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ACDelco 41-993 Professional Iridium Spark Plug (Pack of 8)
- Iridium offers better engine idle stability and smoother performance
- Iridium allows for smaller, more efficient electrode designs for improved cold starting and quicker acceleration
- Iridium fine-wire electrode helps improve ignition of the fuel and burns away carbon deposits on the tip of the plug as they form, to help improve fuel economy
- One piece suppressor seal blocks radio frequencies that can affect vehicle electronics
- Suppressor seal meters spark energy for longer electrode life and seals against combustion leakage
Adam Escorial
Truck runs good with them in
Truck runs good with them in. I through the boxes out before filling out the rebate and you are to send the bar codes off the boxes in with the rebate form. Sent it in expecting it to be denied but AcDelco sent me it anyway. Two thumbs up to them for that.
Kevin Bailey
Always check your spark plug gaps an adjust them as necessary before installing!
Came on time and packing was good, no visible damage to box holding plugs and or to the individual boxes that held each plug. While changing out my old plugs for these new ones. I did notice that the gaps did not look right so I checked all the new ones and found that not one of these plugs were set at sixtie thousand of an inche as some claim. Always check the plugs gap before installation of your plugs. Most plugs can be adjusted to there recommended gaps, no need to return them if gap is not right for your motor. Other wise you should not be undertaking this adventure in the first place. Adjusting spark plugs is actually easier then installing them. These plugs are no different them most spark plugs and can be adjusted with no trouble at all. 😎
Nathanial Lovgren
Great Plugs!
These, combined with the ACDelco plug wires, will add a tune up to any accomodating model vehicle. I've always used ACDelco replacement parts in my GM vehicles and have never experienced an issue. Sure, plugs are always a PIA to install but they can really make a difference.
Ggja Tabo Tabo
Buyer beware if you need these plugs gapped to .060........
The new production of these plugs seems to come with a higher raised center electrode, safely for only allowing a maximum gap of .050. Unfortunately my old 98 350 calls for a .060 gap. Went to the local parts store, where the guy had some of the same plugs from 2015 on the shelf. Sure enough, the electrode was not as high or raised. I can used these plugs in the Blazer, which allows for a .040 gap, which I know will work well since they are AC Delco. And yes, I have safely gapped these plugs for years.
Ambrosio Rivera
Spark Plugs At A Great Price
I bought these spark plugs for my father's van to replace the ones he had installed. Not only are these spark plugs great quality, but their price on Amazon is very good. When I bought these, there was a mail in rebate available, which made the price of each spark plug even better. So be on the lookout for that. But definitely buy AC Delco parts because they really are top quality and my father has not experienced any problems with his van ever since he replaced a number of parts with this brand.
Brenz Siringan Fenomeno
OEM Sparkplugs - 1998 Chevy Silverado PU w/350cid
Well they're OEM AC-Delco so you really can't go wrong. I've tried third party after market sparkplugs and just really don't like them. I think my truck runs better with OEM parts. My old set had about 80K miles on them and were showing signs of wearing down. Performance is better and no more hesitation at stop lights. Perfect fit, no problems. Installed in a 1998 Chevy Silverado Pickup with a 350. Best engine Chevy ever made IMO.
Ishaz Fwie
... read that Vortec engines (not the LS engines) run better with these plugs
replaced these plugs based on something i read that Vortec engines (not the LS engines) run better with these plugs, and although the gap is wider, my van runs so much smoother and it seems like it has more power. DO NOT attempt to adjust the gap it is factory pre set and acdelco recommends not to adjust the gap, damage will occur to the tip of the plug.
Renn Belladonna
OEM plugs for Vortec 5.7 Liter
OEM replacement part for Vortec 5.7 engines. Plus others I'm sure. But for me specifically 1997 Silverado, 5.7 engine. Please don't gap these plugs. They are set from the factory and not meant to be tampered with. The very tiny Iridium electrode is fragile and should be left alone. If the boxes are beat up, and the gaps look closed up , send them back for exchange. Otherwise, just apply some anti-seize and install as is. OEM plugs are always the best choice.
Emily Gualberto Kempis
good for 50k
the only plug that will run perfectly in my 2000 blazer.the originals lasted 100k before i changed them due to rough idle and sluggish performance.pulled them out and replaced again after 50k.Wow what a difference! I truly think they are great performers up to 50k,after that i feel they remain sluggish but will last.
Trisha Redlund
Pregapped and ready to go!
ACDelco 41-993 Professional Iridium Spark Plug (Pack of 8)
Features:
Adam Escorial
Truck runs good with them in
Truck runs good with them in. I through the boxes out before filling out the rebate and you are to send the bar codes off the boxes in with the rebate form. Sent it in expecting it to be denied but AcDelco sent me it anyway. Two thumbs up to them for that.
Kevin Bailey
Always check your spark plug gaps an adjust them as necessary before installing!
Came on time and packing was good, no visible damage to box holding plugs and or to the individual boxes that held each plug. While changing out my old plugs for these new ones. I did notice that the gaps did not look right so I checked all the new ones and found that not one of these plugs were set at sixtie thousand of an inche as some claim. Always check the plugs gap before installation of your plugs. Most plugs can be adjusted to there recommended gaps, no need to return them if gap is not right for your motor. Other wise you should not be undertaking this adventure in the first place. Adjusting spark plugs is actually easier then installing them. These plugs are no different them most spark plugs and can be adjusted with no trouble at all. 😎
Nathanial Lovgren
Great Plugs!
These, combined with the ACDelco plug wires, will add a tune up to any accomodating model vehicle. I've always used ACDelco replacement parts in my GM vehicles and have never experienced an issue. Sure, plugs are always a PIA to install but they can really make a difference.
Ggja Tabo Tabo
Buyer beware if you need these plugs gapped to .060........
The new production of these plugs seems to come with a higher raised center electrode, safely for only allowing a maximum gap of .050. Unfortunately my old 98 350 calls for a .060 gap. Went to the local parts store, where the guy had some of the same plugs from 2015 on the shelf. Sure enough, the electrode was not as high or raised. I can used these plugs in the Blazer, which allows for a .040 gap, which I know will work well since they are AC Delco. And yes, I have safely gapped these plugs for years.
Ambrosio Rivera
Spark Plugs At A Great Price
I bought these spark plugs for my father's van to replace the ones he had installed. Not only are these spark plugs great quality, but their price on Amazon is very good. When I bought these, there was a mail in rebate available, which made the price of each spark plug even better. So be on the lookout for that. But definitely buy AC Delco parts because they really are top quality and my father has not experienced any problems with his van ever since he replaced a number of parts with this brand.
Brenz Siringan Fenomeno
OEM Sparkplugs - 1998 Chevy Silverado PU w/350cid
Well they're OEM AC-Delco so you really can't go wrong. I've tried third party after market sparkplugs and just really don't like them. I think my truck runs better with OEM parts. My old set had about 80K miles on them and were showing signs of wearing down. Performance is better and no more hesitation at stop lights. Perfect fit, no problems. Installed in a 1998 Chevy Silverado Pickup with a 350. Best engine Chevy ever made IMO.
Ishaz Fwie
... read that Vortec engines (not the LS engines) run better with these plugs
replaced these plugs based on something i read that Vortec engines (not the LS engines) run better with these plugs, and although the gap is wider, my van runs so much smoother and it seems like it has more power. DO NOT attempt to adjust the gap it is factory pre set and acdelco recommends not to adjust the gap, damage will occur to the tip of the plug.
Renn Belladonna
OEM plugs for Vortec 5.7 Liter
OEM replacement part for Vortec 5.7 engines. Plus others I'm sure. But for me specifically 1997 Silverado, 5.7 engine. Please don't gap these plugs. They are set from the factory and not meant to be tampered with. The very tiny Iridium electrode is fragile and should be left alone. If the boxes are beat up, and the gaps look closed up , send them back for exchange. Otherwise, just apply some anti-seize and install as is. OEM plugs are always the best choice.
Emily Gualberto Kempis
good for 50k
the only plug that will run perfectly in my 2000 blazer.the originals lasted 100k before i changed them due to rough idle and sluggish performance.pulled them out and replaced again after 50k.Wow what a difference! I truly think they are great performers up to 50k,after that i feel they remain sluggish but will last.
Trisha Redlund
Pregapped and ready to go!
I bought this for my 1998 Chevy blazer that I had just purchased from my dad because it wasn’t starting and bam. Immediately after install, it started right up! It is pregapped so there’s not much work you have to do to use them. It comes with anti sieze so it will come out easily when it’s time to change them. Great buy, do recommend
I bought this for my 1998 Chevy blazer that I had just purchased from my dad because it wasn’t starting and bam. Immediately after install, it started right up! It is pregapped so there’s not much work you have to do to use them. It comes with anti sieze so it will come out easily when it’s time to change them. Great buy, do recommend