rapidfire plugs have incorrect pre-set gap?
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Instructor
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From: Hockessin DE
rapidfire plugs have incorrect pre-set gap?
i just purchased a set of Delco Rapidfire plugs and noticed they were pre-gapped from the facotry at .045. now, in many publications, as well as on this forum, i have been informed that the correct gap for my engine is .035. so which is right? should i leave the gap as is, or reduce it to factory specs? thanks in advance
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Re: rapidfire plugs have incorrect pre-set gap? (tpivette89)
If you want more power, gap at .050 but be prepared for lower mileage and shorter plug life.
.035 is the opposite and .045 is a nice compromise
Jack
.035 is the opposite and .045 is a nice compromise
Jack
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Re: rapidfire plugs have incorrect pre-set gap? (tpivette89)
THats funny the ones I bought at the beginning of July were pre gapped at .035. When I cut them back I gapped to .040 (split the diference between .035 and .045) not had any problems, fuel econmy is the same (unless my foot is in the motor). I did replace the coil, cap, rotor and wires as well.
Burning Brakes
Joined: May 2002
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From: Collegeville PA
Re: rapidfire plugs have incorrect pre-set gap? (tpivette89)
I tried the rapidfires, and after much debate, I ended up leaving them at .045. I have a stock ignition, and they made the car run and idle rough. I ditched them and put the AC Delco "Cut Plugs" gapped at .035 back in and whalah!!! Judging by all of the different opinions, I'd suggest trying them for a few weeks, then either re-gap to .035 or try the "Cut Plugs". Its a PITA to keep changing them, but believe me the gap does make a difference, and it will be worth it in the end. Keep Tweekin'!!!
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From: Lafayette LA
Re: rapidfire plugs have incorrect pre-set gap? (Triple Black 88)
The new Rapidfires are not pre-gapped The first generation of rapidfires were pregapped. In the last year, those have been slowly replaced with the second generation rapidfires. The 2nd gens are platinum and are not pregapped. You will need to regap them to stock specs.
To find out which ones you have, read the back of the box. If it says not to gap and that they are set from the factory, then they are first generation rapidfires. If it says to regap to OEM specs, then they are second gens. There was a redisign in the tips too.
This change over has been going on for quite some time. However, due to the low sales of high dollar spark plugs, there are plenty of first gen rapidfires still in the parts stores.
To find out which ones you have, read the back of the box. If it says not to gap and that they are set from the factory, then they are first generation rapidfires. If it says to regap to OEM specs, then they are second gens. There was a redisign in the tips too.
This change over has been going on for quite some time. However, due to the low sales of high dollar spark plugs, there are plenty of first gen rapidfires still in the parts stores.
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Burning Brakes
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From: Collegeville PA
Re: rapidfire plugs have incorrect pre-set gap? (ZBRA)
ZBRA, the box I had definitly said to Re-gap to OEM specs, but I didn't because that's what it said on their website's Q & A, plus it seemed to be the majority vote in my post. O well, I am happy with the Cut Plugs. When they wear out, I'll gap and try the rapidfires again.
Thanks for the info! :flag
Thanks for the info! :flag
