ACDelco Rapid Fire Performance Plugs
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Joined: Jul 2004
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ACDelco Rapid Fire Performance Plugs
I see AC Delco Rapid Fire plugs advertised as having better gas mileage and 27 percent smoother idle for C5s. Anyone use these and what do you think about them compared to OEM plugs?
Team Owner
Joined: May 2001
Posts: 87,375
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From: Western NY
I had a set in my Z-28 for 3-4 years. They ran just fine, but I didn't notice any serious gains, either in performance or gas mileage. I replaced them last winter, while the car was in hibernation, and put a set of Bosch platinum +4s. They work just fine also, but again the SOTP dyno saw no difference.
Based on my experience over the years, at least on the street, the plugs don't really offer any gains, unless you have one that is just plain fouled out due to a problem in the ignition or fuel system.
Based on my experience over the years, at least on the street, the plugs don't really offer any gains, unless you have one that is just plain fouled out due to a problem in the ignition or fuel system.
Drifting
Joined: Feb 2003
Posts: 1,761
Likes: 235
From: North Carolina
Originally Posted by PVHolgado
Didn't the AC's have a "puck" issue- the little nib breaking off or something-
I use NGK 55's and have no issues - Haven't had any long term experience yet though-
I use NGK 55's and have no issues - Haven't had any long term experience yet though-
The original Delco's part # 41-931 had that problem, not sure of the model years they were installed, would assume at least 1997 and 1998, the Iridium 41-985's replaced those.
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
Originally Posted by MAC5
The original Delco's part # 41-931 had that problem, not sure of the model years they were installed, would assume at least 1997 and 1998, the Iridium 41-985's replaced those.
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
Originally Posted by TheRadioFlyer
haven't tried them in a C5 but when i used them in my silverado along with a complete MSD kit i noticed about a 1-2mpg gain on the highway
If I were to hazzard a guess, I'd say the MSD kit got you the biggest gain.
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