cut back plugs?
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From: Clarksville Tennessee
cut back plugs?
This is my first time using cut back spark plugs. My question is should I gap them or install as is? If they need to be gap, should I use the factory gap or go with a larger gap?
rssshen vette
rssshen vette
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From: Clarksville Tennessee
Originally Posted by rocco16
Yes, gap your plugs.......
You could get away with a slightly larger-than-factory gap, but what would be the point...?
Larry
code5coupe
You could get away with a slightly larger-than-factory gap, but what would be the point...?
Larry
code5coupe
Thanks rocco 16!!
I'll start with . 45 and go from there.
Thank
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
If this is a street car especially, you'll find it to be a complete waste of time. All it accomplishes is shortening your plug life. Been there, done that.
Melting Slicks
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From: Cape Coral FL
Originally Posted by Corvette Kid
If this is a street car especially, you'll find it to be a complete waste of time. All it accomplishes is shortening your plug life. Been there, done that.
Team Owner
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
One must always check the GAP on plugs and set accordingly(As stated above by THEE best forum and it's members!) Never put them in w/out checking! Enjoy!
Thanks,Matt
Thanks,Matt
Le Mans Master
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From: seattle WA
with the Kid.From what I've read there's very little benefit and it comes at an RPM range where most of us don't go. One other thing, I heard awhile back ACDelco was going to market cut backs...wonder whatever became of that.
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
If there was any real-life benefit from cutting back the ground electrode, all spark plugs would be made that way.
(Manufacturers of spark plugs aren't as stupid as we think they are.)
Larry
code5coupe
(Manufacturers of spark plugs aren't as stupid as we think they are.)
Larry
code5coupe
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From: Clarksville Tennessee
The result of installing cut back plugs were not good. It caused my car to miss. My car isn't stock. And I'm running 114 octane fuel. Any suggestion? I'm waiting until the car cools down before I take the plugs out.
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
I suggest you buy a new set of plugs, take them out of the boxes, make sure they are properly gapped, and install them.....MAKING SURE YOU HAVE THE RIGHT PLUG WIRES ON THE RIGHT CYLINDERS!!! 
Larry
code5coupe
Larry
code5coupe
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From: Clarksville Tennessee
Originally Posted by 89Corvette6spdFX3
You need a hotter spark. Did you upgrade the rest of the ignition system?
Safety Car
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From: Lahaina Hi
I think you must have something going on inside your distributor.
In your car why are you running the blue goo C114?
If you aren't above 11 to 1 compression just run regular fuel.
At most I would be running 106 the red.
Cut back plugs are for high compression engines putting out atleast 500 hp.
I run cut backs in my 86 but it jumps off the ground when it is Idleing.
Its around 700hp and I run C116 and C114,15 to 1 compression.
Cut backs just make it easier to fire the fuel which has a higher burn point.
Higher octain takes more heat to fire the cylinder than regular fuel.
In your car why are you running the blue goo C114?
If you aren't above 11 to 1 compression just run regular fuel.
At most I would be running 106 the red.
Cut back plugs are for high compression engines putting out atleast 500 hp.
I run cut backs in my 86 but it jumps off the ground when it is Idleing.
Its around 700hp and I run C116 and C114,15 to 1 compression.
Cut backs just make it easier to fire the fuel which has a higher burn point.
Higher octain takes more heat to fire the cylinder than regular fuel.
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From: Clarksville Tennessee
I don't run 114 daily. Just when I go to the track.( once a week 2 gals 93 octane 3gals. 114). I'll start up grading my distributor piece by piece and leave the cut back guess not
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
What are your guy's opinions on indexed plugs (also for unshrouding the spark?)
At what point, does the "every little bit helps" come into play? Or are you guys saying there's zero gain?
They wouldn't all make em that way because they won't last nearly as long. But then again, looks like someone here bought em that way.
At what point, does the "every little bit helps" come into play? Or are you guys saying there's zero gain?
Originally Posted by rocco16
If there was any real-life benefit from cutting back the ground electrode, all spark plugs would be made that way.
(Manufacturers of spark plugs aren't as stupid as we think they are.)
Larry
code5coupe
(Manufacturers of spark plugs aren't as stupid as we think they are.)
Larry
code5coupe
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From: WI
I have been doing indexing on my cars for a long time. I at first used special washers, now I can generally tell where the threads starts to wear the ground strap will turn out good. For giggles, I indexed the two plugs on my riding mower, the engine ran stronger. I've never noticed a difference on the cars before because the gain is slight but with the small engine having so much less HP I could tell the difference.
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by CentralCoaster
someone here bought em that way.
Just like I've seen U-groove, split electrodes, multiple electrodes, halo plugs, and JCWhitney FireIgnitors from 40 years ago.
They are all gimmicks that have no actual value.
A spark plugs function, and therefor the spark plug itself, is so damn simple that the manufacturer HAS to do something to set their product apart from every other nearly-identical spark plug on the market.
Indexing? It may help, although I have my doubts.
Indexing is supposed to expose the spark to the incoming charge/intake valve.
Problem is, by the time the spark fires, the intake valve is closed and the intake charge is swirling around in a closed chamber that, in effect, has no valves (since they are all closed), just a compressed charge in a featureless chamber.
Cutting back plugs and indexing plugs will not hurt an engine's power output, but they don't enhance it enough to make it worth the effort, either.
My $.02
Larry
code5coupe
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by rocco16
Cutting back plugs and indexing plugs will not hurt an engine's power output, but they don't enhance it enough to make it worth the effort, either.