Spark plug gap

[N2ORBT]

Seems every one runs different gaps on their plugs. Im getting a little bit of break up on the top end (20lbs boost, alky kit) and after researching most of you recommend running a tighter gap any where from.28-.32 to try and eliminate the spark being blown out. I just bought CR43TS pugs and plan on gapping them at .30 but out the box they are gapped at like .42. This may seem like a silly question but how am I suppose to decrease the gap? Bend the electrode slightly? Or did I get a faulty bunch.

 

[Boost231]

i have run .032 gap all the way to 28psi. At 20psi of boost you shouldn't be getting spark blow out unless there gap at like .045

anyways to gap them tighter i lightly tap them on the ground then check every time with a feeler gauge. thats how i have done it for years.

gap your plugs to .032 if your having issues at 20psi you need to find the cause. gapping tighter is a trouble shooting thing some of us do to see if its ign. realated

 

[1984 t-type]

I set my spark plug gaper on something solid and tap the plugs on it , dosent take much tap it lightley once or twice and check

 

["Turbo-T"]

To close the gap I usually just get a good grip on the plug insulator/base and firmly push the tip of the ground electrode on something hard while watching the gap close up. I try not to get them too tight, just so that I can be able to slide a feeler gauge in there.

 

[Dino1]

You guys kill me, tapping the plug on anything, the ground or something solid is primitive. A good spark plug gapper is going to have the tang to bend the electrode. or going to gap a wide gap to the desired gap. tapping ceramic on a hard surface is just plain stupid.

 

[shepardsls]

stupid has worked for thousands of people thousands of times

 

[TR Custom Parts]

Right way!

 

[jasjamz]

Seems every one runs different gaps on their plugs. Im getting a little bit of break up on the top end (20lbs boost, alky kit) and after researching most of you recommend running a tighter gap any where from.28-.32 to try and eliminate the spark being blown out. I just bought CR43TS pugs and plan on gapping them at .30 but out the box they are gapped at like .42. This may seem like a silly question but how am I suppose to decrease the gap? Bend the electrode slightly? Or did I get a faulty bunch.

How did you determine it was spark blow out? .28-32 is fine the more boost you run you may need a tighter gap. For 20 psi .32 is fine. Do you have a wideband or scanmaster? Spark blow out can show things getting rich.

 

[N2ORBT]

Thanks for the input guys. I ended up putting it in a vice and slowly compressed it until the desired gap. I didnt really pound it on the ground so does that make me part for the "stupid works" crowd?

I have not isolated the break up to being the spark plugs and am only doing this to narrow down the list of culprits.

 

[salvageV6]

Sometimes those gappers work sometimes they just get chewed up and bend the cheesy metal also.

Country of origin may have something to do with that.

Tapping them on the radiator support of an American made car from the 50's to the late 80's has worked for me 40 years now.

It's not like you're smashing them down on it, it's a controlled calibrated tap. :biggrin:

I'm not sure I'd put one in a vice however.

 

[GNVYUS 1]

I'm .035 at 25psi and won't lower it until I feel the horse bucking me out of the seat.

Spark blow out can be narrowed down to spark energy, I'd look at your ignition system as I can't see how a new to 50k mile coil pack couldn't light 20psi at .030.

 

[Dabigguy]

x2 on the ignition system....how old are your wires? Test them with an ohm meter.