That's why they need a high energy ignition with a fast rise time - to fire them when fouled. Being fouled is almost "normal" for them. In many applications - like outboards - they are chronically wet and/or fouled. The intention was to have a plug that would keep firing after prolonged very low speed running (eg. trolling) yet not preignite when running at full throttle and high loads. The combination of CDI and surface gap worked well, and I've had success using them with methanol two-stroke bikes that will continue to fire perfectly no matter how wet and oily they are.OldsMan wrote: ↑Fri Jul 25, 2008 11:49 am Downside to surface gap sparkplugs, is they will foul faster as they run cooler.
Surface gap spark plugs
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Re: Surface gap spark plugs
Would I be wasting my money buying a set of surface gap plugs to use in my 2012 Mustang 3.7L V6? Everything under the hood is stock, I've made no modifications to it... yet.
Re: Surface gap spark plugs
don't bother putting them in a car engine expecting any performance benefit
I have used surface gap plugs before in 2 stroke engines where the spark plug is a factor for the combustion chamber shape and volume
I have used surface gap plugs before in 2 stroke engines where the spark plug is a factor for the combustion chamber shape and volume
Re: Surface gap spark plugs
The ONLY way to find out if a particular spark plug is an improvement in your engine....is to try it.
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Re: Surface gap spark plugs
I used them a lot in 2 stroke outboard motors and tried them in a tall dome big block Chevy. They work well if the ignition system is up to it.
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Re: Surface gap spark plugs
I think the reason they are used in 2 strokes is because the piston comes so close to the head there is no room for the ground strap.i used to drag face snowmobiles on 1/4 mile on ice and the piston to head clearance was .050-060.151.8 mph was my mod sled 138.2 was my improved stocker.maybe bragging a little but won many trophy and championchips.this was1994-98.
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Re: Surface gap spark plugs
I used stock coils never any problems. Burned a couple down you don't know how far you can push it unless you do
274hp 1000 cc.
274hp 1000 cc.
Re: Surface gap spark plugs
Ran them in a high compression 17-17.5:1, all iron(block and head no water), alcohol, NA, MFI, pulling I6 based on what NGK recommended for this application. Seemed to work ok, this was a while ago but as I recall they were expensive plugs.
Tractor Puller, 1959 IH 460 with 430cid NA Alcohol Inline 6 started its life as a D282
The only replacement for displacement is RPM!
The only replacement for displacement is RPM!