plug gap?
Thread Starter
Member
Joined: Mar 2000
Posts: 172
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From: Marion, IA USA
Car: 91 Camaro Z28
Engine: LS1
Transmission: TKO 600
Axle/Gears: 10 bolt 3.23
plug gap?
What would be a good place to gap plugs at? I noticed that when reading the MSD manual they suggested a rather large gap. I can't remember exactly for for my compression ratio they suggested somewhere around .050 i think. Any problems with going to this when you're putting an MSD6A on? Thanks!
Wally
Wally
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Joined: Oct 1999
Posts: 735
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From: Portales, NM USA
Car: 86 T/A
Engine: 5.0 TPI
Transmission: 700R4
.45 to .50 would be beneficial in a performance coil situation. Increased gap with higher spark will burn the gases more completely..... less emissions, better efficiency, and more power.
Wally (Glen?),
As long as the ignition coil will support the gap, and teh primary ignition components will support the higher primary current of the coil, go as large as you wish.
Remember that higher cylinder pressures require more spark energy to ionize the same gap, so even if your static compression ratios are moderate your effective cylinder pressure can be fairly high with a well-designed cam profile and induction system. If you want to try 0.050", go ahead. If you have trouble with misfiring at higher RPMs and loads, you'll need to reduce the gap or increase the voltage. The MSD box can probably support the coil current required, but a stock coil might not have a large enough effective turns ratio to produce the necessary voltage. A good compliment to the MSD CD box is a high-energy coil.
------------------
Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader
As long as the ignition coil will support the gap, and teh primary ignition components will support the higher primary current of the coil, go as large as you wish.
Remember that higher cylinder pressures require more spark energy to ionize the same gap, so even if your static compression ratios are moderate your effective cylinder pressure can be fairly high with a well-designed cam profile and induction system. If you want to try 0.050", go ahead. If you have trouble with misfiring at higher RPMs and loads, you'll need to reduce the gap or increase the voltage. The MSD box can probably support the coil current required, but a stock coil might not have a large enough effective turns ratio to produce the necessary voltage. A good compliment to the MSD CD box is a high-energy coil.
------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader
<font face="Verdana, Arial" size="2">Originally posted by MikeInAZ:
.45 to .50 would be beneficial in a performance coil situation. Increased gap with higher spark will burn the gases more completely..... less emissions, better efficiency, and more power.</font>
.45 to .50 would be beneficial in a performance coil situation. Increased gap with higher spark will burn the gases more completely..... less emissions, better efficiency, and more power.</font>

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89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else
Thread Starter
Member
Joined: Mar 2000
Posts: 172
Likes: 0
From: Marion, IA USA
Car: 91 Camaro Z28
Engine: LS1
Transmission: TKO 600
Axle/Gears: 10 bolt 3.23
Sorry Vader. My name's Justin, but all my friends call me Wally. So it kinda stuck with me. Thanks for all the great responses.
Wally
Wally
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