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[C2] C2 Sparkplugs

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Old Aug 22, 2025 | 05:27 PM
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Default C2 Sparkplugs

Are NGK XR4’s still the plug of choice for a 300 hp 327 daily driver?
Thanks much,
D
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Old Aug 23, 2025 | 10:33 AM
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If they match AC R45S you're good in my unprofessional opinion. Dennis
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Old Aug 24, 2025 | 11:40 AM
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Original plug was AC44 but for daily driving 45 is better and cross references to modern NGK XR4
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Old Aug 24, 2025 | 09:34 PM
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The problem is installing the plugs on the passenger's side. Now it's the big issue !
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Old Aug 24, 2025 | 11:11 PM
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Originally Posted by ICON64
The problem is installing the plugs on the passenger's side. Now it's the big issue !
Get at them from the bottom. Take the ignition shields off, then bandage your cut fingers. Jack the front of the car up. All 4 plugs can be reached with a box end wrench and spun out by hand.
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Old Aug 25, 2025 | 09:22 AM
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Originally Posted by ICON64
The problem is installing the plugs on the passenger's side. Now it's the big issue !
Just last week put 45's in the '66 BB, drivers side 8 minutes pass side 45 minutes, that factory A6 compressor keep getting in the way.
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Old Aug 25, 2025 | 09:45 AM
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Change #2 and #4 on an A/C car through the wheel well. Jack up the car, remove the wheel and you can access those two through the dust shield in the wheel well. Use a 3/8" socket with a two inch extension and a swivel. Really not that difficult, at all. I access #6 and #8 from underneath the car...again pretty easy.
And, I like Denso 14U spark plugs.
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