Coil + Best Spark Plugs?
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,044
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From: Henrico VA
Coil + Best Spark Plugs?
Anybody know if a Pertronix Flame Thrower II Coil will work with 1969 small block? Also are NGK Spark Plugs better than Bosch? What's that best out there? Lastly, what would be the best plug gap with this combo? Thanks!
Burning Brakes
Joined: Sep 2006
Posts: 967
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An underpaid guy at Oreilly tried talked me into their Bosch Platinums and the car ran worse than before. I went back and bought some ngk plugs suggested by someone I worked with and the difference was unmistakable.
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Not only did they work great they fit under the headers better and were cheaper.
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Not only did they work great they fit under the headers better and were cheaper.
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Tech Contributor
Joined: Jun 2004
Posts: 20,931
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
High likelihood it would work. The question is: Why do you want it? Do you have any technical documentation that this coil is better than the stock coil? Shiny paint and stickers don't make horsepower.
Le Mans Master
Joined: Mar 2004
Posts: 7,503
Likes: 1,511
From: Little Rock AR
Your car will not run better with a Pertronix coil. It might even make it run worse. A Pertronix coil did that to me. I went back to stock because it works. As always - JMO.
-Mark.
Race Director
Joined: Apr 2003
Posts: 19,352
Likes: 654
From: Tampa, Florida
I bought my coil at Autozone. They didnt have any 'stock' coils so I grabbed an Accel from the 'performance' isle.
Plugs are funny. Bosch +4's were the best plug I ever used in the '94. Each application needs a different plug.
Plugs are funny. Bosch +4's were the best plug I ever used in the '94. Each application needs a different plug.
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 739
From: Youngstown Ohio
I ran the Pertronix Flame Thrower II coil with my '69 sm. block for several years. This coil is best suited for the Pertronix Ignitor II ignition (which I also used), as it has less resistance than the regular coil but will work with other ignitions; but adding it alone won't show noticeable difference if your current coil is working good. However, the Pertronix package worked flawlessly for years with excellent performance. (I never had to remove the dist. cap for maintenance ever). I used a .045 plug gap with regular Delco plugs; tried others, but none worked better for me, and the price is friendlier. Also IMO, electronics is light years ahead of points (that's why new cars don't have 'em.)
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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I'm running a stock Bosch replacement coil on my 9 sec. 540. Never misses a beat. If you look real close in the center picture you can see it mounted to stock coil bracket right behind throttle bracket. Lots of hype out there!
Plugs are same way. Use whatever you like. NGK's do very well in extreme situations like N20 etc....but I've run just as fast on basic A/C extended tip street plugs. For example, the extended tip, super hot A/C's I use all the time on the street and quite often at the track are literally over 3 years old. Never touch them. I have a colder set of NGK's I use when I get excited and want to spend some extra time before I go to the track..but mainly it's because they don't have as many miles on them and are easier to *read* to make sure jetting is still in the game.
You don't need whizbang trick stuff on these cars. Newer electronic stuff is a lot pickier about it..but not this stuff.
JIM
Plugs are same way. Use whatever you like. NGK's do very well in extreme situations like N20 etc....but I've run just as fast on basic A/C extended tip street plugs. For example, the extended tip, super hot A/C's I use all the time on the street and quite often at the track are literally over 3 years old. Never touch them. I have a colder set of NGK's I use when I get excited and want to spend some extra time before I go to the track..but mainly it's because they don't have as many miles on them and are easier to *read* to make sure jetting is still in the game.
You don't need whizbang trick stuff on these cars. Newer electronic stuff is a lot pickier about it..but not this stuff.
JIM
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Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
My '69 427/435 has a Flamethrower II installed by the previous owner and it runs fine. I have AC RapidFire plugs and like them as well.
A coil will only put out what voltage is necessary to fire the spark across the plug gap. If it takes 30,000 volts to fire the spark, your 40,000+ volt coil will only put out 30,000 volts. If your engine is kept at peak state of tune, a stock coil is all that's necessary unless you like the chrome coil or the red color of it, or the little sticker they come with you place somewhere to tell the world what parts you're running.
What you should be more concerned about in a coil is its saturation or recovery time...how fast it rebuilds its spark energy after each pulse. That's where a performance coil can beat a stock unit...and then usually at higher rpm's only will it make a difference.
A coil will only put out what voltage is necessary to fire the spark across the plug gap. If it takes 30,000 volts to fire the spark, your 40,000+ volt coil will only put out 30,000 volts. If your engine is kept at peak state of tune, a stock coil is all that's necessary unless you like the chrome coil or the red color of it, or the little sticker they come with you place somewhere to tell the world what parts you're running.
What you should be more concerned about in a coil is its saturation or recovery time...how fast it rebuilds its spark energy after each pulse. That's where a performance coil can beat a stock unit...and then usually at higher rpm's only will it make a difference.
Melting Slicks
Joined: Jul 2004
Posts: 2,577
Likes: 2
From: Long Island New York
I have the Accel Super Coil in my car and stock AC Delco spark plugs, both work flawlessly. My original coil went bad and I got a great deal on the Accel from someone, otherwise I would have replace it with another stock coil.
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,044
Likes: 0
From: Henrico VA
I see what you're saying. I just wanted to put a couple little cheap upgrades on the new engine. Do you think it would be designed to work with the Pertronix electronic ignition better than the stock one?
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
The Pertronix is a very good electronic ignition conversion...probably the standard others are measured against without replacing the entire distributor.
If you make the change, try it with the stock coil. If you're happy with the way it runs, why bother changing the coil? If you decide you want a different coil, it's an easy swap.
To be honest, the electronic ignition conversion will not really make your car run much, if any better compared to a properly tuned points ignition (in a stock engine). Where a points ignition slowly degrades with mileage and time (along with timing changes, etc.), the electronic ignition maintains setting indefinitely, outside of distributor wear, which can occur with any ignition.
If you make the swap, don't expect miracles, but you can expect decreased maintenance, longer spark plug life and the like.
If you make the change, try it with the stock coil. If you're happy with the way it runs, why bother changing the coil? If you decide you want a different coil, it's an easy swap.
To be honest, the electronic ignition conversion will not really make your car run much, if any better compared to a properly tuned points ignition (in a stock engine). Where a points ignition slowly degrades with mileage and time (along with timing changes, etc.), the electronic ignition maintains setting indefinitely, outside of distributor wear, which can occur with any ignition.
If you make the swap, don't expect miracles, but you can expect decreased maintenance, longer spark plug life and the like.
Safety Car
Joined: Oct 2000
Posts: 3,593
Likes: 103
From: Southern Indiana
I always buy a hotter coil like an Accel and then gap my plugs .005 wider so you can take advantage of the hotter spark.
A longer hot spark is better than a short hot spark.
I tested spark plug gaps on a hot street car years ago and you can gap too far open and really loose power, so I kept backing the gap closer until I hit the sweet spot and it really makes a differnce.
Good wires help also, not Autozone pre mades.
A longer hot spark is better than a short hot spark.
I tested spark plug gaps on a hot street car years ago and you can gap too far open and really loose power, so I kept backing the gap closer until I hit the sweet spot and it really makes a differnce.
Good wires help also, not Autozone pre mades.
Tech Contributor
Joined: Jun 2004
Posts: 20,931
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I always buy a hotter coil like an Accel and then gap my plugs .005 wider so you can take advantage of the hotter spark. How do you know that the Accel coil is "hotter"? Unless you've had better luck than I have, I have never been able to obtain actual electrical specs of aftermarket coils, or most aftermarket modules. Buying a coil without comparing the electrical specs is like buying a camshaft in a plain brown wrapper. How do you know what you have without actual specs and numbers?
A longer hot spark is better than a short hot spark. I totally agree. The question is, who's part will actually deliver that.
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A longer hot spark is better than a short hot spark. I totally agree. The question is, who's part will actually deliver that.
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Years ago I bought a parts kit to put a magnetic reluctance pick-up coil in my stock tach-drive distributor. I measured the waveform with an oscilloscope to determine what shape it was. I found out it is similar to an HEI pick-up waveform, so I hooked it up to a remote mounted HEI module (under the shielding). I have a total of about 55 bucks in this conversion. It runs flawlessly, and I haven't had to change plugs or touch the system in years.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 39
From: Fremont CA
Pertronix Ignitor upgrade full 12VDC feed to Pertronix coil and AC Spark Plugs in my Chevy (why put foreign parts in your Chevy?) My Pertronix coil was made in the USA, buddy of mine just bought one, the sticker on the bottom said: Made in China AAAAAAAAAARRGGGGGGGGHHHHH!!!!
