miles. "high mileage" iridiums have a larger center electrode and last longer (100K), but they can't be gapped as wide for a larger spark cause the spark will blow out.
As for iridiums being crap cause they crack....
If you have the tip of the iridium plugs breaking off, you are probably gapping them incorrectly or they were dropped (hard) by someone before you got them. Iridium is as fragile as porcelain. If you bump or pry on the iridium tip with the plug gapping tool it will crack and eventaully fall off. If you use the correct gapping tool (wire type) and gap adjusting tool (it pries only on the ground strap) you won't have problems with the tip cracking off. I've installed hundreds of iridium plugs and have never had one with a problem.
Having said that... I use NGK copper core (and always have in all my cars except the speed3 which has fine wire iridium plugs stock, with a 35K change interval). I like changing my plugs every 10K even if they aren't worn out. I can keep an eye out for problems (oil burning, lean conditions, rich conditions, etc..) by looking at the plugs more often than if I changed them every 20K or more. Plus I don't have to deal with plugs that are seized into the head from being in there for 100K untouched.
The advantage of Iridium being used for plugs is that you can gap them a little larger than you would a copper plug (ex, .032 instead of .028) so that you have a larger spark (that's just as strong), and have better service life due to the super hard wearing nature of iridium. I usually replace performance style iridium plugs every 30-45K miles. "high mileage" iridiums have a larger center electrode and last longer (100K), but they can't be gapped as wide for a larger spark cause the spark will blow out.
As for iridiums being crap cause they crack....
If you have the tip of the iridium plugs breaking off, you are probably gapping them incorrectly or they were dropped (hard) by someone before you got them. Iridium is as fragile as porcelain. If you bump or pry on the iridium tip with the plug gapping tool it will crack and eventaully fall off. If you use the correct gapping tool (wire type) and gap adjusting tool (it pries only on the ground strap) you won't have problems with the tip cracking off. I've installed hundreds of iridium plugs and have never had one with a problem.
Having said that... I use NGK copper core (and always have in all my cars except the speed3 which has fine wire iridium plugs stock, with a 35K change interval). I like changing my plugs every 10K even if they aren't worn out. I can keep an eye out for problems (oil burning, lean conditions, rich conditions, etc..) by looking at the plugs more often than if I changed them every 20K or more. Plus I don't have to deal with plugs that are seized into the head from being in there for 100K untouched.
Good info for sure
I got my iridiums in, car runs alot better, but still has the misfire, i tested my coils and they didn't test too well. So i'm getting new coils.
I got my iridiums in, car runs alot better, but still has the misfire, i tested my coils and they didn't test too well. So i'm getting new coils.
OneJArpus;1615848 said:
what brand of iridiums did you go with? hope the new coils stop the misfire, let us know how it goes.
I was racing a scion TC and pawned him pretty bad I think it was turbo refit because it was faster then my oem scion tc for sure.
Anyways my car started to run like a WRX found one of the ground straps on my #6 plug looks like it broke off by the tip maybe a 1/8" x 1/8" little square ran a magnet through and a shop vac while turning the motor over should have grabbed the little bit.
Did I spike lean to do that? I have also been getting an E8 on my LC-1 here and there but the stinger doesnt adjust to an O2 so I am fine the tune is normaly pretty good.
Any Ideas on why the ground arm would brake off like that?
Anyways my car started to run like a WRX found one of the ground straps on my #6 plug looks like it broke off by the tip maybe a 1/8" x 1/8" little square ran a magnet through and a shop vac while turning the motor over should have grabbed the little bit.
Did I spike lean to do that? I have also been getting an E8 on my LC-1 here and there but the stinger doesnt adjust to an O2 so I am fine the tune is normaly pretty good.
Any Ideas on why the ground arm would brake off like that?
so did you get it running back to normal? i have seen a alot of scion tc's super charged on the track, and they were pretty quick.
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hey guys i just bought some some spark plugs NGK BCPR6EGP for my 1jz supra, but have no idea which set of spark plug wires to buy? The guy at oreillys said they had some tailor spark plug wire set but i was a little unsure. I run a stock 1jz so i want something that'll get the job done.
Wow then I have no idea what/where to buy I'm unsure of brand names.......How do the coil plugs work? I'm not even sure if I even need to replace them, someone suggested it.
mk3tattoos;1615889 said:
IK20's IIRC, new coils on order i'll have them by friday. Sat i'll install and see how it goes. I'm going to replace the iridiums again, i think i fouled them out because now its blowing out from 4k to 5K, thats what i get for driving 200 miles on a super rich setup lol.
legionarius;1622637 said:
there's really only one way to go and that is OE Toyota coilpacks.. but you have no reason to replace or modify them if you car is running properly.
as far as how they work: http://www.aa1car.com/library/copign.htm (this is a much better explanation than I could give)