Which Rapid Fire plugs for my engine?
Thread Starter
Safety Car
Joined: Jan 2003
Posts: 3,959
Likes: 2
From: Obscurity's Armpit
Which Rapid Fire plugs for my engine?
I did a search on "Rapid Fire" pliugs and found that most Forum users experienced a slight increase in power, smoothness or better emissions.
Since I could use all three, I'd like to know which Rapid Fire would be the best for my ZZ3 with aluminum Twisted Wedge heads (daily driver).
Thanks!
Since I could use all three, I'd like to know which Rapid Fire would be the best for my ZZ3 with aluminum Twisted Wedge heads (daily driver).
Thanks!
Burning Brakes
Joined: Apr 2000
Posts: 1,012
Likes: 0
From: Minnesota
I installed a set of Rapids Fire #7's in my 70 350 on Sunday and there was a noticeable difference in the start and the smoothness of the idle. How much was just a new set of plugs and how much was the Rapid Fires--who really knows--but it made me feel better and thats what counts 
SEMPER FI--1970 Dave
Would like to get a "free shot" at the genius who came up with the layout of ignition shielding
SEMPER FI--1970 Dave
Would like to get a "free shot" at the genius who came up with the layout of ignition shielding
Drifting
Joined: Apr 2003
Posts: 1,323
Likes: 2
From: Castle Hills Texas
The Rapid Fires will run you about $4.50-$5.00 per plug. The rule of thumb is that the higher compression motors generally will require a colder plug. Here is great article explaining heat ranges and the like.
http://www.ngksparkplugs.com/techinf...000&country=US
http://www.ngksparkplugs.com/techinf...000&country=US
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Brett Foote
Safety Car
Joined: Jun 2004
Posts: 4,652
Likes: 80
From: Lakeland Florida
Rapid Fire Plug cross reference
Hello,
I looked up the Rapid Fire numbers on the following website:
http://www.gmpartsdepot.com/sparkplug_chart.html
The numbers cross reference AC Delco spark plug numbers. For the Rapid Fire number 10, it is compatible with the following AC Delco spark plug numbers.
Rapid Fire 10 = R44T, R44TX, R45T, R45TX, R43T,
MR43T,MR44T, R43T6, R46T6
I looked up the Rapid Fire numbers on the following website:
http://www.gmpartsdepot.com/sparkplug_chart.html
The numbers cross reference AC Delco spark plug numbers. For the Rapid Fire number 10, it is compatible with the following AC Delco spark plug numbers.
Rapid Fire 10 = R44T, R44TX, R45T, R45TX, R43T,
MR43T,MR44T, R43T6, R46T6
Drifting
Joined: Apr 2003
Posts: 1,323
Likes: 2
From: Castle Hills Texas
I would assume that the number represents the heat range of the plug. I don't know for sure which way is which though. You would assume that a 10 is hotter than a 2...but maybe it is the other way around.
