INFO: Spark Plug Gap and TSB

[dalinxz]

Well as some of you may know my uncle is a mechanic and often takes courses to update his training, well today he was telling me that NGK had issued a TSB and gave me the TSB I will have them scanned in tommorrow and you guys can see but apparently since all the new fuels contain ethanol and since our engines aren't designed for ethanol we lose mpg and it's bad for emissions. The TSB says to lessen the gap by .010 therefore since ours is 0.42 it would become 0.32, although it says never to lessen it less than 0.35 therefore our gap would need to be changed to 0.035.

Therefore change your gaps to 0.035, it also talks about people not adjusting the plugs after adding CAI or short rams with the increased air flow it leads to leaner conditions blah blah blah, I will scan them in. It's said to improve mpg and power and also for every 50hp increase you have to increase the type of spark plugs to two ranges cooler or something anyhow once I scan the sheets in you guys can tell for yourselves.

EDIT: Will be posted tommorrow June 11, 2007 at around 2pm-5pm
EDIT2: As promised Pictures are posted below

[Blkblurr]

Sounds like some good info. Don't forget ot post it.

[MessyHonda]

i just have my NGK gaped at .50....il try to change the gap next time at tune up. i have a CAI, cam gear,and full exhaust...headers coming soon

[ahmad89]

This goes for any car now days? to clarify this will increase our mpg? my spark plugs are gapped at 1.1 mil. and .050 inches. I'll shorten it when i change my plugs. Thanks for the info.

[dalinxz]

ok sorry haven't had time to scan in the TSB yet will do it tommorrow I promise I just realized its a sticky so its important, but dont do anything yet and 0.050 is quite high, way too high its supposed to be 0.042, I found my mileage has improved, power remained similar I mean maybe a little more torque but not much but I think that's because I still haven't changed to a cooler range. But I'll scan the TSB tommorrow and you guys can all check it out. But basically you need to regap it to 10 thousand less so 0.042 to 0.032 but 0.035 is the lowest you should go and your supposed to increase the heat range to 2 ranges cooler for every additional 50hp so lets say the model is NGK BRP5EGP then 2 ranges would be BRP7EGP but I'll scan them tommorrow I Promise lol.

[dalinxz]

It's meant for all cars, my uncle was telling me even new cars are supposed to be regapped because the dealers aren't changing it either since they aren't all aware of the TSB and when they test they aren't using gases with ethanol, but with those cars the ECU can adjust it to a certain extent but ya it's for all cars not Hondas only.

[dalinxz]

i just have my NGK gaped at .50....il try to change the gap next time at tune up. i have a CAI, cam gear,and full exhaust...headers coming soon

CAI is extra airflow requiring gap to be changed
as does the fuel with ethanol
Basically for every 50hp you have added you need the gap changed and 2 ranges cooler. Ill scan these in the morning once I wake up.

[dalinxz]

as promised pictures are posted!!!

[ahmad89]

i need to re-gap mine to .040 but its way too hot to even sit outside.

[Strugglebucket]

since this is stickied, i would also add that if you disable your egr you need to run a step colder.

[steveko]

Has anyone had any real world results from changing you're plug gap and a step cooler.

[Pico]

Has anyone had any real world results after this post curious.

[88Accord-DX]

Spark plug gap doesn't make a plug run colder anyway it's set. Certain plugs are make to run at a higher resistance, aka "hotter".

[A20A1]

I thought the plug heat range was how much it is exposed to heat and how good it is at transferring that heat away.

[steveko]

I did'nt say that reducing the gap makes it run cooler.I'm talking about getting new plugs 1heat range cooler and closing the gap as suggested. I'm referring too the post IMPORTANT at the top of the technical page.

[steveko]

What knowbody has any answers or results from this post.

[steveko]

From what I took out of the article .035 is the lowest you want to go gap wise.I don't know about going 1 heat range cooler in you're application but possibly mine.Also if memory does'nt fail me I think you're leaning the car out with any modification air filter,exhaust,etc.you would have too adjust the fuel to air ratio.

[clark_486]

"0.050 is quite high, way too high its supposed to be 0.042, "

Pretty sure it says 1.0 +.01 on the hood of my car; ie .050

[rfiks]

if it aint broke then dont tryda fixit!!!

[bkdsah]

So is there any official word on this? Or does it depend on need/preference/situation? I replaced plugs and wires yesterday and gapped them at .04. I remembered this link saying .035 was where it should be at, given all the circumstances. However the guy at Autozone told me to gap them at .044. Figured I'd split the difference and thats what they're at right now.

Good, bad, any suggestions?

Any help would be great, thanks.

[Oldblueaccord]

Really this is/was unproven. I don't want to comment any farther on it since it is a sticky so someone important felt it needed to be at the top the first day it was posted. Sounds to me like NGK had some problems and an engineer got in a panic and cover his ass with that little TSB.

I run up to 30% ethanol at any one time in the last 2 years and have not found any problems with my spark plugs. I recorded a 30.6 mpg last week after running 3 tanks of just 87 octane fuel (10% ethanol) at 29 mpg.

1.0mm=.039 inches just to correct another factual mistake posted.

wp

[POS carb]

STOCK
BPR5EY11 = 6937

1 STEP COLD
BPR6EY11 = 6261

This is weird because I was running the colder 6261 plugs and I melted a valve, when I showed one of the mechanics who frequents the shop he asked me if I was running the correct-heat plugs. I also run 87 octane, no egr, and abuse the car daily.

[Oldblueaccord]

Really this is/was unproven. I don't want to comment any farther on it since it is a sticky so someone important felt it needed to be at the top the first day it was posted. Sounds to me like NGK had some problems and an engineer got in a panic and cover his ass with that little TSB.

I run up to 30% ethanol at any one time in the last 2 years and have not found any problems with my spark plugs. I recorded a 30.6 mpg last week after running 3 tanks of just 87 octane fuel (10% ethanol) at 29 mpg.

1.0mm=.039 inches just to correct another factual mistake posted.

wp

im still running them still mixing e 85 and gas. Time to bury this one.


wp

[2geeSEi]

Don't do it! I just tried this for myself. The plugs were gapped at 1.1mm or .044" and ran really smooth. Changed the gap to .035", I won't say the idle was rough, just kind of lumpy. Also, when I would push the gas pedal, the engine would lurch so much even my steering wheel would jolt. Needless to say, I never even made it out of the garage like this. Changed the gap back to .044" and all was right in the world again. There may be something to be said for the heat range thing though. I have a CAI and cat back, and the plug insulators are white, not tan (although they don't have many miles on them). I may go with BPR7ES instead of BPR6ES next time I change them.

[niles]

FYI for those who want to try one heat range colder spark plugs, here are some part numbers:

7082 (BPR5EGP) heat range 5 - NGK Platinum standard plug
7084 (BPR6EGP) heat range 6 - NGK Platinum one heat range cooler