AC Delco Rapidfire Gap???
Thread Starter
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
AC Delco Rapidfire Gap???
I just got a set of AC Delco Rapidfires, and the guy at the speedshop told me that they are pre-gapped. I just checked them and they are all .045. Stock calls for .035.
What should I do... :confused:
What should I do... :confused:
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
Re: AC Delco Rapidfire Gap??? (Triple Black 88)
I left my Rapidfires alone and went with the pre-gap. I did cut them back today because I was bored, but that shouldnt affect the gap.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: AC Delco Rapidfire Gap??? (VetteNoob)
I did cut them back today because I was bored, but that shouldnt affect the gap.
I run AC Delco Rapidfire #5 and I regap them to 0.035".
Le Mans Master
Joined: Jan 2002
Posts: 5,320
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From: Kyle TX (Because Mojo Made me fill it in)
Re: AC Delco Rapidfire Gap??? (scorp508)
Hmm...so you think the cutting back would have changed my gapping? All I did was take a dremel and cutting disk and sanded it down.
Thread Starter
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
Re: AC Delco Rapidfire Gap??? (scorp508)
Scorp, you re-gapped them after cutting them back, or out of the box? The electrode just barely crosses the center electrode which is very thin. I don't think you could have cut more than 1/16. Do I have this straight?
Cut Rapidfires #5 = .035
Not Cut Rapidfires = .045 (Pre-gapped)
Which is better, and what are the effects of wrong gap :confused:
Cut Rapidfires #5 = .035
Not Cut Rapidfires = .045 (Pre-gapped)
Which is better, and what are the effects of wrong gap :confused:
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Hmm...so you think the cutting back would have changed my gapping? All I did was take a dremel and cutting disk and sanded it down.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Scorp, you re-gapped them after cutting them back, or out of the box? The electrode just barely crosses the center electrode which is very thin. I don't think you could have cut more than 1/16. Do I have this straight?
The wrong gap "could" lead to slightly worse gas mileage, incomplete combustion, and if the ignition system is weak misfires.
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
Re: (scorp508)
At least R&Ring the plugs is nothing like a water pump. :D I guess I should at least check them since I will be driving a good 200 miles tomorrow. hehe
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Thread Starter
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
Re: (scorp508)
OK, I did a search, and got this from the AC Delco Rapidfire web site under FAQ.
I purchased a set of ACDelco RAPIDFIRE spark plugs that do not match my vehicle's gapping requirements. Can I change the gap on ACDelco RAPIDFIRE plugs?
Per package directions, ACDelco does not recommend changing the gap because the RAPIDFIRE plug comes pre-gapped.
RAPIDFIRE spark plugs are pre-gapped. What about your other "regular" spark plugs, say, for a 1989 Lincoln Mark VII?
In regards to spark plug gapping, please always check the instructions on the packaging, and also check the gap before placing the plugs in your engine. Most "regular" spark plugs do not come "pre-gapped".
I guess I'll leave them at .045 :confused:
I purchased a set of ACDelco RAPIDFIRE spark plugs that do not match my vehicle's gapping requirements. Can I change the gap on ACDelco RAPIDFIRE plugs?
Per package directions, ACDelco does not recommend changing the gap because the RAPIDFIRE plug comes pre-gapped.
RAPIDFIRE spark plugs are pre-gapped. What about your other "regular" spark plugs, say, for a 1989 Lincoln Mark VII?
In regards to spark plug gapping, please always check the instructions on the packaging, and also check the gap before placing the plugs in your engine. Most "regular" spark plugs do not come "pre-gapped".
I guess I'll leave them at .045 :confused:
Le Mans Master
Joined: Jan 2002
Posts: 5,320
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From: Kyle TX (Because Mojo Made me fill it in)
Re: (Triple Black 88)
Im pretty sure you can gap the Rapidfire #1 plugs. If you cant, oops....I just did. Most of the plugs were still at .045 (cept for 2 at .050). I regapped them all to .035 as per Scorps recommendation. I guess I will see what happens tomorrow when I drive.
Drifting
Joined: Aug 2001
Posts: 1,550
Likes: 27
From: Minneapolis MN
Re: AC Delco Rapidfire Gap??? (CG77VETTE)
I just installed Rapidfire #1's in my '86 iron head and gapped them out of the box at .035 which is what the factory specs call for.
Team Owner
Joined: Mar 2000
Posts: 83,383
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From: Boston, MA
Per package directions, ACDelco does not recommend changing the gap because the RAPIDFIRE plug comes pre-gapped.
Safety Car
Joined: Dec 2000
Posts: 3,767
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From: Jacksonville Fl
Re: AC Delco Rapidfire Gap??? (Triple Black 88)
I put my Rapid Fires at .050"
A larger gap helps low RPM efficiency and smoothness. It can make the coil have to work a little harder at high RPM's, but since I am driving a stock L98 ( well, almost ) with the stock ignition, I'm not too worried about high RPM power loss from the ignition system, I think the cam has more of an effect on that. :crazy:
[Modified by BBA, 8:17 AM 7/12/2002]
A larger gap helps low RPM efficiency and smoothness. It can make the coil have to work a little harder at high RPM's, but since I am driving a stock L98 ( well, almost ) with the stock ignition, I'm not too worried about high RPM power loss from the ignition system, I think the cam has more of an effect on that. :crazy:
[Modified by BBA, 8:17 AM 7/12/2002]
Safety Car
Joined: Feb 2000
Posts: 4,230
Likes: 0
From: VA
Cruise-In II Veteran
Re: AC Delco Rapidfire Gap??? (BBA)
Ran mine at .45, it ran great. I always verify the gap. Never know if it changed during shipping from factory.
[Modified by ConeKLR, 9:26 AM 7/12/2002]
[Modified by ConeKLR, 9:26 AM 7/12/2002]
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: AC Delco Rapidfire Gap??? (Triple Black 88)
I think if your ignition is in good shape, go with the larger gap. It does the same as cutting the plugs back. You just exposing more of the spark.
If you see a considerable amount of difference between the .035 gap and the .045 gap. I would seriously start looking at ignition components. Something is not right.
If you see a considerable amount of difference between the .035 gap and the .045 gap. I would seriously start looking at ignition components. Something is not right.
Le Mans Master
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Re: AC Delco Rapidfire Gap??? (Triple Black 88)
I just got a set of AC Delco Rapidfires, and the guy at the speedshop told me that they are pre-gapped. I just checked them and they are all .045. Stock calls for .035.
What should I do... :confused:
What should I do... :confused:
Thread Starter
Burning Brakes
Joined: May 2002
Posts: 986
Likes: 99
From: Collegeville PA
Re: AC Delco Rapidfire Gap??? (Triple Black 88)
Well I installed the Rapidfires tonight. I ended up leaving them gapped at .045. This thread has shown everything from .035 to .050 and everything in between. Doesn't sound like anyones had problems, so .45 should be OK. Thanks for the help.
Steve :flag
Steve :flag