Spark Plug change, is it worth it?
Thread Starter
Instructor
Joined: Dec 2005
Posts: 108
Likes: 0
From: Gainesville Florida
Spark Plug change, is it worth it?
I'm hitting 100K on my 92 C4 and it's about time to change the spark plugs. Just curious if anyone has good things to say about a spark plug change, or has any tips because I know the plugs are hard to get to. On every other car I have owned I have never noticed any performance difference and I have always thought a plug change is a waste of time and money.
Race Director
Joined: Sep 2005
Posts: 13,269
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From: Sharpsburg Georgia
GA Events Coordinator
You have 100K on your plugs?
Change them IF you can still get them out of the heads.
I bet they are worn down to nubs.
We see about one car a week in our shop that needs big $ because the owner did not keep the car regularly maintained .
When the gap get very wide it causes the ignition to work harder and can lead to some ignition components failing.
But to answer your question, if they are done when they should be, you will not feel any difference.
Greg N
Change them IF you can still get them out of the heads.
I bet they are worn down to nubs.
We see about one car a week in our shop that needs big $ because the owner did not keep the car regularly maintained .
When the gap get very wide it causes the ignition to work harder and can lead to some ignition components failing.
But to answer your question, if they are done when they should be, you will not feel any difference.
Greg N
Team Owner
Joined: Sep 2003
Posts: 25,295
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From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
Might be a good idea. I use regular old Champion Spark Plugs and I just change them out frequently.
AC Delco has problems with the platnum pucks falling out, NGK are too expensive, and Bosch plugs are the complete suck in a 92 LT-1.....ask me how I know?
AC Delco has problems with the platnum pucks falling out, NGK are too expensive, and Bosch plugs are the complete suck in a 92 LT-1.....ask me how I know?
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Yes, I would say that it is time to change spark plugs. No performance change but might see a change in MPG. LT1 is more difficult than a L98. You have to drop the exhaust on the passenger side to get to the back plug. But, I would do it. 
Team Owner
Joined: Oct 2000
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From: Fort Knox, KY
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Go with the NGK Platinums if you've got an LT1 or LT4. They're nowhere near the price of the irridiums, but if I can afford a set of 8, believe me, so can you. They're an excellent plug.
As others have said, when it comes to scheduled, preventive maintenance, you either pay now or pay later.
As others have said, when it comes to scheduled, preventive maintenance, you either pay now or pay later.
Pro
Joined: Jun 2001
Posts: 721
Likes: 10
From: Irvine CA
On my LT-1 I changed mine at 80k and plugs looked new. Book says 100k so you are due.
The key to the #8 plug is to use a plug socket that has a hex end on it. Then use a wrench to loosen it. (no need to drop the exhaust)
When you put them back in, use a piece of fuel line over the end. This allows for a better reach into crowded areas and prevents you from crossing the threads because if it is not going in right the hose will slip around the plug. (learned the hose trick right here on the forum)
Also, use anti sieze on the plugs and DO NOT over tighten them.
You will need to remove some stuff to get at the plugs. Search the archives.
Oh yes, plenty of beer and band-aids.
The key to the #8 plug is to use a plug socket that has a hex end on it. Then use a wrench to loosen it. (no need to drop the exhaust)
When you put them back in, use a piece of fuel line over the end. This allows for a better reach into crowded areas and prevents you from crossing the threads because if it is not going in right the hose will slip around the plug. (learned the hose trick right here on the forum)
Also, use anti sieze on the plugs and DO NOT over tighten them.
You will need to remove some stuff to get at the plugs. Search the archives.
Oh yes, plenty of beer and band-aids.
Safety Car
Joined: Dec 2004
Posts: 4,088
Likes: 0
From: Poop land
I use $0.69 Autolite plugs on mine. No need for that fancy shiaatt! And I drag/road/auto x race mine and have yet to kill them. I'm getting kinda good at auto x. I hate hitting cones though. Just need some antiseize and some elbow grease. In 1 hour, you should be done changing the plugs if you have contortionist capibilities and the right tools.
Racer
Joined: Nov 2005
Posts: 289
Likes: 0
From: Commerce GA
Originally Posted by VictorRussell'92
Might be a good idea. I use regular old Champion Spark Plugs and I just change them out frequently.
AC Delco has problems with the platnum pucks falling out, NGK are too expensive, and Bosch plugs are the complete suck in a 92 LT-1.....ask me how I know?
AC Delco has problems with the platnum pucks falling out, NGK are too expensive, and Bosch plugs are the complete suck in a 92 LT-1.....ask me how I know?
My car ran like sheeot till I changed the plugs to the recommended AC Delcos Rapid Fires. The owner before had some piece of crap Bosch Plantinum Four bull crap in. I have a 92' as well.
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Le Mans Master
Joined: Mar 2004
Posts: 8,700
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From: Ft. Lauderdale Fl
Originally Posted by kopbet89c4
I use $0.69 Autolite plugs on mine. No need for that fancy shiaatt! And I drag/road/auto x race mine and have yet to kill them. I'm getting kinda good at auto x. I hate hitting cones though. Just need some antiseize and some elbow grease. In 1 hour, you should be done changing the plugs if you have contortionist capibilities and the right tools.
Intermediate
Joined: Jan 2006
Posts: 26
Likes: 0
From: nothern california
I changed plugs, cap, rotor, coil, wires and added a msd at 60k. The motor was pinging under lite load. After the change I noticed a big difference. Smooth idle, better acceleration and no ping. I used ac delco rapid fire plugs. It's just maintenance well worth the effort.
Safety Car
Joined: Dec 2004
Posts: 4,088
Likes: 0
From: Poop land
Originally Posted by elefkow
You must be good. It took me four hours and then a lot of beer.
Drifting
Joined: May 2003
Posts: 1,647
Likes: 28
From: Woodbridge NJ
Originally Posted by blown87
You have 100K on your plugs?
Change them IF you can still get them out of the heads.
I bet they are worn down to nubs.
We see about one car a week in our shop that needs big $ because the owner did not keep the car regularly maintained .
When the gap get very wide it causes the ignition to work harder and can lead to some ignition components failing.
But to answer your question, if they are done when they should be, you will not feel any difference.
Greg N
Change them IF you can still get them out of the heads.
I bet they are worn down to nubs.
We see about one car a week in our shop that needs big $ because the owner did not keep the car regularly maintained .
When the gap get very wide it causes the ignition to work harder and can lead to some ignition components failing.
But to answer your question, if they are done when they should be, you will not feel any difference.
Greg N
Race Director
Joined: Sep 2005
Posts: 13,269
Likes: 0
From: Sharpsburg Georgia
GA Events Coordinator
Originally Posted by Brimis
I agree, with no electrode the gap is wider and more spark is needed which in turn will damage other ignition components.
SAAB's with the ignition cassete are well known for this.
3rd Gear
Joined: Mar 2006
Posts: 3
Likes: 0
From: Downey California
bloody knuckles....
Just changed mine out (Took me ~ 3 Hrs.), had to take out the tire splash shielding on pass side, but I swapped the stock plugs w/Bosch platinum +2's and MSD wires and WOW whatta difference!!!!!
Safety Car
Joined: Nov 2005
Posts: 4,590
Likes: 48
From: W MI
I haven't changed them, but I did take them all out to inspect them(I always do this in a new to me car).
Now I get to gloat that I have smaller hands. There are only a few downsides associated with that, somehow I always end up fixing power windows and changing auto light bulbs!
Good Luck!
GT6
Now I get to gloat that I have smaller hands. There are only a few downsides associated with that, somehow I always end up fixing power windows and changing auto light bulbs!
Good Luck!
GT6