Proper spark plug gap?

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MisterB

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1980 350 V8. Standard plugs, cap and rotor.

What should I set them to?

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Frankenchevy

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Stock head, ignition, etc I want to say .035

I’m at .060 with my current setup, but I’m pretty sure I’m remembering that correctly.
 

Chevyguy

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1980 350 V8. Standard plugs, cap and rotor.

What should I set them to?

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Should be listed on the emission sticker that's either on the air cleaner housing, or the top radiator mounting plate. My 87's by the radiator.

Clayton

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hunters628

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I just make sure there is actually a gap on the plug and I call it good. Lol. No noticeable performance difference in properly gapped plugs so what’s the point. That’s how I do it on all my rigs. Learned that trick from a vw engine builder of 40+ years.
 

Frankenchevy

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There’s absolutely a difference in plug gaps. Try running my gap on a turbocharged engine. Compression, flame front, timing, ignition strength...there are a ton of variables. I guess on a 160hp 8:1cr v8 it may be a wider window, but at least you’ll get longer plug life and more complete combustion.
 

PrairieDrifter

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I gap at .045
 

Dan Miller

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Ive had alot of mine come preset at .045 . I use AC - R45TS in my stock 350 2bbl ,, seems to do fine for me
 

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Looking online .045 seems to be the recomended gap for your 1980 HEI motor.

Clayton

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Dysco

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Gap certainly does make a difference. The wrong gap means you aren't burning all the fuel, and/or at the right time, which means you are giving away horsepower, torque, and spending more at the pump. It's a factor in the timing and performance of any engine.
Generally with a stock 350sbc,h and carb, .35 is reccommended. An aftermarket hei and/or injection is often 45.
 

MisterB

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Gap certainly does make a difference. The wrong gap means you aren't burning all the fuel, and/or at the right time, which means you are giving away horsepower, torque, and spending more at the pump. It's a factor in the timing and performance of any engine.
Generally with a stock 350sbc,h and carb, .35 is reccommended. An aftermarket hei and/or injection is often 45.
I would agree. If an engine doesn't care about the spark plug gap, it must be running really poorly in other areas.

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78C10BigTen

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I have pre gapped E3 in my tired ol dog so idk.... lol
 

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.045 on HEI
X3
 

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