when need new plugs?
Thread Starter
Safety Car
Joined: Sep 2002
Posts: 4,030
Likes: 6
From: Maryland
when need new plugs?
When do plugs really need to be done if I don't want to lose more than 5-10 hp for LS6? I bought this car used several years ago and I assume the plugs are OEM.
Experiences? I've never seen a noticable benefit from a plug change dispite my expectations of smoother running, more responsive, etc.
Thanks
Andy
Experiences? I've never seen a noticable benefit from a plug change dispite my expectations of smoother running, more responsive, etc.
Thanks
Andy
Pro
Joined: Dec 2009
Posts: 719
Likes: 2
From: Columbia South Carolina
Plugs degrade ever so slightly over a period of time. I changed mine at 20,300mi on a 2000 and was surprised to find most with over sized gaps.
after the change the car did run smoother and had a better response and pickup.
Aside from that, depending on your car mileage, you could prevent them from seizing up and being more difficult to change at the 100,000 mile recommendation change.
after the change the car did run smoother and had a better response and pickup.
Aside from that, depending on your car mileage, you could prevent them from seizing up and being more difficult to change at the 100,000 mile recommendation change.
Last edited by Jewjenk; Aug 15, 2011 at 02:00 PM.
Melting Slicks
Joined: May 2001
Posts: 2,456
Likes: 8
From: Cockeysville Maryland
Cruise-In IV Veteran
Daytona Jam 1 Veteran
In my opinion plugs for our cars do not need to be changed but every 15k or so depending upon driving habits and I suggest changing the wires at the same time.
I think you will definitely notice when either of those components starts going bad.
I think you will definitely notice when either of those components starts going bad.
Le Mans Master
Joined: Oct 2008
Posts: 8,887
Likes: 981
From: Whitby Ont.
Put headers on and changed plugs and wires at same time, old plugs only had 70,000 km on them, checked the gap and was 52. amazing it even ran. So I would be changing them at 50,000km from now on.
Thread Starter
Safety Car
Joined: Sep 2002
Posts: 4,030
Likes: 6
From: Maryland
...and about wires specifically...do the wires need to be changed because the plugs are hard to access and wired damage is common in getting the wires off to access the plugs? (had this on an Fbody...always needed new wires on that for every plug change)? Or do you only do wires if they really are old/worn/burned???
Thanks
Andy
Last edited by sothpaw2; Aug 18, 2011 at 12:56 PM.
Drifting
Joined: Jan 2008
Posts: 1,722
Likes: 138
From: Florida
St. Jude Donor '09
These things are not difficult to determine; there is a procedure in the service manual for checking the resistance on the plug wires to determine if they are still good.
As far as the plugs are concerned, a visual inspection for fouling, electrode damage, insulator cracks and a proper gap should determine if they are still fit for service.
As far as the plugs are concerned, a visual inspection for fouling, electrode damage, insulator cracks and a proper gap should determine if they are still fit for service.
Melting Slicks
Joined: May 2001
Posts: 2,456
Likes: 8
From: Cockeysville Maryland
Cruise-In IV Veteran
Daytona Jam 1 Veteran
With 50k mi are the plugs/wires overdue? I think the wires are a little newer, GMPP red. If I'm just concerned about high rpm power (not a smooth idle), do I need to change the plugs/wires now?
...and about wires specifically...do the wires need to be changed because the plugs are hard to access and wired damage is common in getting the wires off to access the plugs? (had this on an Fbody...always needed new wires on that for every plug change)? Or do you only do wires if they really are old/worn/burned???
Thanks
Andy
...and about wires specifically...do the wires need to be changed because the plugs are hard to access and wired damage is common in getting the wires off to access the plugs? (had this on an Fbody...always needed new wires on that for every plug change)? Or do you only do wires if they really are old/worn/burned???
Thanks
Andy
You could pull some of the plugs and see what they have to say and decide then.
I would not say that the wires on our Corvettes are that difficult to access and remove, unlike some of the plugs which are downright hard to get out.
Our cars throw off a lot of heat at the exhaust manifold area, with headers even more and even if they are coated so over time I think there could be some damage to the wires and that's why I change them maybe more than is necessary.
Melting Slicks
Joined: Jan 2007
Posts: 2,170
Likes: 6
From: Oilerville Edmonton
St. Jude Donor '08
I changed the plugs at 55k miles when I did the headers and the gaps were WAY out. they were so large my plug gapper could not measure them. I did headers and a mail order tune along with new wires and plugs so it is hard to say what the effect of the plugs alone was but it had to be positive. its worth pulling a few plugs to see what they look like.
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Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
With today's new material plugs--- platinum irridium etc---They are factory installed for one reason--They just last longer--Some manufacturers say every 100K miles---
Real world ?? IF you don't take them out at least every 50K miles or so---They won't come out !!OR they break off when taking them out--creating yourself some new headaches---As carbon builds up--the carbon sort of "welds" the threads to the head !!!
My opinion is to change them every 30K--BUT not to use them pricey material plugs---adding HP with plugs ?? a myth---If you gain HP with a plug change--chances are they were bad anyway and ANY plug would have made it run better !!!
To me the best plug for an LS engine is the NGK TR5 or TR55--
Gapped at .040----- A plain old copper core plug--Copper is the best core for removing heat--- If you follow NASCAR--Trust me --with everyone running basically the same engine---If they could gain 4 HP with E3 plgs or some other majic plug--they would all be running them !!! But real world they don't---They use copper core NGK-Champion's
Wires IMHO should be changed to something better than stock at the
1st plug change-- 40-50k miles or 5 years
Real world ?? IF you don't take them out at least every 50K miles or so---They won't come out !!OR they break off when taking them out--creating yourself some new headaches---As carbon builds up--the carbon sort of "welds" the threads to the head !!!
My opinion is to change them every 30K--BUT not to use them pricey material plugs---adding HP with plugs ?? a myth---If you gain HP with a plug change--chances are they were bad anyway and ANY plug would have made it run better !!!
To me the best plug for an LS engine is the NGK TR5 or TR55--
Gapped at .040----- A plain old copper core plug--Copper is the best core for removing heat--- If you follow NASCAR--Trust me --with everyone running basically the same engine---If they could gain 4 HP with E3 plgs or some other majic plug--they would all be running them !!! But real world they don't---They use copper core NGK-Champion's
Wires IMHO should be changed to something better than stock at the
1st plug change-- 40-50k miles or 5 years