spark plugs

Corey

Active member
From what i under stand:

The colder the plug, the better able it is to disipate heat away from the tip of the plug.

This is good if you are running higher boost settings, because it will help stop detonation.

But if you arnt, then the colder plug wont be able to burn off the carbon deposits, causing it to foul up.

So, Stock range for the NGK is 6, most people with higher than stock boost seem to run 7. I think thats when they run 12-14 psi.

I dont hear of many people running more than 7 heat range.
 

tw2

New member
I have never heard of anyone running more than 7 although I don't doubt that many do. 6 is good up to around 14. 7 to about 22 any then its anyones guess as to what works best.
 

BriinumsBo

New member
what do you mean by "foul up"? my english knowledge is beyond this one :D is it bad for spark plugs or for engine? or for both? does it make engine like this? :)
(Corey Darling pic)
DSC02272small.JPG
 

etantshi

Moderator
"Foul up" simply means the build up of carbon deposits to the extent that it inhibits the effectiveness of the sparkplug to give you a strong arc across the electrode.
 

BriinumsBo

New member
smack me in the head :) lets make the question simple - SHOULD I get some OEM type grade6/7 instead of NGK Iridium gr.8?
I got these slightly used from V6 engine, as one of the 6 had gone. Probably I wont sell these also.. so should I get some other grade plugs instead or it is ok to keep these as long as the engine doesnt hesitate (misfire)? will these damage or mess up the engine? i dont care about the plugs
if its ok to drive with these, i`ll just get another set of plugs and carry them in the car if suddenly some plug dies or smth..
thanks :D
 

Corey

Active member
Yes, on stock boost, you should be running NKG grade 6. Denso has different temp numbers. Each plug manufacture uses a different system.

The stock plug part numbers are in the BGB. And i think there were mentioned earlier in this thread.

Toyota suggests either the NGK Double Platinum Plugs, or the Denso Platinum.

They dont mention iridium, or copper.
 

Hotrodhendrix

New member
Ok so what is suggested for a decently upgraded alltrac? It should be about 400 bhp around 18-20psi... It will stay around 12psi for normal driving more than likely. I dont mind changing them often sence it wont be driven very much.

Also I have nology hot wires. I know I know im going to try them. I had purchased them before reading up on them. If they cause a problem I have an extra set some where in the garage. Do these need a specific kind of plug?
 

wizzards581

New member
read on magazine that copper and platinum plugs make same hp, but platinum will last alittle longer, iridium gained a +2hp.

this was done with a dyno. iridium is said to give best gas milage with most hp... i think im gona have to go with this.
 

$200GT-4

New member
furpo":2xkbxv0w said:
The only reason you want to go to a colder running plug is because you are seeing signs of the plug overheating. This can be seen as 'chalking' around the electrode.

Roger

I assume this "chalking" to be a white residue? Just on the edges of the electrode? Do you have visual aid? I'm all about running the hottest plugs feasible. Would a hotter plug limit your ignition timing advance?
 

Hotrodhendrix

New member
Hotrodhendrix":zt89ekiu said:
Ok so what is suggested for a decently upgraded alltrac? It should be about 400 bhp around 18-20psi... It will stay around 12psi for normal driving more than likely. I dont mind changing them often sence it wont be driven very much.

Also I have nology hot wires. I know I know im going to try them. I had purchased them before reading up on them. If they cause a problem I have an extra set some where in the garage. Do these need a specific kind of plug?

So should I go one stop colder?? :shrug:
 

BriinumsBo

New member
definitely go grade 7!. for 400hp i guess you should even need grade8. Come to Latvia, i have ngk iridiums 8, bring some grade7 with you, and trade is done :D
 

Hotrodhendrix

New member
BriinumsBo":lsaauo8m said:
definitely go grade 7!. for 400hp i guess you should even need grade8. Come to Latvia, i have ngk iridiums 8, bring some grade7 with you, and trade is done :D

Sounds good. Is Lativia a town in texas? :p
 

BriinumsBo

New member
almost.. somewhere on the other side of globe :D
OT :smokes:

btw, can colder grade plugs cause car run into bad gas mode? (TVIS open, TVSV closed all the time)
 

BriinumsBo

New member
hello there!

I`ve been driving around for a year with NGK Iridium grade 8 and chose to switch. My friend needed grade8 (on his 400hp S13) so we just swapped. He thought he had grade 7, but on the plug the only number is 6 (smth like BKR6E or similar).
I`m not sure, maybe it is worse than it was before.
But what I did notice (what I really knew I had to check) is that AFR gauge now reads different. Though its narrow band, when I go WOT, its different, much more rich!! does that mean that it burns less? I did short TE1 and E1, so maybe that is the reason, i drove it only some 15minutes. Since there is only one way for oxygen to escape, spark plugs shouldnt change air:fuel ratio that goes into exhaust?
 

gpmarzan

New member
BriinumsBo":26b3gxer said:
hello there!

I`ve been driving around for a year with NGK Iridium grade 8 and chose to switch. My friend needed grade8 (on his 400hp S13) so we just swapped. He thought he had grade 7, but on the plug the only number is 6 (smth like BKR6E or similar).
I`m not sure, maybe it is worse than it was before.
But what I did notice (what I really knew I had to check) is that AFR gauge now reads different. Though its narrow band, when I go WOT, its different, much more rich!! does that mean that it burns less? I did short TE1 and E1, so maybe that is the reason, i drove it only some 15minutes. Since there is only one way for oxygen to escape, spark plugs shouldnt change air:fuel ratio that goes into exhaust?

I dont think that a narrow band can tell a rich and a very rich condition. from like 14:1 and richer, the output voltage is the same of 1V while vice versa when 15:1 and leaner of near 0V. So when you say its much more rich now, your a/f ratio must be in the 14.x:1 zone before at wot. Like people say, narrow band o2 gauges are nothing but a dance show.
 

timmey

New member
I am running NGK copper BKRE7's at 0.20 gap at 10psi which I guess is a bit cold for what I am making (stock st185, st205 w2a IC, 10psi, 3" catback and airbox delete/cone filter. I am having occasional boggy response sometimes.

I'll try the 31 gap on some copper 6s next time. I used to run Iridium 6's but a whole bunch of people crap all over the Iridiums. I didn't have any problems with them, but just tried copper one time for the hell of it and just went with that.

Any more conclusions or opinions on Iridiums? Mabye I'll go back to them.

Cheers,

Timmey
 

timmey

New member
After more reading, and swapping to BKR7Es at stock gap a long time ago:

Always say NO to a mostly-honda tuning shop when they say 0.20 gap will fix your idling issue when they're changing your plugs.

:|

Timmey
 
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