Autolite 103 spark plug gap (Page 1/1)
cam-a-lot OCT 07, 06:03 AM
Hello

What is the consensus on correct spark plug gap for Autolite 103 on a 3800 SC motor?

My new set seems to be gapped to around .035" but I believe it should be larger

thanks
olejoedad OCT 07, 08:39 AM
It depends on your boost level.

The higher the boost, the smaller the gap.

Start with what the gap is now, if you experience 'misses' at full boost (high rpm), pull the plugs out and drop the gap down.
Repeat until the 'missing' (spark blowout) disappears.
cartercarbaficionado OCT 08, 03:58 AM

quote
Originally posted by cam-a-lot:

Hello

What is the consensus on correct spark plug gap for Autolite 103 on a 3800 SC motor?

My new set seems to be gapped to around .035" but I believe it should be larger

thanks


if it's a built engine idk. if it's a stock motor gap it to a 2001 grand prix gtp SC motor since that is usually the widest spec with the most boost. always gapped mine to .040 running the overdrive pulley on one.
Dennis LaGrua OCT 08, 09:31 AM
I believe the stock spark plug gap setting for the 3800SC is .055". I have my 3800 set ot .050" intercooled, a 3.4" pulley on a GenV with some other small mods. Don't have any misses all the way to the redline.

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