Whats the standard gap on NGK PFR7B

Zheiko

Octane Boostaholics
I have talked to aonghus from AP-Performance, and he told me to get a new set of these and gap them to 0.65mm.

I bought the measuring device, and from what I have seen, it already looks like 0.65mm, so I was wondering, is that the standard measure? Or is it 0.7mm and I just looked wrong?
 
I would have thought 0.9-1.1mm is standard on NGK's. Mine are gapped to .6mm at the moment, hard to see by eye 0.3mm to be honest
 
0.7mm on the 7b platinums.

Never ever have an issue at factory gap.

And remember do not gap iridum plugs as make the tip brittle.
 
yea, they are 0.7mm, how big of a difference is 0.65 and 0.70?

edit: obviously, the difference is 0.05mm, I mean performance-wise - could that cause any issues if I put .7 while car was mapped for 0.65?
 
No difference plugs not the issue I'd say. More likely a coil breaking down

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boost can blow out the spark that's why Aonghus sets them to .6


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Must be some boost. Never had any issue with 7bs on standard out of the box gap.. I've often checked them and haven't found any discrepancies in them either..
 
He is right 100%. The gap should be 0.6-0.7

If you missing as you get into higher boost, especially when it's cold then it's your plug gap. On the stock car with stock boost gap can be std but not if you have mods and higher boost. I run a .7 gap cause I've had this problem before with pass turbo cars. The saying is the spark gets blown out.

Im also glade to hear he said that cause I'm going to do a big build next year and needed a tuner, he was recommended.
 
As Dave said: std gap 0.7mm (and do not gap the iridium ones as it kills them)

0.6, 0.65, 0.7mm ... All are common gap sizes for forced induction applications, and realistically very little in it and you would not notice any significant difference within that range.

0.9-1.1mm gaps are more common for NA cars, not forced induction... which is indeed because under boost conditions it will take more energy for the spark to jump the gap.

@Zeiko: if you have new plugs typically the gaps quite accurate out of the box. You checked and saw it was somewhere around the 0.65-0.7mm mark... which is fine. If you still have the issue after fitting new plugs with gaps like that then Dec is spot on and sounds like one or more coilpacks are getting weak --- and / or bad earthing can also be a (contributing) factor (these are not new cars and earthing can get corroded which can also affect spark). Whether coilpacks or earthing... it would be more evident at higher revs and/or boost as there is more resistance for the spark to jump the gap, which takes more energy. I'd get the coilpacks checked / have new ones fitted... and clean up the earth strap connections on either end as part of the job. As for not showing error codes: only if one or several totally fail and the issue is there for a prolonged period would you expect to see a diagnostic thrown up... but if only happens for a few seconds during driving (as you'd back off when it happens) it wouldn't typically throw a code immediately.
 
Thanks for input guys, very helpful. I will be doing oil change and will check/replace the plugs, if I dont see any improvement in drive, I will start investigating the Coil Packs. Giving the rule I am following - if I need to replace something, it may as well be an upgrade, can you recommend some good Coil Packs?
 
As it may not be either.

You could try another set of coil packs just to eliminate it.

If it doesnt you havent wasted money on parts you didnt require
 
Yeah shur what would Aonghus know![emoji85]


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i haven't a clue what he does or doesn't know.. I can say that I have ran Pfr7b plugs from standardish power up to probably close on 500 and I never had to adjust gaps... I always check them but they always have been consistent in their gaps.. boost from memory would have been anywhere from 1.3 up to 2bar

Look at the figures, we are talking about 0.05 less than standard gap... it's nothing.
But do check the gap for consistency as they do get dropped and I have seen guys tapping them on counters as the weight in auto factors lol
 
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same

Have ran Subarus 300-520bhp upto 1.9Bar. At 0.7mm factory gaps.

Without issue ... quoted ...


as above ... with no issue either ...

if you search ngk website ul find an article on temp ranges ect .. 7b's are not needed in a lot of cars even with more boost .. it says that heat range change is only needed when compression is changed . irc ...
 
The 7,s (7G) are factory plug on jdm sti's from 2002 blob twinscrolls onwards.

Also at .7mm

In the OP case here. As Ali said. On a WRX still running the TD04 the 6B' be perfectly fine. And again at .7mm

This is a whole lotta focus on something that is actually not needed to be.
 
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boost can blow out the spark that's why Aonghus sets them to .6


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never heard of this

its not a flame its electricity jumping the gap, more likely a coil or lead breaking down.
the plug ignites at in around top dead centre give or take a few degrees when valves are closed so boost has no impact what ever is in the chamber is in there however under compression the pressures are multiples of what any boost would be so maybe this is an issue but as far as the boost blowing it out that is a load of cock but am open to correction.
 
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