What are cut back style sparkplugs
Thread Starter
Race Director
Joined: Jul 2004
Posts: 16,795
Likes: 62
From: Lake Havasu City, AZ
What are cut back style sparkplugs
I've read in a number of places that cut back style sparkplugs will improve performance.
Exactly what are they?
Does one make them by cutting back the electrode or does one buy them?
If former how do I cut them, If latter, can Ihave a recommendation on a brand and source for my 88
thanks
Exactly what are they?
Does one make them by cutting back the electrode or does one buy them?
If former how do I cut them, If latter, can Ihave a recommendation on a brand and source for my 88
thanks
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
They are plugs that have the ground (side) electrode trimmed back so that the end lines up with the SIDE of the center electrode. The theory is that it "unshrouds" the spark.
If you draw a picture of both styles and place a spark in the appropriate place in each drawing, you'll see that it does nothing.
Save your efforts...if this was a valid power-maker, EVERY plug maker would make their plugs this way.
If you insist on spending time and money on gimmicks, buy a Tornado...at least you get a decal.
Larry
code5coupe
If you draw a picture of both styles and place a spark in the appropriate place in each drawing, you'll see that it does nothing.
Save your efforts...if this was a valid power-maker, EVERY plug maker would make their plugs this way.
If you insist on spending time and money on gimmicks, buy a Tornado...at least you get a decal.
Larry
code5coupe
Last edited by rocco16; Jul 22, 2004 at 01:11 PM. Reason: toning down
Team Owner
Joined: Jul 2003
Posts: 24,650
Likes: 8
I just changed my plugs this morning, I cut them back, per 65Z01's instructions.
I used my cut-off rotary tool to trim a little bit off the end of the electrode on the stock style plugs. Dont use rapid fires!
They are stock AC-Delcos, and it does seem to work, the car starts faster now.
I used my cut-off rotary tool to trim a little bit off the end of the electrode on the stock style plugs. Dont use rapid fires!
They are stock AC-Delcos, and it does seem to work, the car starts faster now.
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Here's a quote from 65Z01's page about the effects of the cut back plugs:
"Test Results
After running cut-back Split Fire spark plugs for some time at the strip, I installed some unmodified Rapid Fire spark plugs at the same gap setting and subsequent trap speed was down by 1mph. The following weekend, with the old cut-back spark plugs back in trap speeds were up by 1mph, to their former level. This 1mph increase in trap speed is equivalent to a gain of about 10 HP".
You decide if it's worth it.
"Test Results
After running cut-back Split Fire spark plugs for some time at the strip, I installed some unmodified Rapid Fire spark plugs at the same gap setting and subsequent trap speed was down by 1mph. The following weekend, with the old cut-back spark plugs back in trap speeds were up by 1mph, to their former level. This 1mph increase in trap speed is equivalent to a gain of about 10 HP".
You decide if it's worth it.
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Originally Posted by rocco16
They are plugs that have the ground (side) electrode trimmed back so that the end lines up with the SIDE of the center electrode. The theory is that it "unshrouds" the spark.
If you draw a picture of both styles and place a spark in the appropriate place in each drawing, you'll see that it does nothing.
Save your efforts...if this was a valid power-maker, EVERY plug maker would make their plugs this way.
If you insist on spending time and money on gimmicks, buy a Tornado...at least you get a decal.
If you draw a picture of both styles and place a spark in the appropriate place in each drawing, you'll see that it does nothing.
Save your efforts...if this was a valid power-maker, EVERY plug maker would make their plugs this way.
If you insist on spending time and money on gimmicks, buy a Tornado...at least you get a decal.
Racers have been cutting plugs for decades- the reason large manufacturers don't do it is because it decreases the life of the plug and the gap can change more quickly with wear. If you look at the splitfire (bosch 4+ or whatever), you'll notice that they DO trim back the electrode, but insert 2 or three more to extend the life of the plug. I think it's worth it, if only for peace of mind.
Racer
Joined: Dec 2001
Posts: 392
Likes: 0
From: Gallatin TN
Originally Posted by Ramanstud
Racers have been cutting plugs for decades- the reason large manufacturers don't do it is because it decreases the life of the plug and the gap can change more quickly with wear. If you look at the splitfire (bosch 4+ or whatever), you'll notice that they DO trim back the electrode, but insert 2 or three more to extend the life of the plug. I think it's worth it, if only for peace of mind.
This makes perfect sense to me. Not that the others don't, yes better spark, yes more wear. Less wear with 4 electrodes.
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